Lifted pinion angle for SYE

When fitting a SYE it is common to lift the pinion of an axle to point towards the transmission output shaft. However when ones XJ has a lift in the region of 6" like mine, that angle is relatively substantial. I've measured mine with the angle finder to be about 13-14 degrees. The worry I have is the lubrication of the pinion bearing inside the diff. Is it possible for the bearing to run dry due to the angle the pinion points upwards? If it is, how does one counter this - do we just add more diff oil?

you want your pinion angle to be 2 degrees down from your driveshafts angle. i wouldnt wory about the pinion berrings not getting enough oil, they will be fine, just add more oil if your still too uncomfertable with it.

I fill mine the normal way, no problems yet.

I wasn't going to worry about it until the agency that did the ratio change mentioned it to me (they're providing a 40000km / 1 year warranty on the axle, so I guess they have their interest to protect). The guy mentioned to me that in the standard vehicle the diff runs in a completely horisontal position, so taking that as a base, here's what I did.





Seeing that the pinion was going to point upward at 14 degrees, I pointed it down 14 degrees before filling it with the gear oil. In theory this should put the oil level at the pinion to the same level it should be. I might pose a little problem when its time to replace the oil though - will have to jack up the rear quite high and then loosen the UBE bolts as well the get the pinion to point down 14 degrees again.

That's clever.


Just park on a hill when you replace the oil. Or won't it be enough if you drive the rear up onto ramps?

This was a new diff install and in the pics was the first fill, thus it still being on the trailer after the new gears were fitted. If it was already in the Jeep, then yes I would have just looked for a nice incline - a 28 degree incline to be precise!