How hard is it to replace the tailshaft housing a piece a the bottom broke off when i was trying to pull the seal out can that even come apart or do i have to replace the whole transmission i have a spare 700r4 sitting in the back with a good tail housing

 

its held on by 4 bolts. not a problem. obviously you have to take the torque arm off, remove the speed sensor, ect.

 

Ok good know i dont have to remove a tranmission an put a new one im gonna pull the one off of my extra one get started on it tomorrow

 

i need to know how long the tail housing is on a 86 camaro with the 305/700r4??
is it 6" or 9"?

 

There is only one length for the T700 housings but the style varies depending upon what car it is intended for
Corvette shown on left , reg car/ truck on right
F-Body is different again ; has the mount for the torque arm

 

Don't mean to hijack this old thread, but I have a C4 trans that I'd like to use in my 92, can I just swap the tailshaft housing, and throw it in? It looks slightly shorter than the standard 2wd housing, does that not matter?

Thanks, Ken.

 

The output shaft is shorter since the IRS means the driveshaft doesn't push the slip yoke in & out. So you have to get the slip-yoke length 100% correct for proper spline & bushing engagement. What should be done is change the output shaft so it's correct.

 

Thanks for the reply!

From what I've gathered the C4 trans is 29 7/8" and the camaro is 30 3/4", I know you said to be correct I should have the output shaft swapped, but in the interest of being cheap, do you think .950 of an inch is enough to warrant tearing 2 transmissions down? I'm planning to yank my TBI 305 auto and swap in a carb'd LT1 with a C4 trans at the same time, but now I may swap the trans first to see if it will work as is...

 

You'd want to make sure the slip yoke is 100% into the bushing at all times; you want as much spline engagement is possible without anything bottoming out (splines; yoke ears; end of the output; front end of the slip yoke section) and those items need assured for all suspension travel. Basically, jackstand the car, pull shocks and springs and run it through full droop and full compression. If everything checks out, you're good.

A third gen doesn't have enormous rear suspension travel; it's do-able. I don't have a PN or nos. for you however.

 

I'll check it out. I stopped by my garage on my way to work today and the output shaft looks to be similar in length. I have a standard 700 out of a 91 Caprice and the 700 out of the 90 C4 laying next to each other, and while the housings are obviously different lengths, the output shaft sticks out about a 1/2" on the Caprice unit and about a little more than an inch on the C4 unit. I'm gonna pull the housings off and measure the output shaft length when I get some time.

Thanks, Ken.

 

Pics of the trannys.

 

I assume you've torque arm attachment figured out?

 

Where is the trans mount on a 3rd Gen ; is it on the tail shaft housing the same as the Caprice trans shown ?

 

Y-body: no mount provision on case nor tailhousing; drivetrain torque arm bolts to it which eliminates the mount.

All other passenger cars & trucks have a cast in provision behind the pan for a mount.

F-body tailhousing has torque arm provision.

B/D-body tailhousing has mount provision

Trucks have neither.

If someone does want to trade me a Caprice tailhousing for a third gen tailhousing, I do have a third gen tailhousing available.

 

I'm going to use the housing from my 3rd gen. I just used those pics because that's what I had laying around in my garage.

 

Sorry to pull up old thread but if using the C4 tranny in an older car (Vette) with IRS a housing swap to Gen III tail housing could be controlled with drive shaft length since the trans and rear end chunk are fixed?

 

Sorry, I don't really understand your question. What do you mean by gen 3? The ls1 cars use a torque tube to connect the engine to the trans/rearend.

 

I should have said Third Gen, F-Body from the late 80's I guess. A 700r4 tail housing with two mounting holes on the bottom of the tail housing. The 91 Vette my 700r4 came out of had a c shaped channel that attached to rear of the tranny to the rear end. I was searching to see if swapping the tail housing for one with mounting bolts would work in my 80 Vette and came across this thread.

 

I took this to mean that your car's rear end has travel up and down but the Vette trans tail housing could be shorter because the rear end chunk is fixed (IRS) with no in and out movement. Hopefully meaning a swap of the tail housing should still work because my rear end in my 80 Vette is also fixed.

 

I wasn't aware the c3's had an IRS rear. Does the trans use a traditionalmount or is it like the c4 with that C-bar? You could try the c4 driveshaft, but just guessing there, you will probably need a custom made driveshaft.

 

The drive shaft will have to shortened by about three inches for sure unless I can luck up and find a 1982 drive shaft. 82 was the first and only year C3 that got a 700r4 (these had a more traditional trans mount as opposed to the C4's)

TH350's in C3's mount with a standard mount just in front of the tail housing to a crossmember. My crossmember will have to be moved and or modified too but without a place to bolt it to I'm kind of stuck without a starting point. This all started a simple (he he) carb to TPI swap and I ran across a 91 Vette engine/ trans combo close by.

Did you ever successfully swap out your tail housing?

 

No, a guy ended up trading me a 2001 Silverado for my 92, I know, crazy right? I did just pick up an 88 firebird, that would be a good candidate, but it's such a basket case I'm probably just going to part it up

 

 

Check if your Vette trans has on the rear of the case behind the pan, a casting with 2 holes for the trans mount; so do / some don't.
If it does ,your trans mount goes there.( most likely how the 82 C3 was done )

If it doesn't, you will have to replace the C4 tail shaft housing with one that has the pad for the trans mount ($50 on that popular auction site )

 

Thanks, that's the one I'm talking about. If I can use that I'm in business!

My tranny does not have the holes behind the pan.

 

As noted ,a genuine Vette case

 

Sorry 1982 corvettes did not have a 700r4 they had 200r4

 

7 years later....

 

and wrong anyway-'82 vette uses 700...

 

 

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