The Stovebolt Site Forums The Shop Area Driveline 1950 Chevy 3100 Rear End Quandary

A little back story here. Bought this truck as is, previous owner had converted it to a v8 and th350 trans, and 8.2-inch 10-bolt rear end. This is where it gets interesting, there are no shocks, just sits under the leaf springs. It has no control arms, the 10 bolt has the 2 bushings on the top for control arms, nothing attached to them.

My question is, anybody ever add this type a rear end to a 1950 truck and suggestions on what would be the best route to go to add upper control arms? Lower control arms? A panhard bar/centering bar bolt on? Rear sway bar? Preferably all bolt ons?

The springs serve as the control arms. Control arms are only needed on coil spring applications. Coils can't prevent the axle from turning under torque.
I don't think you really need them, unless you're going to the drag strip and need to prevent axle wrap from torque reaction when launching. Then you might consider snubber arms extending toward the front.

I agree with Kevin, however having shocks might be nice. But I think there were trucks around this era that didn't have rear shocks.

With all that rear end hardware that close to the frame, shocks aren't going to have much of an effect. You've got virtually no suspension travel unless you do some pretty serious frame modifications over the axle tubes. It looks like your truck was made to look at, not to drive much.
Jerry

dogdaddy - Your axle appears to be out of a mid to late 60's or early 70's GM A-Body passenger car (most likely a Chevelle). A common swap used by many folks. However, the PO didn't do you any favors by using this setup in the manner installed. The springs are too flat, more reminiscent of a TF truck with the axle mounted below the springs, where your original axle would have been mounted above the springs with a much higher arch and significant clearance to the frame allowing axle travel and spring load compression. Looks like they went for the extreme lowered look, but didn't account for actual driveability like Jerry says.

On your 1950 3100 the spring to axle mounting plates would have been mounted below the original axle/spring pack and the "pins" poking out towards the center of your truck as shown would have been the lower shock mount points and pointing to the outside of the truck. Those mount plates look like TF or later truck design with the pin in the center of the plate VS towards the leading edge on original plates.

As far as suggestions go, in a bolt on world I think you replace the springs with the proper arch height (including proper length spring shackles), remount the axle above the spring pack (will require removal and rewelding or replacing of spring pads on the axle tubes to the underside of the tube) and switching the spring pack to axle mount plate with shock mount to below the spring pack. This will allow for restoring the axle travel clearance you need and a way to figure out the readdition of shocks. From your pictures we can't tell if the upper shock mounts are still attached to the frame or not??? They would have been riveted to the frame on the outside face, forward of the axle center line.

One final note/suggestion. For safety's sake, it's recommended that you use new axle mount U-bolt hardware.

Hy dogdaddy, it is difficult to tell for sure from the pictures, but it appears to me that your rear brake line tubing is mounted to a bracket/tab which is attached to the rear axle, your flex brake line continues from there. If that is actually the case, it will be a short time of driving before the metal brake fractures and then no or partial brakes. The rear brake flex line must run from the frame of the truck to a distribution block on the rear axle, this allows for the up and down movement of the rear axle without stressing the solid tubing.

Very good catch 3B!!! I was so focused on his question about the axle/springs/shocks I missed that very bad (unsafe) modification to his brake lines. Definitely an accident waiting to happen!

If you decide to stay with the lowrider look, a few modifications to the rear end housing and the spring mounting plates and U bolts will give you a couple more inches of suspension travel. Then suitable length shock absorbers and mounting hardware for them can be fabricated. However, nothing "bolt-on" is going to work. It will all need to be custom fabricated. Where in "Tennessee" are you located? I'm about 70 miles south of Nashville near I-65. I'd be happy to help you design something that actually works, and won't make you a rolling hazard to everyone else who shares the road with you. Send me a private message if you're interested.
Jerry

Thanks all great feedback back! Unfortunately this is the case when you take on someone else’s project. My thoughts or plan I am thinking is to replace those to location plates on top of the leaf springs with a more flat plate with no shock post on them. Then look at a set of helper airbags that sit on top of the spring plate and attached to the frame to help raise it up a bit so there will be not as much squat. Then I am looking at a bolt on panhard bar bracket from speedway that will attach from the axle housing over to the frame to make sure the axle at least stays centered. Yes this is a project, no I don’t plan on taking it on Hotrod power tour :-) just for tooling around town till I get it more and more road worthy. Brake line is a good catch I will keep diagnosing it to better fix that problem. As always thanks for the great feedback.

Forget the air bags- - - -and the Panhard bar. Just install spring shackles a couple of inches longer. Flatter U bolt plates are a good idea. You can also fabricate a square tubing crossmember behind the axle to serve as an upper mounting point for shock absorbers. Lower shock mounts can be welded to the axle tubes just inboard of the springs, or clamp-on mounts for a Winters or Halibrand quick change rear axle tube for a dirt track car can be fitted to your housing.
Jerry