Horsepower is good. So is torque.
But it’s not always about how much power your vehicle makes. Performance can also come down to how you apply that power. That’s why street performance, race, and truck enthusiasts sometimes turn to ring and pinion gear swaps to optimize the way horsepower is transferred to the pavement.
By going to higher or lower gears, you can improve acceleration, enhance cruising or highway performance, and even achieve better fuel economy. It really comes down to your vehicle and its intended purpose. You can learn more about matching gear ratio to your vehicle in this video post or this earlier story on choosing the right ring and pinion.
So how complicated is a gear swap, you ask?
In this exclusive video below, Motive Gear’s Eric and Jeff take you step by step through a ring and pinion installation. In this particular case, they are going from a drag car-oriented 4.30 ratio to a slightly milder 4.10 in a Ford 8.8 rear-end. However, almost all of the information will apply to a ring and pinion install on a Chevy or Mopar as well.
The Motive Gear guys walk us through the entire process using Motive Gear’s Master Ring and Pinion Installation Kits. They will tell you what tools you need. (A dial indicator to check back lash, calipers to inspect shim thickness, and a good torque wrench.) Then the guys will go through the checklist and show you how to do each of the following:
- Dressing the gear (eliminating imperfections and burrs)
- Attaching the ring gear to the spool
- Setting up the pinion
- Inspect the housing
- Replacing the bearings
- Temporary pinion installation minus the crush sleeve and pinion seal to make simple depth changes
- Taking all play out of the preload
- Installing the carrier and running the pattern
- Using a rubber mallet or brass punch to seat the carrier
- Installation of carrier bearing caps
- How to check backlash and increase or decrease if necessary (recommended backlash is 0.008-0.010”)
- How to pull the carrier out and prepare for final assembly
The video is just over 13 minutes and will provide value to any technician or backyard mechanic looking to add new torque-generating gearing to their race car, truck or street machine.
Check it out here:
Great video, I’m currently putting a motive gear 3.7 into my Aussie Ford 7.75″ diff. Did you not need to use a diff spreader? Finding a reasonably priced one is whats holding me up but this video gives me hope.
I notice on the 2008 f150 8.8 kit the front pinion bearing is alittle smaller than the original so when I put the yoke on its getting to tight to turn and its not even crushing the sheelve yet… do I make up for the thickest on the bottom bearing by adding a shim to the shock shim or can I put the shim behind the oil shim near the yoke… and can I use a solid washer instead of a crush washer on a stock pinion