DCox

Hey guys my rear axle is shimmed(not sure what degree as it came this way when I bought it). Anyways I just drained and inspected it, put the cover back on and when I filled it I only got about 1.5 quarts in before it started coming out the fill plug. It looks like it should hold just over 2 quarts. Any idea what I should do here? Will being half a quart short do damage? Should I jack up the rear of the vehicle and fill it the remaining half quart? If I were to do that will the rubber plug be enough to keep the oil from slowly leaking out. Not a big fan of the rubber plug, but I can't afford an aftermarket diff cover at the moment. Thanks for the help!

SatiricalHen

It'll just leak out the rubber plug, that's how mine was, I then got a solid differential cover which has a higher fill plug, but be careful not to over fill if you get an aftermarket cover because the guy who did my gears over filled mine and it leaked out the axle seals and out the vent tube. Also, if you have a locker they take up more space than the spider gears so less fluid will fit. I'm sure you'll probably be fine, but if you want peace of mind you could get a cover with a higher fill plug which screws in like I did.

Fred/N0AZZ

Anytime you fill one to the top it is overfilled, you should be able to place your finger into the fill hole and stick it down till you just feel the tip of it in the fluid. Sounds like you didn't get it all drained sometimes you have to suck it all out or put rags in the differential to remove all old fluid.

DCox

Thanks SatiricalHen, I definitely plan on getting a solid diff cover in the future.


Fred, I know I'm supposed to fill till it just starts coming out the fill hole. Problem is I have a shimmed axle which has caused that fill hole to be a good bit lower than it used to be, thus lowering the typical capacity of the diff. I was just wondering what people typically do in this situation. Should I fill it to the manufacturers capacity or leave it lower since the fill hole is now lower. I went ahead and lifted the rear of the jeep till the hole was where it originally was and filled it to the manufacturers stated capacity. Hopefully this is the correct thing to do.

Fred/N0AZZ

You will know if it's overfilled if you have leaks from axle seals for from vent tube.


I have shims on mine also but use aftermarket covers that have fill and drain plugs both for easier changing of fluid because I'm in water/mud a lot. I still remove them 2 times a year to check gears/lockers.


I have found on mine all I have to do is jack up the front of the XJ and it drains fully except for a small amount that I suck out with a bulb and nozzle. The front drains very well, this photo shows the drain plug the best I have for them.

DCox

Thanks! Well so far nothing is coming out of the seals or vent tube, but I also haven't driven more than 15 miles at a time. I'd love to get the covers with drain and fill holes as I'm also in a lot of water/mud. My plans as of right now are SYE and then the diff covers. I have a little bit of vibrations in the driveline with this lift from the previous owner, so I think the SYE is more important at the moment than the covers. What did your covers cost you?

Fred/N0AZZ

It's been over 4 yrs. since I bought them and can't remember exactly but around $140 I think, there are cheaper ones that have drain plugs also but in steel. I just liked the HD Ribbed Polished ones that said Jeep on them.

DCox

Cool, thanks again for the help!