A low slung white building greets visitors to the proving grounds. Housed within its walls are the engineers who design Eaton's differentials and other automotive products. It's a place where differential component and system testing occurs 24 hours a day and each test is setup and run following a rigorous methodology with meticulous care and documentation. Engineers dissect the components and results after each test, closely examining where parts might have broken, where they met or exceeded expectations and how to make them more durable in the future.
Eaton Test Engineer Todd Mumaw was our guide at the proving grounds and one of the first things he informed us of was that all newly arrived engineers must take a "Differentials 101" course before they can get down to business. In the class students study each type of differential hands-on, tear them down, build them back up and install them on a vehicle.
Mumaw began our tour with a visit to Eaton's differential wear testing labs where each room contained a specially built rack or piece of equipment to perform exacting tests.
In one room a 200 hour friction test simulated repeatedly locking and unlocking a differential. Its purpose was to identify the best lube and material combinations for use in the locker's disc pack and how this affected the coefficient of friction during locker engagement.
Next door was the gear impact test. Referred to by Mumaw as the "Big One", this test simulated differential engagement on the same gear tooth over and over again to find the optimum balance between strength and fatigue life in the materials used to manufacture the gear.
The engagement durability lab tested a combination of the differential's disc pack, cam plate and gear teeth through 20,000 engagement cycles to measure how well the differential would engage during a simulated lifetime of use.
But labs aren't the only place Eaton's differentials are put to the test and examined. The highlight of the day was a trip out and about on the proving grounds and practically nothing was off limits or out of reach.
Eaton's proving grounds are like the Q-labs facilities you find in a James Bond flick but without the explosions and bullets. There's a constant buzz of activity, people in lab coats, fast moving vehicles and multiple on and off-road courses calling out to your truck to be driven first. Where to begin? What's your pain?
We took two
trucks out for the purposes of comparison: a stock 2001 Chevrolet Silverado
2500 4x4 equipped with Eaton's optional OEM G80 mechanical locking differential
and a stock 2001 Ford SuperCrew 4x4 outfitted with a prototype Eaton ELocker
that replaced its factory limited slip rear axle. Inside, the SuperCrew
sported two buttons on the dash where the driver could choose to manually
activate the front, rear or both locking diffs. Both pickups also wore