Ford C4 Transmission How To Fix Shifter Leak

Episode 175 Autorestomod
The Ford C4 Transmission is prone to leaking around the shifter shafts. Larry Shirley and Jeff Ford give you tips and tricks for how to make a good repair, as well as places to get the parts you need to get the job done.
Home page: www.autorestomod.com/ Rate, ask questions, we are very good about responding!
Thanks for watching!
Jeff Ford Contact:
[e-mail]
Sponsor:
www.nationalpartsdepot.com
Tools:
Basic Hand Tools
Parts:
C4 O-Ring (O/D) .650/ (I/D) .3810
The shift linkage nut(inner) needs to be torqued to 12-16 ft lbs.
The valve body bolts are torqued to 10 ft lbs.
The pan gets torqued to 12-16 ft lbs. With the thinner than stock pan gaskets they are selling these days, I think 16 ft lbs is a bit much.

[@wreckanchor]

This video was a HUGE help to me and solving my leak on my C4 in my 66 mustang thank you.

[@MrDLRu]

For those of you that care....The shift linkage nut(inner) needs to be torqued to 12-16 ft lbs. The valve body bolts are torqued to 10 ft lbs. The pan gets torqued to 12-16 ft lbs. With the thinner than stock pan gaskets they are selling these days, I think 16 ft lbs is a bit much. Also, there is no way to cause the check balls in the valve body to move from their intended position. One would need to split the valve body to accomplish that.

[@AutoRestoMod]

+MrDLRu Thanks for that info! We'll put that in the about section.

[@MrDLRu]

+AutoRestoMod Muscle Car Resto and Modifications That's great, you guys took care of that fast. Here's a helpful hint from my recent seal replacement job(71" F100): With the shift linkage rod disconnected, move the shift lever(at trans.) all the way forward(toward front of vehicle) so that the valve piston in valve body clears the transmission housing and makes valve body removal a little easier...May also prevent damage to that precision ground piston.

[@bigboyzguns8164]

Just went out to my 65 Falcon, put in drive and no joy, checked fluid and empty again. Time to do this. Thanks for the video.

[@DecepticonBorowka]

Thanks guys, that was very helpful!

[@stevelawrence2546]

Nice and informative video! Thanks for sharing.

[@RamSkirata]

thank you for the video. It helped me a lot!

[@ringoringo8000]

I don't like this guy..... But I really like this guy... No BS... Straight to the point !!!

[@AutoRestoMod]

I am...confused.

[@ringoringo8000]

@@AutoRestoMod Nothing bad... I mean, like when you have a hard ass Father, you hate how he comes @ you... But his genius makes you respect and love the ol' man... Wrong words used I guess..

[@kevinlane6639]

Thank you been looking for a good video on how to do this and you explained it well, now off to do the same for me 73 Maverick

[@BlueDevilGaming]

That's what I came here for! Same car lol 73 Maverick 302

[@scootergeorge9576]

I bought the seal set from Summit. The tricky part of this job is getting it back together. First mistake I made was not getting the park paw linkage piece in place. Fixed that and then the shifter jammed. Fixed that and was about to button it up and found the kick down linkage jammed. Getting that properly aligned in the valve body was a bit tricky. Got the old '65 Mustang back together and it looks pretty oil tight for now.

[@LCWoodworking]

Hi, do you have a part number for this?

[@scootergeorge9576]

@@LCWoodworking - Here's the seal. Timken 240816 -Transmission Shift Shaft Seals - You also need to change the O ring for the kick down. Take the old one into a book hardware store like Ace and they can match it up. Or NAPA.

[@scootergeorge9576]

@@LCWoodworking - Summit part number is ATP Control Shaft Seals FO-15 - This includes the O ring for the kick down. It's only 3 bucks but shipping is more.

[@LCWoodworking]

@@scootergeorge9576 thank you!

[@robertclymer6948]

Dang, how did I miss this video? I have a C-6 and will be doing this same thing. Nice tip on the valve body removal and handling cause of the check balls. Old video, but very relevant to a C-6 also. Cheers from Motown!

[@AutoRestoMod]

Thanks Robert!

[@conchitogarcia7791]

My 1967 Mustang C4 had a leaky filler tube. I replaced the pan gasket, the linkage seals. My filler tube was twisted up.

[@cecil6711]

I like how Larry gives you a good ribbing in every video.lol Thanks for the great video. :-)

[@jewllake]

yup had to do this twice already on my 64 Galaxie. Only leaks when parked not running.

[@shawnmiller9381]

Cheap and shitty reproduction shaft seals is all.

[@hughphillips67Mustang]

Do you have any videos about the c4 transmission kick down cable adjustment????

[@rdbierma]

How do you position the top side of the shifter arm? I don't see where it's supposed to fit.

[@breakingandfixingstuff]

I couldn't find the replacement o-rings on eBay, but I did find them online at Rockauto. I also found them at Value Auto. I had to find them for '67 Falcon on the website and then show the parts girl the part number since nobody could find it on the store computer.

[@AutoRestoMod]

Glad you did find them!

[@breakingandfixingstuff]

@@AutoRestoMod I didn't have to pay for shipping either. Now I just hope they work.

[@SoyPiedra]

Great video guys!! Listen...I have a 65 Ford Galaxie with a 390 cid. Any way you can explain (through a video) how to change all the fluids on the vehicle?

[@AutoRestoMod]

+SoyPiedra Well, never thought of that Soy. We'll have to pass it around the crew and see if they feel there is justifiable interest.

[@classicsurvivor]

You should of mentioned the importance of torquing the valve body down to the proper inch pound value. People over-torque the screen and valve body values all the time. This pinches the valves inside the valve body and causes them to not be able to move like they should, and it shortens the life of the transmission drastically. Super important detail on valve bodies.

[@AutoRestoMod]

Good point Grigsolove. Glad that you brought it up!

[@hughphillips67Mustang]

What is the purpose, for lack of a better term.....for the "plug" to the left of the shifting device for? That is what seems to be leaking on mine. Can I take it out and thread tape it? And put it back in? Or is it a setting for something internal.

[@LexMartain]

At 10:15 there is a spring loaded disassembly, no mention of how to reassemble. I am struggling to get my shifter to work now(valve body still off) . No spring preload on assembly , whats up ?

[@adriannanavarro1032]

Hi I recently bought a ford mustang 1970 with a leak in the transmission. We changed the oil filter, cleaned the oil pan, and installed a new gasket. It kept leaking so we bought a new gasket and it still leaks, any answers as to why?

[@vincepinault395]

Thanx for posting . This was enough info to get the job done. If you have any info on how to UN-GLUE door glass for a 69 Fairlane, that would really save y bacon this week. I glued the brackets in the wrong position.

[@AutoRestoMod]

Ouch, sorry to hear! We'd recommend talking to a glass shop and see if they have any tips. That is what we'd have to do.

[@shawnmiller9381]

Glue?

[@shawnmiller9381]

You'll need a thinner to cut it, but they're not supposed to be glued in.

[@jefflippencott4803]

Hey Guys... I have a 1966 Mercury Colony Park Wagon that is leaking in the same spot. Would the procedure be the same for the Mercury Marauder Engine?

[@sbauman67]

I am having a problem after the install, I replaced the C4 selector shaft and bracket seals (ATP control shaft seals FO-15), which required me to remove the fluid, plan, and gasket and then the valve body. When removing the valve body I did not see any springs, balls, or pins when I removed it and the install of the two new seals went fairly easy. When putting the valve body back I only had a little trouble getting the linkage and spring plunger to engaged the kickdown properly but after a few attempts got it. I replaced the filer, ensured the pan flange was flat and level and before resecuring it to the transmission with a new pan gasket. I filled the transmission with some fluid, checked for leaks and found now, phew, and the started her up and let her warm up to normal operating temperature and then rechecked. Of course it needed fluid but when I added fluid it started coming out of the overflow tube on the drivers side of the transmission just above the selector shaft and bracket. I am not sure what to investigate next? Anybody have any ideas? What could I have screwed up. I did not take the valve body apart, i.e. split the two metals halves that make up the valve body. Any help would be greatly appreciated.

[@AutoRestoMod]

Might look at the dip stick and make sure it is the right one for your applications.

[@jeff95519]

While you where there you should of mentioned how to drain the torque converter and band adjustment. Also on Ebay are new pans with a drain plug to make it easier to change fluid.

[@AutoRestoMod]

Jeff Driver Well, that is another video idea for sure; thanks for the idea. The transmission is in really nice shape and has very few miles on it so we subscribe to the "if it ain't broke don't fix it" thought here. Thus the only fix in the works was the leaking shifter.

[@nancybates7015]

AutoRestoMod Do you really need to pull the pan off the transmission if it is only the O-ring that is causing the leak?

[@AutoRestoMod]

Nancy Bates There are two o-rings, one inside and one outside. Being unsure of which was bad (it can be either one) we chose to go safe and replace both.

[@ezekielmartinez1424]

Thanks for the video. I’m pretty confident I can handle the leak on my 64 falcon wagon. One question, how can I identify what transmission I have so I can purchase the correct gasket and filter ? Thank you

[@AutoRestoMod]

www.fordification.com/tech/transID-auto.htm if this isn't helpful email me at [e-mail]

[@351clevelandmodifiedmotor4]

Inside the servo there's a tag that has all the identification of the transmission

[@rickhgrv]

Great video but one question did you encounter any check balls!!

[@AutoRestoMod]

Not that I recall. But that was a while back LOL

[@trippcorbin8850]

I have an old 67 mustang with a c4 that has been sitting for 20 plus years. Any tips for getting the transmission prepped to move again or to make sure it is in working order still? Got the engine started and running last week and the rear axle turning too.

[@AutoRestoMod]

Check the fluid, if it is not burnt (dark and super stinky), you have a fighting chance of it going with no issues.

[@redfirefox3568]

My shifter in my C4 started leaking too. I used ATP 205. Poured half a bottle and the leak stopped in a couple days. Still leak free after 4 months. It was a small leak with a couple drops per day.

[@AutoRestoMod]

Glad that it worked for you! Lets hope that the seal stays sealed. C4 C6 are pretty bad about leaking around the shifter!

[@shawnmiller9381]

When you pour in fluids that clog things up - expect more problems in time.

[@redfirefox3568]

Still leak free after almost 3 years.

[@lfranco0070]

Just bought the ATP 205 to try it in my C4. This doesn't seal up by clogging up the leak, it's a rubber seal conditioner/renewer, as long as the seal is not cracked, damaged or too far gone, it may restore sealing ability. Scotty Kilmer also recommends it to make your suspension rubber bushings last longer. I'll report back after the ATP 205 😁👍

[@krystopherthomas6946]

​@lfranco0070 so how did it do? I'm having the same issue in my 64 Tbird

[@PHCBILL]

FWIW....If the front band breaks on a C4, there is a replacement band called a "zip band" that the end is on with a dovetail fixture. you don't have to pull the trans to replace it, just pull the broken one out, and thread the new one in, and adjust it.BF

[@MrDLRu]

+PHCBILL Bogus info...Just Googled " zip band " and " transmission zip band "....Zippo

[@shawnmiller9381]

Awesome!! Where can you buy them?

[@brunoburtoni8479]

Is that down downshift lever at the 12 min Mark?

[@AutoRestoMod]

That is the main shift arm.

[@philnovellino8355]

I have a 1965 comet, just had the c4 rebuilt, when I started to do my shifter install I found that the shift lever will not move through the gears. It moves on click but that's it. Any ideas?

[@AutoRestoMod]

Not really. I'd post up on the Falcon forums or the Falcon Facebook groups and see. I just don't have a lot of experience building them.

[@lee05lee]

How R you guy's doing , quick ? ..How long is that driveshaft, ?? Also how long would the Yoke..

[@AutoRestoMod]

lee05lee Fine. We'll be covering drive shafts soon so stay tuned.

[@AnubisXII]

Hey man. That o-ring that you were talking about at around 11 minutes into the video... Were you able to find out the "sealing procedure"? What keeps that from leaking? It seats too deep (like you said). Mine leaks like half a dog and it just seems like somethings missing.

[@AutoRestoMod]

I think a new case may be the only answer. Ours started leaking again about three months later. Not a ton, but marking the drive. Time can be kinda cruel to these old gals.

[@shawnmiller9381]

Shitty reproduction shaft seals. Oil seals before installing, but dry install the outer of the non-oring seal and maybe add a slight of sealer.

[@BenG123]

Is everyone using 12lbs? Coming from a modern car where I torque to 65 INCH lbs, 12 FOOT lbs seems like too much. Also can you do the OUTER shifter o ring without removing the valve body?

[@AutoRestoMod]

The whole arm has to come out.

[@joaopinola8578]

Shawn Miller, Hi ! I have a 66 Mustang and in Brazil we don’t have the oil type F. Are there other options ? For example, Mercon or Dextron that I can use ? Thank you !

[@AutoRestoMod]

Neither of these will work. You may have to get it shipped. Or try a Ford dealership. That is where I have the easiest time getting type F

[@joaopinola8578]

Thank you very much !!

[@zeffmoreno3200]

How difficult is it to do the selector shaft seal on an FMX trans in a 71 Mustang 351 C.?I have not done more then change filter kits and tail shaft seals before

[@AutoRestoMod]

I haven't messed with the FMX. It may be very similar to the C4 and C6.

[@zeffmoreno3200]

@@AutoRestoMod I believe they are but the videos I've seen show two different ones .this one you have no choice but to go inside of it ,others vids I seen you can replace smaller seal without dropping the pan.

[@351clevelandmodifiedmotor4]

First thing first establish where the leaks coming from, my c4 seems to be leaking from the servo what ever that is, where I'm from a servo is a gas station, my c4 leaks over time plenty onto the headers and of course when I start it up and warm it up I have plenty of smoke burning off the exhaust, that sux

[@AutoRestoMod]

The servo is the round plate on the side of the transmission it should have 4 bolts on it. You may just be able to get away with only replacing the gasket on the servo and that could stop the leak.

[@shirleywilliams5124]

Is this the same type of c4 i have? I have a 1979 ford f100 4.9 liter with a automatic c4 tranny, that has a leaking seal and on the side by the shifter? Where do i find the exact o rings for this truck😁🤝?

[@AutoRestoMod]

It will be the same at the shifter. The tailshaft is the only difference.

[@j.r.thompson5950]

In an automatic transmission they use a very light weight oil/fluid. In a manual transmission they use a heavy weight oil/lube by comparison. What is the main reason for that? can a lighter weight oil/fluid be used in a manual transmission?

[@AutoRestoMod]

Newer manuals use a lighter fluid mostly to help with parasitic horsepower loss. This started with the T5 (I think) Many use ATF.

[@kingleo7261]

The transmission filter gasket? Do I have to put gasket sealant on that just like the transmission pan?

[@AutoRestoMod]

Don't do that. It should come with a gasket if one is required, or an O-ring.

[@kingleo7261]

@@AutoRestoMod Thanks a billion!!!!

[@charlesprisco7610]

Hi, what type of fluid is used in 1966 c-6 ford galaxie 390 trans ? thank you

[@shawnmiller9381]

Ford Type F only, unless you want it to behave like a piece of shit GM trans. then use their clogging up graphite loaded newbie crap which is type F with graphite in to clog shit up.

[@joaopinola8578]

Shawn Miller, Hi ! I have a 66 Mustang and in Brazil we don’t have the oil type F. Are there other options ? For example, Mercon or Dextron that I can use ? Thank you !

[@Bino-zm9bl]

Did you use the RTV during this?

[@AutoRestoMod]

Just a thin skim coat to hold the pan gasket.

[@shawnmiller9381]

Note: most companies sell crappy shaft seals. May be best to custom order one to your liking maybe even modify.

[@AutoRestoMod]

Yeah, we bought from a transmission company on eBay...and... well...it leaks.

[@dougcoleburn1579]

Autorestomod Manic Mechanic Gasoline Media hey Jeff was getting ready to have a trans shop do mine. But looks like yours still leaks even with new seals?

[@briangillen2052]

Jeff - you lost me at the end when you talked about moving the shifter to get the valve body back in... Can you explain, please?

[@AutoRestoMod]

Jeff: There was no good way to show that with it on the lift and in the car. The arm is spring loaded and in order to get the trans to work, the arm needs to be "pushed" or "clocked" forward to put tension on the park mechanism/spring. We're looking at doing a bench build of a C4 soon and I plan to go into this in more detail.

[@briangillen2052]

Okay I’m finally in the middle of doing this. Which arm is spring loaded?

[@mattfstephens]

I feel like the vid sped up and chopped out some of the most important reinstalling keys. Im on to another vid.

[@Brownies711]

How did you get that nut off to take out the shifter shaft? I'm doing this same fix right now and can not get off that nut and am worried about stripping it

[@AutoRestoMod]

isaiah gentry Which nut? Can you send us a pic to: [e-mail] ?

[@thinzzelle]

+AutoRestoMod Muscle Car Resto and Modifications u ever figure out what size that nut is?

[@AutoRestoMod]

interior nut is a 7/8ths

[@thinzzelle]

Thanks!!

[@shawnmiller9381]

Watch out for anything reverse threaded. Check thread spirals if possible. Other than that a crows foot/ line wrench may help.

[@bunedox2878]

How similar is this on an E4OD?

[@AutoRestoMod]

Not sure, I have never opened up a E4OD.

[@rdbierma]

Where can I get that shifter arm "O" ring? I've searched high and low and can't find it.

[@AutoRestoMod]

We got ours from eBay.

[@MrDaveGeneric]

How weird is this... I'm doing the same thing today...lol... on the 55 Fairlane... I BTW love the Wagon... I missed a 67 not that long ago... :(

[@MrDaveGeneric]

oh yea I don't have a "Larry"....or a "Larry Lift"... you got off easy on this one there Jeff...

[@AutoRestoMod]

Dave Generic Yep. Normally we would do that on the floor. But when you can get a lift to do one...use it.

[@AutoRestoMod]

Jeff loves him some 55-56 Fords! The wagon will get some more love as the month roll on. We plan to upgrade to power steering, cruise control and an AOD.

[@freedom0226]

theres only one thing i dont like at the most important parts you play music over it instead of describing in detail what is going on.

[@AutoRestoMod]

We understand your concern. If we play music, it is a spot where we are working and no explanation of the task is really necessary. We try and not play the music over the talkie parts in the tech sections.

[@freedom0226]

AutoRestoMod i must disagree i am doing this job now based on your video and forum notes but this is the part i dont want to mess up and no one is describing it in detail . when you say " something sounded spring loaded " it would be nice to describe it so i can put it back the same way. i am going to do this job this morning and i will go verrry slow but it would have been nice if you would have covered that part , none the less good video.

[@freedom0226]

AutoRestoMod i am doing this job right now and this is why its important for a newbiee that you covered it all. i cant take the big nut off on the inside what are you using for leverage on the other side ?

[@freedom0226]

freedom0226 just wanted to update i managed to take off the nut by having a 22 wrench slightly tilted thus giving me enough clearance to get a good turn. def important stuff

[@AutoRestoMod]

freedom0226 It was impossible to shoot up in the transmission and we weren't sure what the noise was from. Keep in mind that we are not a transmission shop; just guys that enjoy working on our own stuff. It turned out to be the transmission tension spring for the shifter.

[@douglorimer5985]

Well guys I'm curious please tell me you weren't dumb enough to put RTV silicone on the gasket event C4 automatic transmission. I like to think you know better, and that includes carburetors also if that's silicone gets in those passages you might end up throwing that transmission or carburetor for that matter in the garbage.

[@AutoRestoMod]

Nope no RTV.