AllC34Me

Does anyone here know when changes were made to the removable cross member of automatic cars to remove the front lower mounting tabs? I ask because my 1969, 71, and 72's all have the front tabs but I have a cross member that does not have the tabs that I discovered only after installing it and trying to mount it up.

Big Eddie is selling his cross member here on the forum and his picture shows his 1980 removable cross member and it does not have the front tabs, so I know that it must have been sometime between 1972 and 1980.

If you know could you share that with me please? Trying to figure out if I use this one or try to find another replacement for my 1972 racer project.

How did they secure the transmission after those tabs were removed?

Sorry to ask you all, just confusing me and I would like to sort it out.

Thanks for your consideration and help.

Best regards,

David

JimLentz

David,

I can't picture the tabs in my mind. Do you have pictures of these tabs.

MelWff

The Corvette Parts and Illustration Catalog from December 1983 shows only one automatic transmission crossmember used 1968 to 1979 part number 12300911. 1980 and up use 475334.

tracdogg2

1976.
The tabs are for th350 trans. 400 trans doesn't use the tabs.
Mike

AllC34Me

Jim,

Front tabs are shown in this picture. Hope it is large enough to see.
The transmission mounting plate mount here.


Mystery not yet solved.

David

AllC34Me

1969 and 1971 manual frames cross members both have the tabs.
So manual transmissions needed the tabs?
David

AllC34Me

I posted a picture Jim, hope it helps.

AllC34Me

I can now confirm that my 1971 automatic with TH350 does not have the tabs on the front of the transmission.

I cannot be the only guy here that has had this issue when using a automatic frame with a manual transmission...can I?

tracdogg2

71's didn't come with 350 trans, only 400's. TH350 didn't come out until 1976. All standards had the tabs 63-79. 80-82 is a completely different cross member.

JimLentz

I checked my '77 earler that came with a TH350 and I couldn't find any tabs. However, I just looked at the AIM and the frame picture shows the tabs, how odd. Perhaps at one point my crossmember was replaced. I looked further and it shows the crossmember for the TH350 has the tabs and the bracket bolts to it, so I think I have the tabs, but they are hidden from my view by the bracket. The crossmember for the manual transmission does not show the tabs because it doesn't require that bracket.

tracdogg2

The 3 speed and 4 speed manual transmissions 63-79 cross members have the tabs and use the mount bracket. Only the 400 does not use the bracket, the trans mount sits on top of the cross member.

AllC34Me

Yes sir, correct, I have a Th400 in my 1971 auto car. Sorry about the earlier error.
David

AllC34Me

So here is the real question. I am using a TKO-600 five speed transmission on an automatic frame. Cross member does not have the tabs to mount to. Do I need to find another cross member that has the tabs or modify this one to add the tabs? Sure wish I had caught this before putting my transmission back on the chassis. Glad I found it before the body went back on though. Easily removed, on my lift now.

Live and learn.

David

tracdogg2

Build the cross member you have.
Mike

68/70Vette

I have a new iPhone 6+ and still don't know how to use it. I had my transmission crossmember sectioned. The sectioned crossmember with the tranny attach points can easily be removed and it makes replacing the manual tranny sooooo much easier. The tranny is a TKO600 five speed.

AllC34Me

I'm going to shut this thread down now.
Sorry for any inconvenience.
Best regards,
David