For the back story, my dad bought a 54 Chevrolet 3100 back in the mid 60s. I have owned it since the late 70s. I finally got to the point in life that I tore it down for some major refurbishment. He also at that time put a set of vintage E-T torquethrust wheels on it using 6 bolt to 5 bolt adapter plates. I know they are not correct to the truck but they are all I have ever known it to have so they are correct to me. I always hated the adapter plates. They resulted in bad suspension geometry and I always thought they were unsafe as they had screw in studs that tended to work their way out over time. Part of the upgrade was to do 5 bolt "the right way". The fronts were easy. Car front drums from the same year. The rears not as easy. Moser Engineering said they could weld and re-drill the flanges for the new bolt pattern. That is until I sent the axles to them. As it turns out, time is no friend as when they weld up the flanges, they are too hard to re-drill. They cannot make new axles as the bearing surface is too large for their equipment. They say someone with an end mill may be able to do it. I am no machinist so I don't fully understand the obstacles. What their suggestion is is to cut the rear end housing ends off and weld on later ends to get a different size bearing and the bolt in style axles vs. the C clip retained design. At that point, they could make me a set of axles to fit. Essentially, the $90 drill job just turned into a $700+ ordeal. I foresee problems with backing plates, brake design change, e-brake cable issues, and more, Has anyone gone through this or have advice/suggestions? I want to retain the torque tube design as it is a hydra-matic truck so a later rear end as a whole is out of the question I think. Is there a set of axles that would be the correct length and spline to work with the old rear end components with the new axle ends and the 5 bolt wheel pattern? That could save the custom axle part of the project. Looking for advice or past experience. Thanks, G.H.
Swap rear ends. It's done all the time. Measure your width drum to drum, refer to this: http://www.jalopyjournal.com/forum/threads/helpful-rear-axle-width-chart.108428/ Find rear end that matches and install. There is no cheap method that is good. You will have to modify axle brackets and mounts, probably the end of the driveshaft and or U joint, brake lines, parking brake. Maybe some new lug nuts. The flipside to this if that truck has been running adapters for 50 years without a problem, I can't imagine a failure occurring at this point. A wheel adapter on the rears with good studs and proper torque is no big deal. The rim does not know it has an adapter bolted to it. It just thinks it has a different backspace.
Simple procedure for a good machine shop Yes the holes that get welded are hard to cut wit a normal drill , you will need to make the holes with a carbide end mill and/or drill ... You may also need to turn down the hub witness to accept your wheel
I have punched right through many an axle flange with the very same Cobalt drill bit. Still going strong. Any competent machine shop should be able to re-drill. A qualified welder should be able to take care of the holes. I cannot believe that we are even having this discussion.
Pattern change, 5-to-4, using a @rottenleonard drill guide (custom made, on request), with Cobalt drill bits, on a my Milwaukee hand drill. This axle had solid flanges, so no welding was required. Even so, I am not sure what "too hard to drill" is.
6 to 5 ..filling old holes welding the axle flange makes the weld and the hole harder than surrounding area a normal drill will want to walk and dull , carbide cuts through and doesn't move I've tried tig , mig and burying in sand same thing has happend to me on some old ford forgings also
If you preheat the flange to about 450* before welding it will prevent the hardening. When you weld with the flange cold, the m*** of the metal around the weld pulls the heat away fast enough to cause the hardening since the axle is a medium carbon steel. Once the weld is done, its too late to do anything about it as the hardening happens pretty much instantly as the welding goes on. Preheating reduces the ability of the surrounding metal to absorb additional heat, so the cooling at the weld area happens too slowly to allow the steel to harden. Heating the flange to 450* won't affect the hardness or strength of the flange as the initial heat treatment would include a temper cycle at a substantially higher temperature to temper the material back into the range where it will be tough. Once its welded cold and hardened, it would require heating to around 1500* to anneal the hardened area.
The Jalopy Journal
