Differential Ground Clearance

The Ocala Jeep Club of Florida

Lack of Ground Clearance=Interference By Ron Tyrie II

The standard industry explanation of ground clearance is: the lowest portion of the vehicle to the ground measured in inches. Ground clearance is important because it indicates how far a Jeeps tires can sink into the ground before the vehicle is stuck as well as how rough of terrain you can go across without bottoming out. How far you can sink without bottoming out becomes important as your vehicle is searching for terra-firma. The following article is a dissertation on how to achieve maximum ground clearance without compromising too much on road handling.

There is really only one way to improve on ground clearance; that is to install bigger tires. However, oversize tires usually need suspension or body modifications of some sort in order to make way for the rubber. Unfortunately for the weary Wrangler owner, the Dana 35 (D35) is not designed to hold up to a tire much larger than a 33 incher. About the largest tire a Jeep owner can install without a serious deterioration of street handling is the 36 x 12.50 Super Swamper TSL radial. There is no way that a standard, locked D35 will survive the abusive onslaught the axles will undertake once these tires a taken down your favorite trail.

Serious modifications are now in order to allow the Jeep to make it over the first obstacle without breakage. Given an unlimited budget regarding construction. A Jeeper’s first instinct is to go “bullet-proof”. That basically means a modified Dana 60 (D60) cut down from a full-size ¾ Ton truck. While this would provide one with a rear-end that would hold together during any onslaught that could be served up by the driver, it may interfere with off-road performance. Engine power is a factor that has to be taken into consideration. A big horsepower v8 would necessitate the D60 unit. But the stock 6 cylinder as well as a mild v8 does not necessarily need so much beef. Why should one look to a rear-end other than the D60? Simply put, the D60 uses up almost 1 inch of ground clearance compared to a Dana 44 (D44) unit, and even more than that with the Super 35 D35 modification.

There are of course no rules regarding how an owner chooses to modify his or her Jeep. Just keep ground clearance and the vehicles intended usage in mind while you are shopping through the myriad of options when it comes time for modifications.