1971, 350/270, 400 Auto I am going to attempt rebuilding the automatic transmission. I will be using the Haynes manual for this. Anybody rebuild there tranmission? Any advice would be greatly apprieated. I would like to know what rebuild kit I should use and if I sould go with a stock torque converted or an after market one.

 

Tom;

I admire your attitude and self confidence. I just recently had my TH400 rebuilt and it's OK now but dealing with the shop I chose was not an enjoyable experience, and it cost me twice what I had budgeted. I do have expereince with rebuilding TH350 transmissions and I wish now I had done what you're doing. At any rate, I don't know about a Haynes transmission manual specifically, but my expereince with Haynes manuals generally is not totally favorable. My suggestion would be to get the manual by Ron Sessions, "How to Work with and Modify the Turbo Hydra-matic 400 Transmission." The guy knows his stuff and explains everything clearly and thoroughly. The book also has lots of good-quality photos. It costs about $22. For parts, I'd go with a Trans-Go kit. Check your Northern Auto Parts catalog for great prices. If you don't have a catalog, e-mail me and I'll give you their phone number. I'd also strongly encourage you to install a shift improver kit from Trans-Go while you're at it. You'll love the way it makes the transmission shift and it will also make your transmission last longer. Your question about torque converters, I assume, relates to stall speed. That will be predicated on your engine. The purpose of changing your stall speed would be to get the engine into its power band for launch. If your engine is stock, use a stock-spec converter. If you plan on changing your engine specs, change your converter accordingly. One final suggestion that has always stood me in good stead when working on my cars, or anything else for that matter: Use the 40-40-20 rule. Spend 40% of your time thinking about the project, and doing research; 40% of your time getting together the parts and tools you'll need; and 20% actually doing the job. It'll go smoother, you'll enjoy it more, and it will turn out great.

 

I rebuilt my first one using the haynes manual and it couldn't have been easier. The manual takes you step by step right through it, with great detailed pics along the way. I went with the trans-go kit from Northern Auto Parts as well. http://www.northernautoparts.com/ I use them for a lot of my parts purchases. Their prices can't be beat. Take your time and keep things clean and you'll be alright. Good luck.

 

I'm going to go through my 72's TH400 one of these days(months,years!). I have the trasnny out already and I bought he B & M Transkit, which has everything but a filter in it. I heard that B&M makes high quality parts so I'm hoping that there won't be a problem. I have a couple of videos on th400 rebuilding too that help.
Gary

 

yeah i rebuilt a turbo 350 in my camaro when i was 17 and let me tell you i had parts everwhere :yesnod: i had alot bench space and just uninstalled one part at a time and moved it down the bench and then reversed the order putting it back together,my parents werent too happy when they came home from vacation and saw it in there basement all apart..you can do it just follow manual..but id never do another one again its something didnt like to do.

 

I have done two auto transmissions. I got the ATSG book (Automatic Transmission Service Group). You can get them from Napa, and form transmission parts places. Get you a good quality seal and clutch kit, and if you want a shift improver kit, get the Trans-go kit, not the B&M. I understand the B&M gives slightly crisper shifts, but is not as good on the transimission. Take your time when you take it apart, take each part out and very carefully put it down in the same orientation as all other parts so you know, without question, the order and orientation to put them back in! Very important! A single torrington bearing put in backwards will prevent you from putting the pump back in and you will have to take it apart again and try to find out which part is backwards. You will want to rent a couple of tools, check your book to see which ones.

It's really not that bad.

John.

 

Clean bench space and lots of clean rags. I have a 73 GM overhaul manual which is good.

 

Thank you for all the great info. You have really fired me up to tackle this job. I will be purchasing the Trans-Go rebuild and shifter kit. A far as manuals go I think I will look at each one and decide from there.

 

Glad to hear you're going to do it. Remember, even the transmission experts had a time in their life when they didn't know how to rebuild one. They had to learn, you can learn just as easily. Good luck and keep us posted.