Removable Transmission Crossmember
Thread Starter
Racer
Joined: Aug 2006
Posts: 290
Likes: 0
From: Saskatoon Saskatchewan
Removable Transmission Crossmember
Can anyone give me detailed information on the hole sizes and locations on a '73 chassis for a factory removable crossmember? I am going to be cutting my welded one out and would like to put the factor holes in for a new one. I will be making my own crossmember but I want to have factory mounting in case I ever want to switch to a factory one. And dimensions or drawings are appreciated.
T
T
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
This is SO simple it's a joke, and been in my car for over 6 years now on a DD basis...
cut the cross member about 4-5" inboard of the rails, weld ~1.5" angle iron to the top rear sections on the removable unit, on the bottom you weld slightly smaller angle on the backside, that grabs the welded ends on the frame just fine, so to put a fore/aft 1/2" bolt to secure it into place.....
NOW as a later mod, I cut out the bottom of the exhaust loops, and cut the support back at a angle through the square lateral section, boxes it in with a vertical section to the top of the OEM loop....
and I can literally drop my entire exhause out with.....
DIG THIS......
6 bolts, and outta there, whole thing from tip to engine OUTTA there....seriously....
then...just ~6 more bolts and the cross support is on the ground, and then I can drop the trans clean without effort....
GOD I"m lazy......
cut the cross member about 4-5" inboard of the rails, weld ~1.5" angle iron to the top rear sections on the removable unit, on the bottom you weld slightly smaller angle on the backside, that grabs the welded ends on the frame just fine, so to put a fore/aft 1/2" bolt to secure it into place.....
NOW as a later mod, I cut out the bottom of the exhaust loops, and cut the support back at a angle through the square lateral section, boxes it in with a vertical section to the top of the OEM loop....
and I can literally drop my entire exhause out with.....
DIG THIS......
6 bolts, and outta there, whole thing from tip to engine OUTTA there....seriously....
then...just ~6 more bolts and the cross support is on the ground, and then I can drop the trans clean without effort....
GOD I"m lazy......
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,333
From: North of Toronto - Ontario
This is from a 72
There is a round hole in the frame slightly forward of the mount
Measuring from the center of that hole back to the first bolt
4-7/8" (burned an inch on the tape)
The two bolts on the cross member are 4-5/8 apart (did not burn)
The bolts are 7/8 in from the edge of the frame overlap
There are another set of flanges with an engine-mount bolt through them but I can't measure anything on those
Just see them in the background here
HIH
Mooser
There is a round hole in the frame slightly forward of the mount
Measuring from the center of that hole back to the first bolt
4-7/8" (burned an inch on the tape)
The two bolts on the cross member are 4-5/8 apart (did not burn)
The bolts are 7/8 in from the edge of the frame overlap
There are another set of flanges with an engine-mount bolt through them but I can't measure anything on those
Just see them in the background here
HIH
Mooser
Le Mans Master
Joined: Dec 2003
Posts: 5,380
Likes: 415
From: N J
Heres what me and my friend did to mine. Do 1 side at a time and it stays excatly in the same position. Two 1/8 inch plates welded in on each side and then bolt them. More bolts in the front not seen in pic. Its solid.
Thread Starter
Racer
Joined: Aug 2006
Posts: 290
Likes: 0
From: Saskatoon Saskatchewan
Thanks for all the responses. Mooser that info is great for a stater. I am going to see if I can find a stock transmission crossmember to borrow to mock up the holes from around here. In the mean time does anyone have their body off and could fill in some blanks if I supply a drawing? I still want to put the stock mounting positions on my frame. I know there are 1000 ways to make the crossmember removable, but I like the idea of being able to go back to stock if I want.
Thanks
T
Thanks
T
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Joined: Jun 2000
Posts: 38,923
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From: Southbound
Cruise-In II Veteran
Not in the AIM because two different frames were supplied by A. O. Smith; one for standard tranny cars and one for AT cars. The AIM shows only bolting in the x-member for the AT frames since that was done on the frame line; the holes were already in the frame.