DIY TH400 rebuild yes you can. Part 1

[@timweb1510]

Good work man. It’s great to have all that open space to work in

[@corryn00]

depending on your horsepower goals, the switch pitch will work like having a high and low stall converter feeling.

[@louisveni9754]

A switch pitch was used 1962-1965 maybe but all it is the torque converter with 2 selectable canes low stall and high stall love your Chanel I’ve rebuilt 2 since watching this rebuild thx for showing how easy it is

[@HeadFlowInc]

Louis Veni Thanks for the kind words and support! I found out the odd setup was an option Pontiac used to alter the ignition timing based on valve body pressure? It must be pretty rare? Thanks again for watching and the feedback!!! Congratulations on the 2 builds 👍. JD

[@karlmarx560]

steeley dan in the background. reminds me of my pops. i wouldnt be here if he was still around. thanks guys

[@265chevy]

I am enjoy this video set because i want to rebuild my 350 turbo trans but i have never done it before so thanks for the videos

[@HeadFlowInc]

265chevy The TH400 is easier to rebuild, the only real special tool you need is a harbor press, and even that isn’t 100%. Needed. The TH350 requires some specific tools for the process.

[@fredc8618]

@@HeadFlowInc what do you need the harbor press for?

[@HeadFlowInc]

Fred C You have to compress the release springs in the clutch release assemblies. kzbin.info/www/bejne/j2HCc2Oji7qKa5I

[@nsboost]

You can make the special tool you need with some nuts, plates of steel and all thread. Or buy one for $50

[@tombrown8829]

This is nothing like your th350. Sorry but nothing for a 350 will help with a 400.

[@jjock3239]

I don't have time to watch your next part yet, but if, as I suspect, this is a switch pitch tranny, I'm all in. I have the right case, and I want to convert to a switch pitch converter. I had one in an Olds Toronado, and I loved it. Great video. Bob

[@HeadFlowInc]

j jock Turns out this is not a switch pitch TH400, they only made them in the mid-1960’s like 64-66. The extra sensor and wire was a different feature not all TH400 had. At the moment I can’t recall what it did, but it had something to do with monitoring shift pressure based on engine vacuum? I’d have to look it up again. Thanks for watching! JD

[@jjock3239]

@@HeadFlowInc I am aware that there was something else that required two wires into the transmission, but I had never seen one until your video. I have the correct case to install a switch pitch, but I haven't been able to find a switch pitch core. It isn't the highest priority for me right now. Bob

[@HeadFlowInc]

j jock I wish the aftermarket would bring back the switch pitch, it was a great idea! Best of both worlds JD

[@jjock3239]

@@HeadFlowInc There are a couple of companies that are rebuilding switch pitch converters,one in Phoenix. I can find the name if you are interested. My switch pich was in a 67 Toronado. Some 67 Olds, and Cad cases are olso candidates as well. Bob

[@HeadFlowInc]

j jock You’re right, the Switch Pitch was from 65-67 non-Chevy GM cars. I’m going to start looking to see what it takes to build an SP TH400. It would be nice to change between a 2000 stall to a 2800 stall with a flip of a switch. Thanks for the feedback I appreciate it! JD

[@skylinefever]

I never learned how to work on automatic transmissions. My reason was that I just wanted to get out of school and get back to the auto repair business. 4:20 either that, or the old part is really bent out of shape. It is a bit like trying to pull a lifter that was completely destroyed and will not come up the lifter bore. Instead you are forced to remove the cam, then figure out where the lifter fell out. 11:50 You could look up people who own a GMC RV with the Olds 455 and TH425. They get the most benefit from retrofitting the switch-pitch converter since they can't just buy an overdrive transmission. That means many of them have become experts in switch-pitch converters. I thought about getting one of those GMCs, but when used Winnebago Rialtas went way down in price, I wanted one of those instead.

[@HeadFlowInc]

Skyline Fever I’ve posted some feelers online to see what I have here. My Haynes manual doesn’t mention anything like this setup as far as the extra solenoid. Interesting for sure! I bought a new 3/8” 12 pt socket this morning, the socket I usually use to remove the center support bolt was slipping yesterday, that’s why I didn’t get very far. 👍

[@skylinefever]

I just had another idea. Could this transmission have been used with a diesel engine? Before transmissions were computerized and needed to use engine vacuum, auto manufacturers had to invent something because diesels don't produce vacuum. Since that transmission was rebuilt once, it wouldn't surprise me if 1970s Olds diesel parts were inside of it, but the rebuilder simply left those parts inactive. In order for some vacuum operated devices to function with a diesel, a mechanical vacuum pump would be driven by a belt.

[@HeadFlowInc]

Skyline Fever Turns out its some weird switch Pontiac used to add/subtract ignition timing based on valve. Body pressure.. New to me I’ve never heard of it before.

[@skylinefever]

I'm glad you found the answer. There sure were a lot of weird smog devices on 1970s engines and Pontiac was no exception.

[@tombrown8829]

I had the GM factory class for this gbx. It was used behind the v 12 jaguar engine . it's easy to o haul , less than 3 hours if you're dedicated. And it's a strong trans especially if you add the extra springs .

[@dalevackar182]

In what part of the transmission do you add these extra springs?

[@thehaitianarab]

Watching live from Kansas City 😎😎

[@HeadFlowInc]

This crazy snow and ice before Halloween sucks! Thanks for watching stay safe! JD

[@str84rm916]

Thank you for the videos! They are coming in handy as im replacing the transmission on my airstream 345 on a chevy p30 chassis with a 454 and th400 transmission. The transmission started going out in Denver colorado and now im stuck im kansas city MO having huge transmission problems

[@HeadFlowInc]

Iosif Caza WOW being stranded on the road stinks. Are you rebuilding it now on the road? I’m not an expert but if I can help let me know! JD

[@str84rm916]

@@HeadFlowInc i could definitely use some help as of right now. I picked up a used trans from all star auto and installed it but its giving me problems as well... So im stuck. The rv is parked off of manchester and 86th

[@HeadFlowInc]

All Star should warranty the transmission but dang sucks to swap it again. What’s the transmission doing?

[@str84rm916]

@@HeadFlowInc it's leaking or should I say pouring transmission fluid from the front seal I'm assuming and it's strange because I change the front seal for the new one on I called All Star and they don't have another one but they said it was broken I can bring it in the thing is I needed transmission I have the old when I can rebuild though

[@HeadFlowInc]

I just don’t have a shop setup to try and rebuild it, I can ask around and see if I have options.

[@timferguson1526]

Question: if a TH400 previously had a B&M Transpak installed… the metal plates are different. Are the gaskets different too? Would the rebuilder need to get a new Transkit for those gaskets? Thanks very much for this video series!

[@HeadFlowInc]

Iirc the B&M shift kit used larger passengers in a couple spots in the separator plate. I thought they used standard valve body and case gaskets. Please do more research to verify they use standard gaskets. JD

[@tombrown8829]

There are several versions of wiring in th400. You should go with the corvette version.

[@timferguson1526]

Question: Do you have to take the valve body off to rebuild the transmission? Thanks

[@HeadFlowInc]

Yes because you’ll need to take the Center Support bolt out; it’s under the valve body.

[@timferguson1526]

@@HeadFlowInc Thanks and thanks so much for making these videos, you’ve given me the courage take these automatics apart and learn to work on them! I’m sure I’ll be back!

[@maxypooh]

Just did my first and just fallowed tci steps

[@HeadFlowInc]

Good info, thanks for the tip! Good luck on your project! JD

[@randsautos]

That is a Rolls Royce Trans, look on the bell housing they have a RR made with welding

[@coleschott007]

Way to Go Kansas City!

[@tombrown8829]

Re program the governor springs for higher shift speed.

[@jonathanmcelhanon6445]

So if my truck is rolling backwards in drive.. is it possible that it could be the governor

[@HeadFlowInc]

Doubtful, rolling backwards in drive when the engine is off is normal. Some vehicles will roll backwards even when engine is running if the incline is steep enough. I guess I need more detailed information? JD

[@antonio_lujan]

I have a leak coming from the passenger side of this transmission. Besides the pan and gasket, would there be any other place trans oil could leak from on the passenger side? It seems to be coming from the trans oil bolts.

[@HeadFlowInc]

Antonio Lujan Sr Most common would be the dipstick tube or line fittings running down collecting on the gasket running around the pan. TH400 If it’s a TH350 dipstick tube/seal, kick down cable to case seal or line fittings.

[@antonio_lujan]

It is a TH400. Can you direct me to any online diagrams that would picture the location of the dipstick (Filler Tube) location? I'm very new to this. Thank you.

[@HeadFlowInc]

Antonio Lujan Sr Try this link, it shows the dipstick tube, modulator valve and transmission lines to the case. goo.gl/images/27rJ3c

[@beauepperson2641]

I don’t understand the doing everything one handed?

[@HeadFlowInc]

My Right arm and upper Right extremity is partially paralyzed so I have to find ways to make it work. Thanks for watching and the feedback! JD

[@beauepperson2641]

@@HeadFlowInc omg I’m sorry sir way to go doing that with that issue. I didn’t mean anything by it. Thanks for the video

[@bryanjobe7213]

Where was the filter?

[@HeadFlowInc]

The filter was removed in the previous video where I found out the transmission wasn’t freshly rebuilt as advertised. If you listen I mentioned the other video and how the pan had been off before. 👍 kzbin.info/www/bejne/g5_Go5qjjalom8k

[@bryanjobe7213]

I didn’t see the other video. I just knew when you took the pan off there was no filter. I was like oh crap

[@tombrown8829]

You must measure the end plays and get them right. No error is ok.

[@chickenfriedbobcat6090]

Did I see a blue heeler walk by at 5:29 ?

[@HeadFlowInc]

Chicken Fried Bobcat That was our old dog “Duke” he was 1/2 Minpin and 1/2 Chautauqua. We lost him earlier this year after being in the family for 17 yrs. Thanks for watching! 👍👍👍

[@chickenfriedbobcat6090]

@@HeadFlowInc Losing a good dog can be as tough as losing a family member. I've got a pack of Heelers and I don't want to think about losing anyone of them. On a side note, I'm thinking of rebuilding a turbo 400 on a 1973 Chev truck I just picked up for a farm truck. After watching your videos I think I'll give it a go. I've got 1 1/2 arms too. Bicep ripped off the bone. Thanks for the videos.

[@fredc8618]

@@chickenfriedbobcat6090 sorry about your arm bro

[@davidguajardo1105]

Yes u did

[@theaussie7160]

Fred C ...don’t hang your arms out the car window

[@TheCapitalVice]

No a switch pitch was on Buicks between 65 and 66. It was not even called a TH400. It is referred to as a ST400 (Super Turbine 400) It also featured dual sets of planetary gears. The switch controller was mounted externally and would change your stall on the TQ converter. 64 Buicks had a ST400 as well but it had a different kickdown system and no switch pitch.

[@HeadFlowInc]

ireland4ever04 I sure would like to see someone bring back the switch pitch or dual stall speed setups. Perhaps the modern lockup converters are similar but geared more towards coupling efficiency for cruising where the switch pitch was more towards improving acceleration. I bet with modern technology and engineering someone could make an improved version. Heck with all the new dump-valve technology variable stall ratings could be possible. Thanks for watching and the feedback! JD

[@joeparham2889]

If I bought a rebuilt kit for my transmission could I do it?

[@HeadFlowInc]

If it’s a TH400 it’s one of the easiest transmissions to learn. Watch all my transmission videos to see how I used my drill press to compress the springs in the drums. You’ll need regular hand tools and snap ring pliers. JD

[@joeparham2889]

@@HeadFlowInc thanks! It’s a 4t65e out of a Chevy uplander

[@HeadFlowInc]

I have no idea what specialty tools you would need to rebuild that transmission. Some transmissions require special tools for compressing inside the case. Sorry I don’t have more information on those. JD

[@dinadrawshy6449]

Hi there I have a question if you can’t answer please . Is the 1995 4.3 Sonoma engine can fit into th400 transmission on 1968 cadi or not or I have to change some stuff to make it Fit thank you

[@HeadFlowInc]

dina drawshy The Cadillac TH400 bolt pattern iirc is the same as the Buick/Oldsmobile/Pontiac. You will need a bellhousing adapter plate to safely/easily bolt to the 1995 4.3, it uses the traditional Chevy pattern. I do not recommend using the cheap plate adapters like the one from Speedway Motors, instead get a higher quality adapter with beveled mounting holes. The only exception would be if you are willing/able to modify one of the cheaper adapter plates. One last suggestion, is run a minimum of a 2000-2500 converter behind the 4.3 to make it accelerate better. 👍

[@morganrickard5032]

the dog with the sweater haha

[@HeadFlowInc]

Morgan Rickard Our little “Dukie” he was with our family for 17+ years. Great dog, Thanks for the feedback I hope you subscribed! JD

[@morganrickard5032]

@@HeadFlowInc i will be now. best video ive found yet. i would like to build or learn more about th400. im in a drag hobby and i swapped classes so now im into RWD and th400s. whats the minimum you would do for a transbrake. the 4l80e upgraded drum for 34 sprag?

[@dariomendoza1518]

thanks for Sharing!!

[@ddyeo503]

The white wire was only for emissions, putting this in a street rod you will no longer need it. But it can be left in the transmission if you want. It does nothing in the shifting of the transmission,,,,,,,,,,,,,,,,

[@tombrown8829]

Get an finned aluminum pan. Cheap help.

[@christopherhudson7465]

Dude i just subscribed

[@HeadFlowInc]

Christopher Hudson Thanks! If you log in to KZbin without the app you get to see more videos! My channel goes back 7+ years and 400+ videos to browse. Thanks again for the feedback! JD

[@ryanr9348]

Do you know the measurement from the face of the bellhousing to behind the pump?

[@McCracken_9]

I just want to find one "how-to" video without a 5 min intro of why, when, how you bought it.

[@HeadFlowInc]

Rukkkis They sell How To instructional videos you might be able to find a step by step tutorial. Thanks for the feedback I appreciate it! Good luck! 🍀

[@capcloud]

I get it. But many enjoy the story around why someone is rebuilding instead of just a step by step process.

[@greasemonkey258]

Yeah, you know you're not doing him any favors by watching the video he was nice enough to make, right? Don't be an ass, sit down, listen, and you might learn something... Maybe respect, because you obviously didn't pick that up in your youth.

[@MrLostonej]

that pan looks like a turbo 350.

[@HeadFlowInc]

MrLostonej No sir, look at the position of the modulator valve since you can’t see the bottom of the pan.

[@zachreese6540]

No it doesn't. Hopefully you've gotten an eye exam in the past 4 years