88 C4 Leaking Tranny - Rear Yoke?

I've brought my car back to a reputable tranny shop twice now to seal tranny
leaks. Finally stopped leaking except in the rear. Tranny guy tells me
that the rear trasmission seal is leaking and that he has to replace the
whole rear yoke assembly? Replacing the seal didn't stop it. Does this
make sence? is this a common prob with turbo 700r trans..? I don't think
he's charging me for the labor to tear it down again but he's talking
between $250 - $800. for a used/new yoke assembly?

Sorry about the flood of posts. I haven't been on here in awhile. Didn't
use my vette for a few years due to financial constraints.

I used to get great advise from this group back in the day. Hoping someone
will take the time to respond

Cheers!

"88C4RagTop" wrote in message

> I've brought my car back to a reputable tranny shop twice now to
> seal tranny leaks. Finally stopped leaking except in the rear.
> Tranny guy tells me that the rear trasmission seal is leaking and
> that he has to replace the whole rear yoke assembly? Replacing the
> seal didn't stop it. Does this make sence? is this a common prob
> with turbo 700r trans..? I don't think he's charging me for the
> labor to tear it down again but he's talking between $250 - $800.
> for a used/new yoke assembly?
>
> Sorry about the flood of posts. I haven't been on here in awhile.
> Didn't use my vette for a few years due to financial constraints.
>
> I used to get great advise from this group back in the day. Hoping
> someone will take the time to respond
>
> Cheers!
There is only 2 things that allow a seal to leak, the seal its self
and the surface it is sealing on. If you have been around the Corvette
groups very long you have seen the problems with brake seals, same
problem. Rust. The yoke is cast iron and is polished by the seal when
driven. Since it works in and out as well as around it can be left set
with bright polished cast iron exposed to allow rust to form. Next
time you drive it the rust becomes a rasp and eats your seal leaving
some rust in the seal to eat the yoke. At some point even a new seal
will not seal a yoke with a ring cut in it from the previous seals.
Some repair shops have the ability to sleeve the yoke, most don't
and/or choose to replace it; but either way it needs to have a good
sealing surface. Is it common? Yes, for cars that sit for long periods
of time regardless of the transmission type. As for the brake seals
they just trap the moisture under the seal a eat the sealing surface.
Very good reason to flush the brake system as required for its type of
use.

As far as you injector problems, when were the cleaned last?

--
Dad
05 C6 Silver/Red 6spd Z51
72 Shark Black/Black/4spd
64 Red/red/white top/4spd