Quality Differential Parts since 1982!


Quality Brand-Name Parts Ready to Ship TODAY!

Brand Name Differential Parts


We stock a huge selection of Differentials. The following is an overview of the types that are available. To find a differential for your vehicle, view our Differential Application Guides

For personal service, call our staff of differential experts at (800) 510-0950 for LIVE assistance.

Stock Replacement Open Differentials

Open Differentials

An open differential allows both tires to spin at different speeds. This is perfect on dry pavement when the vehicle corners and the axles turn at different speeds, but it doesn’t work very well when one or both tires lose traction. In this situation, the tire with no traction spins, and the tire with traction does nothing. Open differentials are available as complete units, or as separate cases and internals, from both OEM and aftermarket manufacturers.

Find an open differential carrier for your specific application in our Differential Parts Guides  under the “Cases & Internal Parts” section.


Limited Slip and Positraction Differentials

Limited-Slip Differentials

Limited-Slip Differentials generate more traction than the open differential. Most Limited-Slip Differentials, sometimes called posi’s or positraction differentials, use clutches to drive both tires, but allow the clutches to slip when the vehicle corners and the axles need to turn at different speeds. However, the Detroit Truetrac & Wavetrac® units act as open differentials but apply torque to drive the tire with the most traction.

Read more about our selection of Limited Slip-Differentials including Eaton Truetrac & Posi, Wavetrac, Auburn HP, Pro and OEM units

Find a Limited-Slip / Positraction for your vehicle in our Differential Application Guides


Locking Differentials Automatic Selectable

Locking Differentials

Locking differentials use various means to lock both axles so that both turn all the time. Automatic locking differentials disengage when the vehicle decelerates for corners. Selectable lockers allow the driver to engage the locking differential with a button. A locker ensures that both tires turn in all driving conditions. Lockers are ideal for more extreme off road driving. Learn more about our  Locking Differentials including Detroit Locker, Lockright, ARB Air Locker, Eaton ELocker, Auburn Ected and OEM Units.

Find a Locking Differential for your vehicle in our Differential Application Guides


Full Spool and Mini Spools for racing


A spool is a solid carriers that does not allow axle differentiation. Both axles turn all the time. However, spools can’t disengage like a locker, so the tires will chirp when the vehicle corners. Tire wear will increase. Spools are most often used in racing applications, and occasionally in off road applications.

Find a Spool or Mini-Spool for your application in our Differential Application Guides


To find a differential for your specific vehicle, view our Differential Application Guides or call our staff of differential experts at (800) 510-0950 for LIVE assistance.

Order Parts

Our Differential Parts Experts are ready to take your call Monday thru Friday from 8AM to 5PM.

(800) 510-0950

Most orders received before 4PM Pacific Standard Time will be shipped out the SAME DAY, with next day delivery via ground service to most of the West Coast!
We do not offer Online Ordering We want to make sure you get the right parts... Simply give us a call! Let our parts specialists take the guesswork out of your order.

Traction Devices

AAM Differential Kit

Open Differentials vs. Locking and Limited-Slip Differentials

Open differentials are standard equipment on most vehicles. The "Open" differential does a great job of transmitting power and propelling the vehicle forward. The design also allows both wheels to travel at different speeds while cornering, without causing excessive tire wear. The problem with the open differential happens when one tire is on a low traction surface such as ice, snow or mud. The tire on the slippery surface will spin while the other tire provides no forward motion. The animation above shows an open front differential in a 4-wheel drive vehicle. Differential upgrades that will provide power to both wheels are featured on this page.

2015 Product Catalog

West Coast Differentials Ring Pinion Axles Rearend Parts Click the thumbnail above to view or download our current catalog. Download a PDF copy and save it on your computer for offline viewing or see the Flipbook version online.