Prerunner Tech

Explorer Prerunner Rear Gear Swap

When making a prerunner out of a 2WD vehicle you are at a disadvantage. When you buy a 4WD truck or SUV the factory knows the intended use and puts lower gears in the rear-end to compensate for larger off-road tires. This was not the case for our 2WD Explorer prerunner project.

While doing the build of the front and rear suspension, we glanced at the pumpkin on the rear-end and saw the dreaded numbers 3.27.

I got a taste of these hi-way friendly gears on my trip over to the painters to get the front ‘glass and hood painted. I could barely get out of 3rd gear on the freeway.

Knowing we needed to re-gear our Explorer prerunner, we gave a call to Dan’s Driveline Repair. We spoke with Daniel one of their Techs about our options.

Using a guide that told us what our RPM was stock, we could either got with a 4.11 rear gear or a 3.73. Since we do a lot of traveling, covering races and events we decided to go with the more “hi-way” friendly option of the 3.73s.

Daniel got our Explorer up on the lift and quickly went to work.

After placing the catch can under the 3rd member, Daniel loosened the lower bolts of the cover plate to let the oil drain. While the last few drops drained, Daniel Disconnected the driveshaft.

Next he removed the brakes and the c-clips so he could pull the axles out.

Then using a 20 ton press he made easy work of driving the yoke out of the bearings.

We then headed over to the machine shop so and placed the yoke on the lathe to polish it up. The attention to detail is what made our decision to hire Dan’s Driveline so easy.

Next the new gears were installed on the bench.

Now it was time to install everything back in the rear-end. You can see the white grease on the gears. This is used to check the clearances to ensure the gears are properly spaced.

Daniel reinstalled the axles.

When it was time to close up the pumpkin, Daniel noticed the ugly shape our rear-end cover was in. He turned to me and said, “Let’s spray some “New” on this”. Daniel sprayed a nice layer of satin black and our pumpkin looked brand new.

After the install was done we took it for a test drive. What a difference, the pep was back. We also found a speed trap radar near the shop and tested the speedometer and it was dead on, so no wondering how fast you are really going when you pass a cop.


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