Five Lug Bolt Pattern Conversion - Hole Exchange

Owning a truck with six-lug hubs and axles used to be a pain when it came time to buy new wheels for your ride. With the exception of billet wheel manufacturers that would custom-make a wheel with the right bolt pattern, which is really expensive, there weren't a lot of choices for rims. Let's face it: It used to be a five-lug world when it came to aftermarket wheels for trucks. In some respects, it still is.

There are many ways to make the switch from six- to five-lug, such as purchasing new axle and hub assemblies from a donor truck or buying aftermarket upgrade parts. However, this can be quite costly. Here's a quick, cheap way to do the job, using the parts you already have. We wanted to run five-lug wheels on our '67 Chevy C10 project truck because we like the look of five-spoke rims, which you can normally only get in a five-lug pattern. We didn't want to spend a fortune to buy new parts, so we just welded up the holes in our existing hubs and brake rotors, then had a machine shop drill a new five-lug bolt pattern in the parts. It was quick, relatively easy, and cost less than 300 dollars. Here's how it all went down.

1. To make the switch, we first pressed out the existing wheel studs in a hydraulic press. The stud's serrated shaft cut into the undersized holes for an interference fit, which is why we needed a press to get them out. We saved the OE studs and reused them later on.	2. We will be welding up the existing bolt holes, so we had to remove the paint and corrosion from the hubs and rotors, using a die grinder and a Roloc sanding wheel attachment.	3a. Next, we TIG-welded the holes, starting at the bottom of the hole and working out way upward, until the weld was above the flat surface of the part (3a-3b). The heat generated by this procedure is excessive, and it will warp the part, so be prepared to re-machine the face of not only the hubs but the rotors, as well, to make them flat again.
3b. Next, we TIG-welded the holes, starting at the bottom of the hole and working out way upward, until the weld was above the flat surface of the part (3a-3b). The heat generated by this procedure is excessive, and it will warp the part, so be prepared to re-machine the face of not only the hubs but the rotors, as well, to make them flat again.	4. Once the welds cooled off, we sanded them down as close to flush with the surface of the part as we could. We fly-cut them in a mill later on to make the parts perfectly flat again.	5. When it's time to drill the new pattern, it's best to leave it up to a good machinist who owns either a CNC mill or at least a manual mill with a rotary table. This will ensure the best shot at getting the pattern correct. Also, remember to position the new pattern to avoid drilling through the old holes. The weld is extremely hard, and drilling through it will damage that expensive drill bit.
6. Here's what it looks like when you hit the pre-existing hole that was welded up. Notice the hole in the side wall where the weld didn't completely fill the hole.	7. Once the new five-lug pattern was drilled, we machined the lip off of the brake rotors to allow our aftermarket Boyd's billet rims to fit onto the Ford Expedition rotors. This also worked to square the mounting flange of the rotors after the welding heat had warped them. The old bolt pattern is barely visible, and we now have five-lug parts for less than the cost of a new set of high-performance rotors.