Few 400TH transmission questions please

[71CHEVYSHORTBED402]

71 C-10 402/400TH

The captions in the images below show some questions concerning the transmission filter. Help/clarification appreciated. The last image is just for "pretty". I cleaned up a dent and such. I may paint that with the transmission, pending some research. Edit: After some research, the filter is supposed to be floppy. As for the filter missing something, it's not really an issue when you buy a new one anyway. Also, after some research, no I won't be painting any transmission. They don't dissipate heat properly if painted.

This truck is under-going a ground up restoration. I'm not rebuilding the engine, because there's just 40K and it's nice. As for the transmission, it shifts like new, but there's 140K on it. In your opinion, should I have this rebuilt? I'm not aware of very good reputable shops in the area (i.e., NOT AMCO), but seems there should be one. Also, what would you expect to pay for a quality rebuild? Edit: Yep, going to have her rebuilt.

Thanks for the input.

[Alex V.]

If it's a real "ground up" I'd probably have it rebuilt. Old seals, etc. may cause problems prematurely, and less chance of leaks if done right.

[71CHEVYSHORTBED402]

Originally Posted by Alex V.

If it's a real "ground up" I'd probably have it rebuilt. Old seals, etc. may cause problems prematurely, and less chance of leaks if done right.

Thank you. I'm guessing 1000ish, but have nothing to go by at the moment.

Anyone advise on that filter, is it missing a thing or two?

[Alex V.]

I believe member Clinebarger does it for quite a bit less than a grand - 2-3 years ago I was quoted something like $900 by an AAMCO to rebuild my '85's TH400 if I did the removal/installation. A grand should be a safe number for a reputable, capable shop to do a stock rebuild.

Can't help on the filter piece - I've only had the pan off a '400 once and it was 3 years ago. I do like those embossed "Div. of GMC" pans, though!

[71CHEVYSHORTBED402]

Originally Posted by Alex V.

I believe member Clinebarger does it for quite a bit less than a grand - 2-3 years ago I was quoted something like $900 by an AAMCO to rebuild my '85's TH400 if I did the removal/installation. A grand should be a safe number for a reputable, capable shop to do a stock rebuild.

Can't help on the filter piece - I've only had the pan off a '400 once and it was 3 years ago. I do like those embossed "Div. of GMC" pans, though!

Thanks for that. Say, the primary question is answered, the filter is supposed to fall to the rear. http://www.pirate4x4.com/forum/gener...lter-like.html

It is supposed to be like that. The handful of TH400s I have taken apart have been like this and I have been told it is so that the filter can "droop" down to get ATF from the bottom of the pan. Whatever the reason for the filter being designed to flop around is I can see no reason that you shouldn't shim it up to be stiff so long as it's still submerged in ATF(which i'm sure it will be).

[YoungPup1977]

Nothing wrong with the filter. Most of your new 400 filters are that way. it is new right ?

As far as the bolt that holds the filter, no washer is required. the pan in the pic is not a deep pan so all you would use is the bolt pictured and the filter would angle towards the rear of the trans...this is normal.

[71CHEVYSHORTBED402]

Originally Posted by YoungPup1977

Nothing wrong with the filter. Most of your new 400 filters are that way. it is new right ?

As far as the bolt that holds the filter, no washer is required. the pan in the pic is not a deep pan so all you would use is the bolt pictured and the filter would angle towards the rear of the trans...this is normal.

The filter might be say 6-8 years old. I understand the filter now. Thank you

[YoungPup1977]

Did you go to any local transmission shops to find out a price on rebuilding your trans ? Trans rebuild prices will vary from one area to the next.....