Technical Buick Guys- I have a question

My son has a 48 Buick that is all apart and all stock (no engine). What are my options for the rear end? We want to update/upgrade the drive train to an open system with an automatic. The original frame and suspension has been restored. I'm wanting to either replace the whole rear end or replace the third member with an open one. The first option, I'm wondering if a rear end out of a '60's Chevy pickup would work. They seem to have similar rear suspension styles, but I don't know about the width of the trailing arm spacing between the two and am hoping someone out there can offer some insight. The second option is just bolting in a new third member if there is an open one that would bolt right in. Here again, I'm looking for some real word experience or insights as to what would bolt in and work with the original axles.
r

 

I doubt that there is an open chuck that you can bolt in there and if there was it probably would not take the punishment that Wild Willie II is going to hand out.

The C10 rear may be a little bit wide, I would think that if you want to go the truck route a mod '50s truck would work. That is going to land you with 6 lug wheels. Is the old buick 6 lug? I am not down there but the schoolster would probably throw a tape on one our C-10s if you like.

 

Have him measure one back plate to back plate and then from trailing arm mount to trailing arm mount. That should get me the info I need. The Buick's drums are 5-bolt.
r

 

Well we can change the bolt pattern no problem first we figure what front brakes you are going to use we got 6 bolt wheels to use in the mean time. I'll be chatting with Phil this evening or tomorrow I'll get him to throw a tape on the Pusher.

In the meantime maybe someone knows that answer for the raven.

 

What is the model? 40 or is it a 50/70. Difference in size between the smaller specials (40's) and the larger 50/70's

 

I would use the 60-72 truck setup. Another approach is a 1950 Olds 98 trailing arm suspension. It might be just right as far as track width. Either way, this is probably the simplest method.

 

I'm running a Gambino 4 link and 72 c10 12 bolt rear in my 54 Buick. It is a little wide as others have said. I had to get some rear wheels made with more offset. 15x6 with 3.5 backspacing. Even with those wheels it's tight to get around the factory half skirts, so I installed airride in the rear to make it easier to get the wheels off. Idealy I would have found a nine inch out of an Edsel. They have the correct width and are still 5x5 bolt pattern.

 

Allow me a couple of comments here. A Buick third member through '55 with bolt into your axle housing. ratios in the range of 3.36 are available. HOWEVER, the issue of controlling the axles gyrations have to be dealt with. Just like on torque tube Fords, the diagonal braces are not up to the task of taking the loads coming their way now that the torque tube is gone.
GM pickup "truck arms" or the aforementioned early '50s Olds setup are two good, and relatively simple, options, but not the only ones out there.

As for wheel bolt pattern, those Buicks are 5 on 5" bolt pattern. There are a variety of Buicks Olds and Pontiac....as well as Chevy/GMC pickups, later Chevrolet, Olds and Buick full size cars and some big Ford, Mercury and Edsel 9" rears that share that pattern as mentioned in the above post.

I have two Edsel and a '57 Merc rear axles for that very reason. One of which is going into my '38 Buick Coupe shortly.

Ray

 

Huh, I figured the original trailing arms would be fine with an open drive line. The mounting pads on the rear housing mount just like the 60's Chevy trucks' trailing arm setup.
Thanks for the info about the third member, Ray. That's the kind of into I was looking for. So, i guess, I'm going to have to take the body off the frame again to get the rear suspension where it needs to be.
r

 

Chev Caprice station wagons use the 5" 5 bolt wheel, like Chev 1/2 ton pickups and vans.

Could you adapt the Caprice wagon coil springs and 4 links to your frame? It should be ideal, engineered by GM for a car of similar size, weight and power.

 

What year?
r

 

Check out your favorite junk yard for Caprice wagons, big Buick wagons and possibly rear drive Buick, Olds and Cadillac sedans. Look for coil spring suspension. Measure the track width and the wheel bolt pattern.See if you can find a close match to your car. If you find something suitable, see if you can buy the whole rear half of the frame with rear suspension.

When you get it home, start measuring your old frame and figure out how to adapt the rear axle and suspension to your old chassis.

If you have never done this before, this is a hell of a place to learn how to fabricate and adapt stuff. Better take it to someone who knows what they are doing. Keep death off the roads.

 

Done it before, not my first rodeo. Thanks.
r

 

So, I am assuming that it is a 50 or a70. 89 Caprice rear will slide right in. Correct width and 5 on 5 so stock wheels can be used. Many of those Caprice's were police cars so they have a strong 3rd member and good gears. Take the trailing arms when you buy the rear and the front mounts for the arms. You can use the stock Buick hook up on the Caprice axles with a spacer that you can make by cutting a 4" piece off an end of a pipe and welding to your axle housing. Graft the Caprice trailing arms to the front end of the original Buick arms and fasten them to the Frame. It is kind of like splitting a wishbone. You can lower the car with a set of 79 El Camino springs.