CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Of TH400's and torque converters

dremu

Officious Thread Derailer
GMOTM Winner
Joined
Feb 27, 2000
Posts
16,370
Reaction score
1,128
Location
East of San Francisco
Just yanked the '400 out of my CUCV. I note on top it says "HD". This make it anything special, like is there actually a TH400HD? Wouldn't happen to be a TH475, would it?

Also, the torque converter has SIX bolts, and not three, like my TH350's and the other '400 I've pulled. Is that weird, or in line with the above?

Finally, what FREEKIN IDIOT at GM put *some* metric hardware on this thing and some SAE? :doah: :mad:

-- A
 
Yes, TH400HD for 4x4 use.
Thicker casting IIRC.
No, not a TH475.
Six bolts corredt for the TH400HD.

All of the GM idiots.
(seriously, global economy, low cost, outsource parts, etc,etc,etc.)
 
Goose said:
Yes, TH400HD for 4x4 use.
Thicker casting IIRC.
No, not a TH475.
Six bolts corredt for the TH400HD.

All of the GM idiots.
(seriously, global economy, low cost, outsource parts, etc,etc,etc.)

Well, I could but hope for the '475 :)

And as for the metric part ... just, grrr.

Thanks!

-- A
 
the HD does mean it's a 475!!! throw a shift kit in it and check the accumulator piston for the front band. It is ceramic and can break leaving you without 1low, I got an aluminum replacement for mine from AA beep beep mco AMCO
 
Doesnt mean its a 475. My 400 is stamped HD, just has a thicker housing and a bolt on flywheel inspection cover, instead of the sheetmetal one with a couple screws.
 
k20 said:
Doesnt mean its a 475. My 400 is stamped HD, just has a thicker housing and a bolt on flywheel inspection cover, instead of the sheetmetal one with a couple screws.


X2.
 
Isnt the only differance between a 400 and 475 the way the gears are cut? ones helical and ones straight right?
 
here's what I'm going by....
tannyID.jpg
 
And htat says nothin as to the stamping on the case... The stamp (more appropriatley, a cast) means nothing more than thick case/ bolt on cover and i belive only in 4wd's.

If what you are saying is true every 4x4 truck made with a 400 would really be a 475... this is NOT the case...
 
85-m1028 said:
actualy I think a case stamped with K is just the standard 4wd, all 4wd cases came a bolt on inspection cover...
along with an hd:rolleyes:

as far as ive ever seen there is no way to tell a 400 from 475 from CASE alone
 
Besides that page shows nothin about an HD cast into the bell...unless its written in invisible ink:rolleyes:
 
AFAIK, they made a standard case, a "K" case and a "HD" case. both the k and HD case have a bolt on inspection cover. i have seen both in 2wd and 4wd vehicles. not sure exactly what the difference is. i have a 79 motorhome with the th400 HD case.

IIRC, the only difference between the th375 th400 and th475 is the rear output shaft and yoke size.
 
Top Bottom