Zf 6 speed transmission extension housing gasket and seal

[Rich C.]

Does anyone have a source for these two parts? I located a new extension housing, I THOUGHT THAT WOULD BE THE HARD PART!!! The gasket and seal are both discontinued. I thought I read somewhere that the Turbo 400 trans used the same seal, but has anyone tried one? Apparently I have a crack in the extension housing as I've already replaced the VSS. Thanks

1973 LS-4 454 Coupe owned 24 years
1996 LT-4 CE Coupe owned 9 months (38,000 miles)

[Joe L.]

Re: Zf 6 speed transmission extension housing gasket and seal

Does anyone have a source for these two parts? I located a new extension housing, I THOUGHT THAT WOULD BE THE HARD PART!!! The gasket and seal are both discontinued. I thought I read somewhere that the Turbo 400 trans used the same seal, but has anyone tried one? Apparently I have a crack in the extension housing as I've already replaced the VSS. Thanks

1973 LS-4 454 Coupe owned 24 years
1996 LT-4 CE Coupe owned 9 months (38,000 miles)

Rich-------



The rear seal was GM #10140538 but it is discontinued. However, you can obtain an equivalent Federal-Mogul seal under their part number 4333N.

The extension housing-to-case gasket was GM #12507668 but it's also discontinued. You can obtain an equivalent gasket from White Racing Products (whiteracingproducts.com). I know they sell it as a kit with other parts but you may also be able to get it from them separately. They have the seals, too.

I believe that all these parts are still available from ZF but I don't know how one purchases directly from them. ZF has (or, at least, used to have) a service center somewhere in Illinois, north of Chicago.

[Rich C.]

Re: Zf 6 speed transmission extension housing gasket and seal

Thank you Joe, Rockland Gear handling all the ZF parts. I was able to purchase a new extension housing from them at $367.00! Suppose I'm lucky they still had one! Oh and yes, they still had the gasket and seal as part of a kit for ANOTHER $250. Cried uncle!!! Went all the usual routes, local Chevy dealer did a dealer search...no one! I'll try your suggestions, thanks!!!


1973 LS-4 454 Coupe owned 24 years
1996 LT-4 CE Coupe owned 9 months (38,000 miles)
Victory Hop Devil Ale...currently on tap!

[Joe L.]

Re: Zf 6 speed transmission extension housing gasket and seal

Thank you Joe, Rockland Gear handling all the ZF parts. I was able to purchase a new extension housing from them at $367.00! Suppose I'm lucky they still had one! Oh and yes, they still had the gasket and seal as part of a kit for ANOTHER $250. Cried uncle!!! Went all the usual routes, local Chevy dealer did a dealer search...no one! I'll try your suggestions, thanks!!!


1973 LS-4 454 Coupe owned 24 years
1996 LT-4 CE Coupe owned 9 months (38,000 miles)
Victory Hop Devil Ale...currently on tap!

Rich-------

You got a good deal on the extension housing. It carried a list price of over $700 when it was discontinued by GM.