Rear differential suggestions

[1project2many]

You've probably already realized there are a *lot* of excellent builds and very talented people on this forum that are willing to help out. It looks like your questions have changed from advice about the rear axle ratio to advice about a direction to go with your project? I'm usually in the minority here because I prefer a more practical and less expensive approach to building a good truck but I'll share my perspective.

Truck projects can take much longer than expected. Mine was already on the road and running when I started the body work. Three years passed before it drove out of the shop. For cost and simplicity I left mine mostly stock. It still has drum brakes, still has the stock rear axle and transmission, no air conditioning, and the original manual steering as well. I even left the same brake shoes and shock absorbers on the truck that were there when I bought it. Most of the folks on this forum wouldn't keep their truck at this basic level but I've been using mine since '98 and enjoying it the whole time. And despite what I seem to see on the forum most of the parts on the truck are capable of surviving well in daily use.

With your truck already painted it would seem like any changes or upgrades should be planned so bodywork and paint isn't touched. I don't disagree with the safety concerns over the original single chamber brake system. The master cylinder is underneath the floor of the truck and there are kits available to put a modern dual master cylinder with brake booster under the floor. The original brakes do require some effort to use and if you mostly drive a vehicle with power brakes the manual system will seem like it's fighting you as your driving day gets longer. If you replace the drums with discs you're probably heading for a replacement master anyway to make the brake balance work out. I'm happy with the drums on mine but I am going to add a '60s vintage brake booster in order to get power assist.
Edit: The early Chevy vans also used beam style axles. This disc brake swap seems well documented by someone with good experience: http://www.angelfire.com/wv/joyrde/v...scBrakes1.html


The factory steering parts were designed to work with skinny, stiff, bias ply tires. Switching to modern radials requires a lot more force applied through the components and you may find driving to be tougher than expected. My truck didn't seem tough to drive when I was in Montana where we had wide roads and little traffic. But back east people drive very agressively. Stop lights here are sometimes only a couple hundred feet apart and there are plenty of folks racing to be the first person to stop at the next light. Plus many of the roads here are in pretty rough shape. Driving with these folks is a bit more challenging. Since I'm not getting any younger so I have plans to improve the steering components and possibly to add power steering to the old solid axle. Like your truck, the body work on mine is done so any changes I make will not involve redoing the body.

An automatic transmission is a great idea. And I agree that keeping a shifter out of the center of the truck makes riding with a child in the center much easier. '55-'59 GMC and Chevy trucks came with automatic transmissions so there are column shifters that bolted directly to the original column. They are likely to be tough to find and expensive but I wonder if it would be relatively easy for a creative person to build something similar or to modify a 3 speed shifter for the original column. Most folks end up adapting a later column instead of working with the original part. Since the original box and column don't easily separate the original column and the steering shaft will need to be cut and and modified to connect with the later column. Many folks seem to buy a column from a RWD car but I wonder if a later FWD column might be a good choice. The FWD columns are shorter which might allow the original column to be cut inside the cab of the truck. The FWD car columns also use a cable between the transmission and column which might be easier to adapt to the automatic than building linkage.

My real lament is that there's no room in the cab of the truck. For years it was only my wife and myself and we could bring a small cooler and a bag when we went on long trips. Once my son came around it was much tougher. And with two kids there's no way everyone can go out for a drive. If you are looking at making any changes inside the cab I'd recommend trying to incorporate more storage space.

Good luck!