Here's another 55 Buick Roadmaster question on replacing torque tube rear end to open drive line. I have a 66 Buick Electra that I bought for the 401 Nailhead and ST400 transmission that I plan on swapping into the 55. Can the rear end be used on the 55 from the Electra? I know I've read of folks using a whole bunch of different rear ends like Ford 9 inch. Just figured since I already have this one in Electra I might as well use it if it works as far as same width of the stock 55 rear end. What say you?
Well, if the width is ‘close enough’, it would make perfect sense to use the same rear end that Buick engineers paired with the engine/trans. The ‘fly in the ointment’ with Buicks is adapting an adequate rear suspension control system in the absence of the torque tube. There are several methods that will solve the problem, but all will require some effort and careful execution. If the width of the ‘66 rear end is ‘close enough’, study the control arms and frame bracket setup of the Electra and do some measuring/comparing with the ‘55 ch***is. A long time friend of mine, who is an excellent fabricator, adapted the axle and control arm system from a ‘70 Monte Carlo into his ‘38 Buick 2 dr sedan and it not only looked ‘factory ‘, it sort of was. Your ‘55 ch***is is really quite similar to the ‘38 and the ‘66 Electra rear suspension is, as I recall, similar to the Monte Carlo control arm system. Another method would be to use an aftermarket parallel 4 bar system. It requires a Panhard bar for lateral control of the axle but your ‘55 also does and already has that in place. Time to dive under both cars with tape measure, camera and note paper/pencil!
I appreciate the response, yes that's my way of thinking as well since the engine/transmission and rear end all are coming from the same vehicle why not just go ahead and use the same rear end when I do the swap. I did take into consideration the need for something like a 4 link set up which I plan on getting done as well. I haven't had the time to check first-hand the measurements of the width of the axle...but from a quick search online I came across an article where someone did a swap using a Ford 9 inch 58' from flange to flange and it worked great... another search for the width on a 66 Electra rear end was also 58' flange to flange so with that being said it all "should" work just fine.
Guys will do just what @Hnstray sugested. Some guys using the parallel bars off late 60’s early 70’s Chevy pick up trucks also. Another suggestion is a jag rear out of a series 2 or 3 car. Cheap, perfect width and real easy to adapt. Was a thought when I owned my 55 Buick. Sold it before I did anything to it except drive it with it’s leaky trans ! Lol!
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