TH400 Shot, Need Suggestions
Thread Starter
On The Tree
Joined: Oct 2010
Posts: 135
Likes: 0
TH400 Shot, Need Suggestions So, I yanked my TH400 out and dropped it off at the local tranny shop to have them go through it and seal it up since it was leaking horribly. They called me and told me I needed to come down and look and it wasn't good... 
The tranny is wiped. Bearings are shot, case is shot, etc. They told me whoever put it together had big clearancing issues and it was a matter of time before it just imploded. 
So, here I am at a crossroads..
They are going to give me a price on a new rebuild tomorrow, but are estimating $1500-$2000 to put it back together with hardened parts and the necessary replacement parts that aren't wiped in the current tranny.
Here's some pics that were taken of a few internals...
I am looking for suggestions on getting a new th400. The car is an LT1, weighs 3800 with me in it, and you can figure close to 1000 HP at the wheels. Car is getting a big turbo and is mostly drag raced with a little street time for fun.
A buddy told me at that price, I might as well get a powerglide and move forward from there. He said I can use my current TH400 converter, but will need a new driveshaft.
Any thoughts on getting the TH400 rebuilt? Get a new one? Go with a glide?
Thanks!
The tranny is wiped. Bearings are shot, case is shot, etc. They told me whoever put it together had big clearancing issues and it was a matter of time before it just imploded. So, here I am at a crossroads..They are going to give me a price on a new rebuild tomorrow, but are estimating $1500-$2000 to put it back together with hardened parts and the necessary replacement parts that aren't wiped in the current tranny.
Here's some pics that were taken of a few internals...
I am looking for suggestions on getting a new th400. The car is an LT1, weighs 3800 with me in it, and you can figure close to 1000 HP at the wheels. Car is getting a big turbo and is mostly drag raced with a little street time for fun.
A buddy told me at that price, I might as well get a powerglide and move forward from there. He said I can use my current TH400 converter, but will need a new driveshaft.
Any thoughts on getting the TH400 rebuilt? Get a new one? Go with a glide?
Thanks!
Last edited by WhistlingZ; Feb 24, 2011 at 05:47 AM. Reason: Added Pics
This is the first time I've ever heard someone talk
about a TH400 case being "shot". It's not a wear part.
I think I would collect my basket of parts and mosey
on down the road.
Seems like for that money you could get one on a
pallet delivered, with a lot less suspicious story.
about a TH400 case being "shot". It's not a wear part.
I think I would collect my basket of parts and mosey
on down the road.
Seems like for that money you could get one on a
pallet delivered, with a lot less suspicious story.
Thread Starter
On The Tree
Joined: Oct 2010
Posts: 135
Likes: 0
the cases do go bad-broken lugs in the case-some of the larger trans places have the ability to repair some of the case problems, but way to many 400 rebuilable cores for $100 or less out there
i prob have 15- 400's and 4l80e's, i see a deal and pick it up-even a BOP can be used, they sell an adapter, or cut the bellhousing off and use an ultra bell
and no, i dont sell the cores, lol-now and then a trans shop will call and i throw them a core, and they take care of me
i have seen large bins of trans cases sent out for scrap, just to damaged
i prob have 15- 400's and 4l80e's, i see a deal and pick it up-even a BOP can be used, they sell an adapter, or cut the bellhousing off and use an ultra bell
and no, i dont sell the cores, lol-now and then a trans shop will call and i throw them a core, and they take care of me
i have seen large bins of trans cases sent out for scrap, just to damaged
Th400 cases do go bad. In your case it looks like the rear case washes spun do to a bearing failure if I had to guess. I have also seen the snap ring for the intermediate clutch break the lugs as well. Personally I always install a bearing in the back of the case and make sure to get the endplay set up with performance spec's in mind. Look up Jakes Performance for a TH400. I know he specializes in these units and his prices seem reasonable for what you get. Best of luck with your project. Vince
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Turbo spline converter won't work in a glide unless you put a turbo spline'd input shaft in it, there are quite a few on the market. A glide will run about 3k bucks though to last at the 1000+ hp level, but I'd run the glide for consistency over a TH400. Otherwise... I run a coan TH400 and it's a great trans. you might want to do a 300m input...
here's mine...
http://www.coanracing.com/Catalog.as...uctDetail=1556
here's mine...
http://www.coanracing.com/Catalog.as...uctDetail=1556
A good th400 for that power should have a bearing in the back instead of that 3 tab washer to start with. I would get in touch with Jakeshoe on here. He makes some great pieces. You will be suprised how much the TH400 can take.
Whistling z, We have 400's rated from any where between 800 hp and 200hp. Visit our website and look at them , We also have glide from 900 hp to 3000 hp. Our 900 hp 400 with a brake is less than they want to rebuild them and we do not need a core.
Greg
FTI
1-866-726-8358
Greg
FTI
1-866-726-8358
__________________
FTI COMPETITION CONVERTERS AND TRANSMISSIONS
"IT'S NOT CHEATING, IT'S THE COMPETITIVE EDGE."
1-866-726-8358
info@ftiperformance.com
FTIPerformance.com
FTI Converter build sheet
FTI COMPETITION CONVERTERS AND TRANSMISSIONS
"IT'S NOT CHEATING, IT'S THE COMPETITIVE EDGE."
1-866-726-8358
info@ftiperformance.com
FTIPerformance.com
FTI Converter build sheet
