Why The Ford 9 Inch Is Great And Why You May Not Want To Use One In Your Car. Pinion Height Matters

[@glennnickerson8438]

I remember when you could go into the junkyard and get a 9 inch Ford rear axle for under a hundred bucks and you had choices in gear ratios and widths... Man I'm getting old!🤓

[@Terminxman]

Just the fact that you can pull the carrier out and set it up on a table and not laying on the ground under your vehicle (unless you have a lift, or take the rear end out, etc) is very important to me.

[@TheBrokenLife]

I strongly agree. I pretty much refuse to setup gears under a vehicle.

[@flinch622]

As a 12 bolt owner, I do find dropping the whole rear a tad inconvenient. But so is trying to shim things in place [I don't have the luxury of a lift].

[@rle1020]

Plus you can have different center section to swap for different types of racing.

[@tland3900]

Very interesting vid😎👍

[@BuzzLOLOL]

The much more available used and cheap Ford 8.8" is popular... Is the Ford 9 3/4" used in SUVs stronger than the 9"? Getting into cars from the curb side used to be the LAW! In old 1940's-50's shows, most people, even drivers, get in from the curb side and slide over...

[@bobkonradi1027]

One thing about the Ford 9-inch that sticks with me to this day, it happened 25-30 years ago or more, it was a NASCAR race on TV that I was watching in real time. Bobbie Allison pulled into the pits, and something in the rear broke for some reason, it was a fluke. There was a yellow flag at the time and everybody pulled into the pits for tires and fuel. Something in Allisons 3rd member broke. The crew chief immediately sent one crew member to their transporter to get another 3rd member, and as he was gone, the rest of the crew jacked up the car, took off the tires, pulled out the axles, took off the 3rd member, then the man that was sent to get another 3rd member got back to the pits, they put in a whole new 3rd member, reassembled the axle, Allison got back on the track, and never lost a lap, because everybody was in for gas and tires. He was at the very rear of the same lap, but it was the same lap. If he'd been running anybody else's axle, they would have had to disassemble the center section with a spreader, and everything else involved with a Chevy 12-bolt or a Dana 44 or 60, and he would have been screwed. But because the Ford 3rd member was pre-assembled, it was easy(ier) to deal with. He didn't win the race, but he was in the money and got some points. All because the Ford 3rd member was easy to deal with. Same thing at the drags, somebody is racing, he decides he doesn't have the correct axle ratio for that day's conditions, he wants to change ratios, if he's got a Chevy 12 bolt or Dana, its a couple hour job to change gears. If he's got a Ford 9-inch, he just pulls the axles, unbolts the 3rd member, puts in another one with a different ratio, puts the axles back in, buttons it up and away he goes. Now, lower class racers can't afford several 3rd members to be on hand, but a higher class racer that wants to change rears, he could easily have a couple of 3rd members in his trailer. as needed.

[@M21-w1y]

Yeah, you will see all real race cars use the Ford design third member just for that reason. The ease of setting up many different ratios and having them on hand ready to go. How fast and easy it is to change one out and by their design , they are simply stronger. This mopar guy is an idiot, they think that mopar crap is all there is, you can’t teach them anything 😂

[@billschwandt1]

I really learned a lot from these diff videos. Your communication style is direct and informative. I have driven lots of different diffs at all levels of customization and I am confident I can explain them better now than I ever could before thanks to this differential series. Thank you for making them.

[@Portuguese-linguica]

Stylist hate engineers. Engineers hate stylist. Mechanics hate both . It's a beautiful world .

[@mindeloman]

Knew a guy that found a junkyard 9" rear axle out of a Lincoln Mark V that was factory rear disc. I had no idea Ford made 9" axles with rear disc. What a learning moment.

[@c103110a]

Another benefit of the 8.75 and 9.0 inch is the drop out center section. The 12 bolt is a PITA to switch gears.

[@rustybritches6747]

Absolutely, I think thats pretty much what tony was covering in this episode, dropout third members! The Ford 8-inch doesn't get enough love tho they can also be built very strong nowadays!

[@BPattB]

@@rustybritches6747 I'm glad to hear you like the Ford 8in. I currently am running about 340 HP/TQ on my 65. I'm going to rebuild the 8in I have and run 3:55 with track-loc. From my research they are good to 400 if you rebuild with quality parts.

[@misters2837]

@@rustybritches6747 I have put brutal amounts of horsepower and abuse on "Mostly Stock" 8-Inch rears in Mavericks and Similar Vehicles....It does NOT get nearly the love it should and interestingly I have been told that its "Far Weaker" than an 8.8 axle...And maybe for housing strength (weight capacity) but "Raw Torque" No Way! - I have destroyed many more 8.8's than 8" - Granted neither can take the 1000HP abuse that a 9" can take with same ease.

[@mountainsgarage]

Strange Engineering makes a 9” center with 12 bolt pinion placement for Stock and Super Stock for the reasons you mentioned.

[@sethhale8828]

For someone with minor knowledge on rear ends this is a great video

[@raiderjohnthemadbomber8666]

I use the 8.8 in my little street rod. After market gears are no problem and they're bullet proof. Thanks for the tutorial Professor Tony.

[@mastercricket7626]

good to know as i am at a choice point on my build and am trying to sort throu what would be most useful and interchangeable easily but also affordable in case i constantly grenade them 😂 😂

[@qwerty2008100]

I put an 8.8 in my ranger. So far I'm loving it. It'll probably be my go to axle for custom stuff. Right now, they're super cheap, so probably about the best bang for buck option out there.

[@ericwilson2585]

Heck I love this differential stuff, nobody ever talks about, the what, the rear end???? Lol... Thanks for the rearend info Tony, that was really great.

[@EricaMTB]

The Rover differential out of a series Land Rover has the pinion at about 3 o'clock. It's good for almost 50hp.

[@tomcummings655]

A friend of mine with a circle track car[where you are changing ratios back and forth all the time] had the best reason for running the 8 3/4 rear-"nobody borrows my damn gears!!"

[@rockymeyers4030]

Ford 8.8 is the new junkyard jewel now

[@TheBrokenLife]

The 8.8" is an almost exact copy of the Chevy 12 bolt, so... everything old is new again. That said, 8.8 inventory will be drying up in the near future. I don't think Ford has built much except maybe some F150s that use one and I think those are "weird" ones compared to all of the passenger car stuff from days gone by.

[@tomdamon7208]

@@TheBrokenLife A 8.8 has a different pinion position than any Mopar rear . Mopar engines and transmissions are offset 1/2-1" to the passanger side of the car . this puts a compound angle on the driveshaft which shortens its life . IMO opinion anyone using an 8.8 ford is an economic reason . I'm not saying "cheap" here .

[@CanadaBud23]

Many up here in the junkyards. People still pitching 8.8's for big dana's and ford 9's. Good for me, because it's super cheap with LSD, there's like 50 of them in any yard at any given time, parts are everywhere and a slightly built welded one is cheap and can survive 800+HP daily.

[@TheBrokenLife]

@@tomdamon7208 I wasn't speaking specifically to Mopar swaps, but usually the drive line in any car isn't directly on center. You want some amount of lateral misalignment between the front and rear universal joints to help equalize the velocity changes between them. I don't think 1" is all that extreme from what I've observed in the wild. I think Ford F trucks from the 60s and 70s had something crazy like a 4" offset. I'm also not the guy to teach a course on this subject. There's a bunch of trigonometry involved. 😆 That said, no 8.8 built in the last 20 years is going to be a direct bolt in to almost any car and I would expect customization. I absolutely agree that cost is a big factor on why guys go that way. I can buy disc brake 8.8"s pretty much as fast as I can dial the phone for almost scrap price. On a street car with 3 season tires, I doubt you'd ever break either a 8 3/4" or 8.8" without working to do it. That makes it a pretty appealing option.

[@rockymeyers4030]

​@@tomdamon7208 I think some guys have been getting the explorer 8.8, shortening the long side to equal the short side, then getting one more short axle. Then they have a slightly narrowed housing for cheap

[@thomasward4505]

On my latest Street/race car project I used a strange Dana 60 which has been redesigned by strange and its many pounds lighter than the original and just as strong or stronger. I think it was less than 40 lb heavier than the eight and three quarter which I had already broken twice. And it was cheaper than a custom 9 in

[@patford8986]

One thing you didn't mention is tha for other forms of racing, often the optimal gear ratio varies for different tracks. The removable carrier axles make changing the ratios easy. For offroad use where you can have very high torque at low speed the 9 inch is ver good. I love the removable pinion carrier, it makes setting the depth so much easier!

[@jimmy_olds]

I’ve always wanted to know how the factories mass produced setting up the ring and pinions. A relatively precise deal to replicate, while churned out by the millions

[@James-hd4ms]

I think they have some sort of a machine tool.

[@Broken_Yugo]

I'd guess some sort of big precision fixture/machine that allows direct measurements of the relevant parameters, so they can set up the gear mesh directly and take all the skill out of it. I doubt they're going off pattern as anything more than a QC check, if at all.

[@imtheonevanhalen1557]

I worked in a transmission factory back in the '80's......I won't mention the name, but the company came south to escape the unions. Set-up a brand new HUGE factory and filled it with WW2 and 1950's tech machining stations they used up north . Those old machines worked VERY well most of the time.....blew my mind.

[@garypeatling7927]

Still set up with engineers ink to check

[@karensavarese5684]

Great video! I know what your talking about, but, love the way you explained it. Had forgotten about the 57-59 Ford floorpan issues,, right on,,,K

[@joealbert7773]

Interesting fact about right side entry and exit. It started well before the 50's. My 28 Model A has an interior lock on the drivers door and an outside key lock on the passenger door. Back then the idea was to enter and exit from the right side. Also, Ford had the rear support pinion bearing on rear axles from the 30's. The Hallibrand rear in my sprint car had the rear support bearing and it used an old Ford (1940's) ring and pinion.

[@ratrodsafrica]

Great video! Everyone seems to think the 9" is the holy grail, but everything depends on application.

[@hotrodswoodshed7405]

assembly on a convenient work surface and NOT under a vehicle IS the holy grail!

[@Trumpetmac]

Awesome video, Unc! One more history of the Ford 8.8 since you mentioned it 👏

[@paulanderson388]

The old Ford 9 inch (banjo) rear ends were used on the F-150's and Broncos until the early to mid 1980's and were very rugged and durable for towing heavy loads without problems. They were especially good for four wheel drive vehicles especially when equipped with the Trak Lock positraction unit. Most of these axles would go several hundred thousand problem free miles with minimal care. An old racers trick was to drill a drain hole in the bottom of the axle housing and tap it with a 1/8 inch pipe plug to make oil changes easier.

[@jimmfitz9828]

I am amazed at how much this person knows. Next video will be about drag coefficient of various antennas.Tony, respect to you, I am amazed.

[@3rdpig]

Great video! When I was a young man in the 70's racing Mustangs, everyone wanted the 9 inch for street/strip cars. I did multiple swaps of 9 inch rear ends into Mustangs that came with the 8" including a 69 I owned (swapped a top loader 4 speed into it too). I've currently got a 67 390 Mustang that came stock with the 9 inch.

[@thisisyourcaptainspeaking2259]

Mustangs came with 9" up through 73, didn't they?

[@nickbonvino]

Depending on engine size…351 or bigger got the 9 inch

[@troyberg65]

@@nickbonvino yea, not even all 351's got the 9. my q code 72 (351 4v) had a 8" from the factory, swapped a 9 in with a locker and 4:11's for some more fun. My dads 69 (4v 351) had a 9

[@herbthomas5097]

I enjoy watching Tony. I'm not much younger than him and I like the fact that he still does things with carbs and points. The younger generation has no idea how much better than the newer stuff. I'm a mechanic and car were better and more durable. Personally I feel they haven't made a good car since around 1985.

[@jamesbosworth4191]

You, of course, are correct. What is allowing today's cars to rack up such as incredible miles is today's synthetic motor oil. If oil hadn't improved, today's wonder cars would be hard pressed to last much longer than 60,000 miles before needing the engine completely rebuilt.

[@subwoofer8865]

I think these differential videos are great. Learned a lot. It would be cool if you talked about the Dana 60's and 12 Bolt Corporate more since you can find thousands of them in the rears of older trucks. They are probably 8 bolts lug pattern, but are still usable for a lot of guys on a budget.

[@shaunclifton5281]

Yeah , I have a factory big block 70 Dodge truck with the 8 lug Dana 60 that I plan on swapping the Eaton locker and 5 lug axles into.

[@hankblossom]

In Chevy pickups the 1/2 tons would have a 12 bolt ,6 lug axle, and 3/4 ton and up would have the 14 bolt, 8 lug axle. From about the 70's up.

[@Sak-zo1ui]

These hypoid gear axles had been around forever on bigger trucks prior. Ford and chrysler both just copied the bigger rockwell designs.

[@shaun.h.barlow]

The 14 bolt corporate is the most durable due to the third pinon bearing that does prevent pinon gear deflection under shock loading such as axle hop or tire shake put a truetrac Detroit in it and use the skinny pedal with reckless abandon and the first thing to break will be an axleshaft replace those with some cromoly ones and tada bullet proof rearend

[@guerrillaradio9953]

True. Have one in my daily C3500. Thinking about machining my own 8 bolt to max 5 adapters and running sprint car wheels and drag tires on my hotrod project just because I already know it so well and know it's about bomb proof, especially like you said, with chromoly axles, which takes 10 minutes to swap in lol.

[@shoominati23]

It's like the Big 4 Manufacturers were laying the groundwork for the Performance era of cars that were to come in the early to mid 60s already back in the Late 50's. All the engine platforms that became the big hitters for performance had their Genesis in this time, so too driveline components like Diffs and Gearboxes. Most of these Auto Execs had been Defence Staff in WW2, so they knew the virtues of Strategic Planning

[@oops1952]

Great video Unk....I learned a lot. Back in the day, I was told the posi on the 9 inch wasn't as good as the clutch type 8 3/4 on our mopars. In an automatic hemi most came with the 8 3/4

[@oops1952]

@@MrSwinger1 I picked up an 8 3/4 from a wrecking yard that had 4 spider gears. I wondered what it came out of.

[@kevinmcguire3715]

@@oops1952 They made lots of variants of 8 3/4.My dad got his beloved 65 Coronet sedan totaled by a new American in a taxicab. The Dodge coronet was a 225 slant 6 and 3 on the tree and 250K miles that he bought new. The 3.31 to 1 8 3/4 had very thin looking ring and pinion gears and I put it in my 62 D100 slant 6 and 4speed granny as the 3.9 ate too much gas as I was freeway driving a lot. It worked fine pulling my flatbottom v-drive boat for a decade .I then put it in a 1971 D100 and ran it for another 5 years.

[@kermitbearden7142]

The Detroit Locker changed that.

[@danielarney9729]

Thanks. Reminds me of when my old man would explain stuff to me, or when I listened in at the shop him shooting the shit with buddies in such a way that doesn't make you want to jump out a window.

[@Athlas87]

Finally this channel is doing the thing it can, explain why. KZbin is full of big power now why no efficient designs, you are showing what it means to know why vs how which is much more important

[@glocke380]

Reminds me of the time a kid told me his car had a 9" 12 bolt.

[@ajw6715]

I have been using ford 9" N case rears sense 1971 and haven't had 1 second of problems with them. Excellent rear end.

[@timmcooper294]

If you want to see the rear that possibly inspired the Ford engineers 30 years later, check out a Packard from the late 1920's. In 1926, Packard was the first true Hypoid rear end, and it had all the features that Ford put in the 9 inch. Straddle mounted pinion, 2 inches lower than ring gear centerline, in a beefy drop out third member. Pretty cool for almost 100 years ago !

[@bcbloc02]

Well you know Packards only exist because they wrote Ford telling him how to make his car better and last longer and Ford told them if they knew better than him they should build their own so they did! LOL

[@JrGoonior]

I read an article many years ago talking about how Fords were breaking axle shafts on hard launches. The engineers kept trying harder and harder materials and the harder the material the easier it broke. They eventually tried a softer iron for the shafts and didn't have any more problems, what they found out was the harder axle shafts weren't flexing under load and the softer more spring like one would and not break. Doing this from memory, please correct any details, thanks!!!!

[@timothyarnott3584]

Hey Tony, Tim here....yea, my 600 hp, 625 lb ft, destroyed my 12 bolt......TWICE now ('64 Tempest, T-400, 3:73 gear, 3450 with me in it).......my 12 bolt dont like my torque.......WHEN , not if, WHEN it blows again, its gettin a 9" Ford.......but i TOTALLY agree with your power level assesments, as i know.......GREAT vid!!!!....TY sir PEACE to you!!

[@amos4457]

Nice explanation Tony. The proper term for the pinion front half is called a pinion cage assy it has two tapered roller bearings in opposing each other. I agree with you on the pinion deflecting an there is a lot of pressure there but the ring gear deflects more than the pinion gear. That's why on trucks we put a thrust bolt on the centerline of the pinion in the housing an it goes flat against the ring gear to reduce the deflection. That would be a cool mod to do to these car diffs.

[@peterchristlieb]

We used the Chrysler for years, it lets you out the motor up a little higher in the chassis with out so much tilt. It’s plenty strong as long as you don’t get into tire shake

[@jamesford2942]

The 9" in a hot rod that is just a driver is overkill. It also is a problem in lightweight cars such as a Model A. The problem being unsprung weight. When your car is too light to hold the rear end on the ground the ride quality suffers. I have used quite a few 8" rears in lighter hot rods with good success. I have also used the 8.8 Ford rear which is basically a 12 bolt Chevy rear. Some parts interchange. The reason that Ford went with the 8.8 is for fuel economy and weight. It's a decently strong rear without the extra drag of the extra low pinion.

[@Canibal_Animal]

True, the pinion bearings in the 8.8 and the 12 bolt are the same. People sleep on the 8.8s

[@A_friend_of_Aristotle]

I have a 9" as a differential demo for my truck drivetrain class. It's a scaled down copy of the larger Eaton's, Spicer's and Meritor's that are used in heavy trucks. The spigot support and detachable pinion make them easy to rebuild and adjust.

[@stanwooddave9758]

The professor knocks it out of the park. Thank you (Uncle)Tony. for sharing your love of all things automobile, and all of the quirks that go with it, i.e., Ford 9" in. Rear Ends, and so much more. Some people would actually pay money for this knowledge, and Uncle Tony gives its; for the price of admission, just click on it. In my best Kojak (crime drama television series starring Telly Savalas) voice, Who Luv's ya baby! aired on CBS from 1973 to 1978.

[@ram50v8]

Good to here some one sit down and talk about this. Being a life time Mopar owner/fan, I have played with my fair share of 8-1/4, 8-3/4, 9-1/4 and Dana 60 rears. One nice thing about the ford 9 is there are aftermarket center sections that use the gm 12 bolt style ring and pinion placement. Giving you the advantages of both. When we raced dirt track cars, the drop out center section made it easier to change ratios for the track conditions.

[@hypocycloidiaspora]

Another great, informative video from UTG - now I want to go down the rabbit hole on IRS differentials and find out what their plusses and minuses are...

[@RetroAnachronist]

Super informative. Thanks.

[@kendriver9139]

Had the original gm drop out center rearend in my 55 Chevy. I could push it around with my fingers. Installed a Currie 9 inch housing with a 3.90 gear and trac lok. It took considerable effort to move around. Felt like I added a thousand pounds. I'll be pulling the 9 inch to put a big olds rear I acquired.

[@randr10]

The 8.8 is still a pretty strong rear too. One of the last cars they ran the old 8.8 on was the Trinity 5.8 powered GT500. I don't remember hearing anyone complaining about having problems with them on those cars. I've also seen guys mod their cars/trucks with the 8.8 to 800-1000hp and again don't remember hearing anyone complain about them breaking. I'm sure once you start running 8's at the dragstrip that story might change, but for any street car you can't go wrong. Great on fuel with the right ratio too.

[@jackaustin3576]

I have a 1950 Willys Jeepster which I put an eight inch Ford rear about 20 years ago....The right rear bearing leaked and a sleeve was not available so about eight or ten years ago I changed it to an 8.8 inch from about a 1980 Ford Explorer....I have had no problems with the 8.8....

[@scottwildes1247]

That was the best description of rear differentials , you did a good job at explaining the efficiency of the many choices.

[@PETERNESS]

hello from Australia UTG ,greatest auto channel on youtube , i have a 351W up front followed by a top loader and i really wanted a 9 inch LSD in back and get rid off that single spinning Falcon diff before it lets go ,i purchased a 9 LSD and paid a mechanic to fit it as i had just gone through a herniated disc and needed to do physio ,dropped off in morning and picked up in the afternoon and it was awful ,everytime i made a sharpish turn in 1st or 2nd one wheel would almost stop turning and churp churp especially around a roundabout ,i took it back and the mechanic said thats how it should be ,thats BS all i wanted was two wheels to spin ,how can i stop this wheel doing this as i made a bit of a goose of myself and the mechanic barred me from hes workshop

[@terrycarter8929]

If you have a vehicle that you want to use it on the street, road trips and drag racing the 9" rear is one of the best because you can pull the axles and remove the center section and change the gear ratio without the process of setting up the lash under the vehicle.

[@b.s.adventures9421]

14 bolt full float chev has that extra pinion bearing too. 4x4 guys love em.

[@CanadaBud23]

Rock bouncers and buggies all have them!

[@GrandPitoVic]

Another good thing about it is you can have multiple gear ratios in different carriers and depending on what you are doing you can swap it out. Put steep gears in depending on the track to get different results. Same with the Chrysler center you have there on the table.

[@jmflournoy386]

In Trans Am Javelin we had AMC Salisbury style rear end, Hotchkiss makes gear swaps much easier,(we usually changed complete rear end) but out on the course Salisbury is measurably more efficient and runs cooler but both required coolers

[@johnny0454]

Fantastic info, thanks!

[@keithmalmberg8395]

Put a match set of axles from an early Bronco in my jeep. The 9 in the rear with a high 44 in the front. It was all about "shock" load. Low speed, high torque with shock loads when the tires loose traction and then grab. Never broke the stock 35 spline BB, broke a few u joints up front....

[@proofbox]

Your case makes sense however this was pioneered by Chevrolet in 1937 as they had the same motivation . By this time in history bodies were being lower on the frame to improve streamlining . And there is a picture I have seen on You Tube where the driveshaft runs through the passenger compartment . However it was considered impracticable due to loss of floor space [ not to mention hazardous to the occupants of the car ] . So they showed how lowering the pinion gear moved the driveshaft down . This can be found by searching Jim Handy Chevrolet differential 1937 , this is also for the beginner the best explanation of how a differential works I have ever seen . Take a look you will agree .

[@UncleTonysGarage]

I mentioned the Cad/Lassale rear, which is another example of early dropped pinion design, but this video is about the 9 inch and it the specific reasons it is stronger than the others

[@robbyrob8349]

I have the Ford 9" rear in my 1974 Lincoln mark VI

[@ThePaulv12]

Stock, the 9" isn't particularly strong. It's the aftermarket that makes it great combined with the removable centre, which means it's so damn convenient. Because it is so well supported in the aftermarket, parts are relatively cheap and available.

[@MaxNafeHorsemanship]

I have never owned a Ford 9in but always heard about them. Now I know why they are spoken so highly of. Thanks for the education. Great information. Now I know why they are so good and why I will never need one.

[@pghgeo816]

Well hell, Now I want you to go deep on the Dana 60. Pros and cons. Where does it get its legendary strength? Where was it popular in racing? I get so much out of these vids where you nerd out and a specific component. U joints sizes and strengths and driveshafts materials balancing yoke sizes.

[@rockymeyers4030]

Off topic here. DDs speed shop has talked about taking a Chevy Nomad on the power tour, not the Uncle Tony charger. Has your plans changed on the project since it may not be taking a long drive in the summer?

[@steffk5878]

Gott love uncle Tony! Looks like a retired hells angel, sounds like he designs for n.a.s.a. friggin love this guy!

[@TheAyrCaveShop]

Good one Tony, I've had several 9" and still have one in a bronco...Rock solid !

[@elvispresley3340]

HA - PROF. TONY. Your knowledge never fails to impress. Thanks. CHEERS from AUSTRALIA.

[@skylarsoper241]

I always thought of jungle Jim and Vega funny car it had a raced out bbc but he switched to mopar hemi ……such a rad era of drag racing 🤯

[@craigpennington1251]

Had the 9" in my 72 Grand Torino Sport Fastback with the Cleveland, trucks, & T Birds 76 thru 78)4 of them/racing & street. The Torino 9" was used up so I took one out of a Police car a guy had in his salvage yard. It was a 2:50:1 ratio. That Torino then had some long highway legs for fast cruising without high RPM. And those 9" rears held up plus easy to work on. P.S. They need to raise the ground clearance on cars cause our roads are crap. Every entrance into or out of a business in town has right at a 45 degree v notch from the street to the driveways or parking lots. Everywhere you see gouging in the pavement because of this & damage to the cars. Plus thousands of miles of gravel roads throughout the State.

[@mylanmiller9656]

i went to a Ford Drag race seminar way back in 1968 and they explained the advantage in the 9" rear. Ford Guys knew how good the 9" was, but it was not until Gapp and Rouch used a 9 " in their Pinto that other guys realized the potential of a 9". Even Dyno Don used a dana 60 in his car and he was the Ford star of Pro stock. All Ford drag Cars were Gear jammers back then so a 9" was the diff of choice.

[@Maples01]

I've busted the pinion/ring gear on a Chevy 10 bolt, did it again on a Dana 44 in a CJ5, had the spider gear retainer pin slip out and hit the pinion on a Dana 60 locking it up on me, full floater, so I pulled the axles and towed it home.

[@mb-fs1yo]

In the middle 80’s circle track racers embraced the 9” because of the drop out centers, racers could tune the rpm of the engine to the racetracks quickly. This was especially true of classes that were not allowed to use a quick change rearend.

[@stevejarred6484]

As always, Uncle Tony, I learned a ton from this video! In fact, it made me think of "Sarah-N-Tune" who's stuffing a Toyota V8 in a Corolla and what Toyota transmission and rear axle she could use to make all work out. I guess I'd appreciate more reasons why you'd want a Ford over a GM over a Mopar over a Dana over a etc.

[@retromotors383]

Tony, you are considerably smarter than you look!😉 Keep on keepin' on!

[@sydrider6023]

This tutorial is priceless!👍

[@baby-sharkgto4902]

Awesome video Uncle Tony. One thing I did not know until recently is when you purchase a brand new 9 inch these days more often than not they will be noisy because of how modern gears are machined.

[@ldnwholesale8552]

A proper street gear set up should be quiet,ish. Racegear set up will always be noisy,, set up for performance not to be quiet.

[@GwynnOak1]

That was a very good technical presentation! Once again just a accurate assessment of pros and cons, with a interesting side of history. Bravo! You can tell I'm a dinosaur, I still use the old GM 12 bolt jackpot. The Pontiac-Olds that was top dog in the 60's, in most of your high horsepower classes. They were never plentiful or cheap, but if you were running a Chevy gasser, the only way to go. The Ford is the way to go now, given the market. Great lecture!

[@thomasward4505]

The weak link on most car 9-inch rear ends are the axles, a Chrysler 8 and three-quarter axle is way bigger than a 9-inch axle. Want you change to aftermarket axles however and 9in is definitely Superior. Also from what I've read the 9in is really a lot stronger when you get into the 513 gear ratios and 538 axle ratios but with regular Street gear ratios the friction does become an issue. But availability is key

[@bigassfordsd]

ford did use more than one axle int the 9". I know for sure that there were 28 spline, and 31 spline. Also different bearing sizes as well. About 15 years back, we experimented with the 8.8 in our circle track cars that had spools and 4:88 gears but we had problems with bending tubes if anyone bumped us. we switched back to the 9".

[@Trumplican]

a garage with NO 9" Ford rearend parts?? BLASPHEMY!! LOL cool video UT

[@IMRROcom]

I have a 8 1/4 with 3.91 limited slip in my 360 Duster A-500

[@rcnelson]

I admit that it's unclear why pinion placement matters, although I don't doubt the experts. It seems to be a matter of leverage but why a low pinion has more resistance when it's just a bevel gear turning a ring gear with the same 360 degree contact faces beats me.

[@shaun.h.barlow]

Tooth engagement 9 inch has four pinion teeth touching the ring gear because of where it is low on the ring gear also it is swimming in gear oil 10 and 12 bolts have at best two and half teeth engagement. Gail banks explains fluid dynamics in rearends to debunk aftermarket diff covers claiming lower temps due to higher capacity's on you tube

[@jamesmarze9850]

I always learn something from watching your videos thanks Tony

[@rogjackson]

Fascinating. I had not heard that take.

[@wdxwm300]

I like the dana 60 it held up great in my 1967 GTX 4-speed put the hammer down many times and changed a few clutches. I got fairly quick with that inland shifter

[@mrmidnight32]

If you had to pick 9” or 12 bolt which would you choose?

[@michaelschoeberl5716]

Question for Tony as a former wrighter is it foot pounds or pound feet the use of pound feet in reference to torque specs. Drives me nuts

[@kurtisstutzman7056]

They used to only put keyholes for the door locks on the passenger side as well...

[@EitriBrokkr]

Can you do a video on shimming the differential and checking tooth engagement and backlash? I have never found a great video on the subject

[@shotsrodder]

Great history lesson Tony 👍

[@garypeatling7927]

Thought I knew everything about this , great information i didnt know this

[@mikeskidmore6754]

The New Process 9" rear end .. Full floating axles are nice ..

[@genemartin6962]

The 9 inch Ford really came into prominence NOT in NHRA and drag racing but through those good old boys down South.....NASCAR. When the roundy round boys figured out that they could make a full floater rear end out of these things and then discovered rear end coolers they became mandatory if you turned left. They are still used in a LOT of circle track cars due to strength, gear ratios and many other reasons. They are MUCH easier to set up than a 12 inch chevy and more durable.

[@mfranzusan3014]

The 9 inch setup is considered a hypoid. The gear is not just anglular, but as you said, it's helical cut. The gears offer a wide contact to provide greater leverage with less noise, but they also slide between initial contact and when the contact is broken upon the pinion gear's revolution, you'll find the initial contact of the crown's leading contact has moved from outside to inside along the conical circumference of the pinion (if that makes any sense). It's the compromise that needs to be made with the physics required to have that pinion engage at the 5 o'clock position.

[@pauljanda5262]

Always such great content!

[@Pats-Garage]

I have a question about an 8.8 rear dif from a 04 Cobra It only has 25000 miles but I had to replace the crush sleeve and the pinion flange Did not get The reading on the rotational resistance before I took it apart. I have it in between the spec that Ford recommends for the preload 8 to 14 around 10 or 12 Ib-in for me. Everything feels smooth when I rotate it And I used gear marking compound To see the pattern at least. My question is with such low miles should I expect a wining noise from having reset the preload and not knowing what the previous spec was. And what might be a way to go about Getting it to stop. Thanks man also always find your videos super helpful And I end up learning a lot every time keep up the great work👍👍

[@shaun.h.barlow]

Crush sleeves don't go bad unless excessive wheel hop occurs or no mercy reverseis ,neutral drop on KZbin ifn u don't kno what dat is, both are driver error unless a mechanic over tightened the pinion nut after a seal change

[@speedy_pit_stop]

Loved the video. I own two of those Ford 9-inches in running cars.

[@kraftzion]

That was a cool breakdown.

[@heavymetalmadness666]

great video, but what about the very overlooked 8 in ford. I would bet a lot of people have them and just assume they have a 9 inch.

[@tjt4036]

Great video Tony. More differential videos is okay.

[@artyberkhoff8878]

Great info, you really know your hot rods!!!

[@Trikekid84]

Wondering why our 63 Bel-Air has a 9" style center section that comes out the front. It has a slight hump in the floor but not too bad for that low of a car. This car also has a X frame, which was created to get the body to sit down lower as well. Toyota used that style diff as well late 70s-mid 80s I believe.

[@carmenalexander7404]

i had a friend who had a 69 Camaro he put a 9.75 Pontiac in it. It was strong and set-up like a 9-inch Ford, but it was hard to find parts for it.

[@danhill6060]

Great video Tony thank you

[@randymagnum143]

Truck and tractor rears had pinion support bearings decades before.

[@anthonysantiago1999]

Good differential education Tone..