Before you purchase parts…

Please read this before you buy parts from us.

At West Coast Differentials we have always supported our wholesale customers by not competing with them. We do not sell parts online, and have never gone out of our way to pursue retail sales. Nonetheless, we do sell parts to retail customers on a will call and mail order basis to those that are capable of installing parts themselves.

That brings us to the point of this post…

If you are planning to have a shop install your parts, we strongly recommend that you have the shop / installer purchase the parts.
Here’s why:
  • Most shops will not provide a warranty on parts you buy elsewhere. This creates a hassle for everyone if the parts fail, not to mention the delay caused when customer provided parts are incorrect or incomplete.
  • The professional mechanics at your local shop can order just the high quality parts they need for your job without paying for extras.
  • Most shops are owner operated family businesses that make a small profit on the parts they sell in order to pay for the tools and equipment needed to install them.

Help keep your local shop in business!



REM Polish ISF Gear Finishing Race Polishing Service

Isotropic Superfinishing – Ring & Pinion Gear Polishing

In-House Gear Finishing Service

Simply put, Isotropic Superfinishing significantly reduces the surface imperfections that remain after a Ring and Pinion Gear set is manufactured. The result is a cooler, quieter and longer lasting gear set.  At West Coast Differentials, the process we use is chemically accelerated vibratory surface finishing. This is technically not a polishing process, however the resulting finish does have a polished appearance. This process eliminates surface imperfections without removing material or changing the physical dimensions of the part.
This finishing process is widely used in racing applications where a conventional break-in process is not feasible, and where optimum performance is not an option.


  • Reduced Friction
  • Reduced Contact Wear
  • Reduced Heat
  • Increased Durability
  • Improved Oil Retention
  • Lower Operating Temperature
  • Reduced Noise & Vibration
  • Increased Fuel Economy
  • Reduced Break-In Requirements
  • Reduced Maintenance



We can Superfinish Ring & Pinion gears for practically any vehicle. Our extensive inventory of OEM and Aftermarket gear sets allows us to process and deliver your gears in the shortest possible time. Normal processing time is 1-2 days, depending on current scheduling.

Please call our Gear, Axle and Differential Parts specialists for details, pricing and scheduling.

(800) 642-0950

Gear Polishing REM Polish ISF Gear