We discover how to check and alter the rear hub free play on an E-Type
THE FACTORY spec endfloat for the Jaguar IRS is .002”-.006” for early models and .001”-.003” later. It’s important to have some movement because if there isn’t any, there’s a greater risk of overheating the wheel bearing and shearing the end of the driveshaft, which means the road wheel could fall off.
Knowing how much movement is at the hub can be accurately measured with a dial gauge, as we show here, but it also takes experience to judge the free play simply by waggling a road wheel by hand, as we discovered.
As Ken explains: “If you push the top of the wheel in and out, any initial play is in the wheel bearings. Secondary play can be movement in the half-shaft UJs and differential output shaft bearings.” So, a light waggle of the wheel is sufficient and if the footbrake is applied, there should be no movement in the output shaft bearing.
Adjusting the amount of free play is a potentially time-consuming job. There’s a shim inside the wheel hub that needs to be measured and changed, and reassembly is fiddly because there are holes to correctly line up for fitting a split pin. Not forgetting the official method of knocking back the bearings and correctly tightening the wheel spinner using a soft-faced Thor workshop hammer. Fortunately, technician Dan Fong (as shown in the photograph above) at Ken Jenkins’ workshop has lost count of the number of times he’s completed this job and was able to show us how it’s done properly.
