Tools required for the job: Knee Pads
When the boss has to stand on the brakes to get his truck to stop, and the truck is growling from the hidden grotto inside the hubs, who are you going to call? Master Mechanic Dave and Learning Lolo!
This week’s mechanic lesson was to replace the front and rear hub assemblies on Martyn’s Ford 250. As fate would have it, the original hubs of a F-250 have a limited life span. With that said, Martyn’s hubs ruled the road from 2001 until yesterday. These hubs were driven straight to the scrap metal pile, where they were laid to rest in pieces with a respectable 228,000 miles tacked on them.
Some still consider the 7.3L Power Stroke to be Ford’s best diesel engine. Martyn loves this truck so much that he said, “If you want to keep this truck, all you have to do is maintain it, and it will run forever. It is the most reliable vehicle I have owned.”
Now, I have assembled and disassembled hubs before, but not on a vehicle. The hubs I am most familiar with are the electric braked hubs we put on the Adventure Trailers. The electric braked hubs have a race, a separate inner and outer bearing, and are adjustable.
I noticed that Martyn’s rear hubs looked similar to our electric brakes because of their drum-like appearance. Even though it appeared that way, I quickly learned the hubs on the Ford were a disc based system. Dave explained to me how the Ford’s hub bearings are a sealed unit, meaning there can be no adjusting or maintenance performed on either side. Dave also informed me that the bearings in the rear hubs are located in the axle and slide into the rear differential. I was finally starting to get my “bearings” on the whole concept of hubs!
I take safety rather serious at the shop. With that said, we brought the truck into the shop, jacked it up, and put jack stands underneath as a safety precaution. I decided to start on the front passenger side of the truck by taking off the hub cap with a flathead screwdriver, first. Following that, I removed the lug nuts with an impact in order to dismount the tire and wheel.
Next, I took off the two bolts that held the brake caliper, coupled by the two bolts that held the brake caliper bracket. The bolts were rusted on, so Dave showed me that I can hit a wrench with a rubber mallet to compensate for lack of leverage.
Promptly after, I removed the disk, rotor, brake pads, clips, and springs.
Next, I took off a “C” clip using pliers, which allowed me to take off the four-wheel locking hub assembly and get to the snap ring that was holding the washers to the hub assembly in place.
Once I unbolted the ABS wire and detached it from the wiring harness and removed the four bolts that held the assembly in place, I was finally able to remove the entire unit.
I applied some Loctite on the new studs and screwed them into the new assembly, turning them with a ratchet and socket to make sure they were good and tight.
From here, I retraced my steps and put the entire unit back together. Dave made sure I didn’t overlook the vital step of constricting the pistons inside the brake caliper. Dave explained that making sure the calipers are clamped down is important in the event that someone pressed the brakes from inside the vehicle, which would ultimately result in the pistons popping completely out of the caliper, compromising their integrity. 10 shop star stickers for Dave for practicing good shop habits!
After all the wheels and tires were mounted and torqued to spec, there was only one more thing to do. What would new hub assemblies be if there wasn’t new brake fluid to go with them? During the process of bleeding the system, it was obvious to see the difference between the new and clear fluid being ejected, versus the old and brown brake fluid.
At the end of the day, it worked out well having Dave guide me through the hub assembly process and helping me identify specific parts on one side of the vehicle, so that when I worked on the opposite side of the vehicle by myself, I was successful. Thanks to Dave’s mechanical skills, I am proud to say that I can now assemble and disassemble hubs on a Ford 250 and identify some vehicle anatomy that I couldn’t before. Initially, I wasn’t overly stoked about being hunched over in a wheel well with an axle threatening to jab me in the gut with its grease, but I got the hang of it thanks to Dave’s teachings, my own experience, and a little bit of muscle memory. This process wasn’t as hard as I imagined it would be, and when the job and teaching moments were complete, it only took about four hours. Now the shiniest parts on Martyn’s truck are it’s hubs! So, if you or someone you know needs new hub assemblies on a F-250, who are you going to call?
Written by Lauren “Lolo” Sherwood
Photos by David “Dav” Argust