Here's a pic I found on another forum which shows the removeable cross member and support bracket
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
showkey, Is your gearbox mount plate actually connected to your cross member? The pics don't make it obvious. It could just be that 3rd beer I've had.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
Craig, you are right, it is out there in thin air.
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
If I'm correct,,,,,,,, me? it's kinda like why bother installing a cross member?, unless it is doing something we don't see. I would at least weld a matching plate configuration to the new cross member to allow proper connection to the lower gearbox support plate which is seen in the pics.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
Craig, you are right, it is out there in thin air.
Originally Posted by wrenchguy
Why did you install it if it ain't doing anything?
Good observations......... Mock up only there is shim plate between the cross member and the trans mount that is not present in the pictures. After final weld and install the cross member actually provide some support. Part of this thread conversation and debate is wheather all models used a trans cross member?...
The truck operated for 20 plus years in its former life with no trans cross member with no issues. So yes......cross member maybe is a complete waste of time, money and effort. But some models had a support so.........like the prior post stated it’s winter and need a project. There is the issue that some have mentioned with disc brake install stock cross member when present is a problem. The aftermarket cross member resolves that issue. I do NOT expect any real benefit or changes with the new cross member. One possible benefit is .......I might install a small drip tray to catch the small drips from the torque tube.......similar to boats bilge oil catch devices.
Few more pictures with spacer plate and bolts installed. Final weld of the ends and install to come a little later.
Ahhhhhhh, Now I see the support set up. Cool !! Thanks for the clarification. Now I can sleep tonight.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
Interesting discussion. Though I think no group consensus as to what is correct or original was achieved. I know that both of my 50 3600 pickups with SM-420 trans and front torque-tube (enclosed) driveshaft had NO rear trans mount/ crossmember. There is no provision, no lugs, no ears on the SM-420 case for a mount. I thought, maybe mistakenly, that only 3100's with 3-speed had the trans mount. I'm only saying...
The rear transmission mount does not attach to the case, per se.
It attaches to the torque-tube housing on the rear of the SM-420 transmission. That housing is the same for 3100s, 3600, and 3800s, as long as they had a torque-tube-like attachment.
Here is a picture of a finely restored 52 3100 with a SM420 it does have a crossmember and torque tube bell mount.
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
So, what does all this data tell us? I think the trans crossmember mount was a 1/2-ton item only. And maybe someone already stated that and I missed it...
I know there are new things to learn everyday, even about subjects with which we are familiar. I got my first AD truck in 1989 and have read and studied them ever since. But I don't know it all.
My guess is that the transmission crossmember was needed on the 1/2 trucks, due to the strength (or lack of strength) of the 47-53 1/2 ton rear engine frame-crossmember?
