Ford Rear Differential Experts Please

[David/MN]

Ok it's not Walleye fishing, but it about getting to Walleye fishing.

I have a 99 Ford Expedition (No wars please I love mine), If I am not towing the boat, I am pulling the sleds around, so lots of wear and tear.

As I was rushing out of town I stopped at Jiffy Lube (I know, I know) for a quick oil change, and in a weak moment agreed to let them change the rear diff fluid, the computer said it was required ;-). Well to make a long story even longer, My brother in law tipped me off that the rear diff was filled with life time synthetic fluid, (that dosen't need checking or changing) and has a special friction additive for the limited slip freature.

Well according to the owners manual, and a call to the dealer he is right on (says not to even check the level).

What's worse I looked at the Jiffy receipt (was planning to get some money back) I noticed that they filled the rear diff with standard GL-5 gear lube!

Any thoughts? Did I just fry (or shorten the life of) my rear!

Planning to have Mr. Jiffy refund, and then pay to have the rear serviced by the dealer.

dw

[AquaMan]

I guess I would have asked the deal when you checked with them.

The most important thing, if there is any remaining, is did it void any warranty?

If the dealer confirms your fears and what Jiffy did was to void the warranty or shorten the life, I guess I would check with Jiffy and see what they are willing to do to correct the problem. Further, I would ask Ford what IS required to return that rig back to warranty status. That way there is not question what needs to be done.

In the end, the damage may have been done, but I doubt it. Once the seal has been broken, you risk the introduction of moisture and other contaminants into the pumpkin. Your dealer will be your best source for all this information.

Just FYI...last time I went to Jiffy, a guy flew in as red as a tomato and began screaming profanities about the fact that his 6 month old car was sitting up on the highway with a blown motor. Apparently the kid in the hole did not make sure the old seal came off with the old filter and spun on a new one. Not to say they are all bad, but why risk it. Kinda like eye surgery, do you go to the cheapest surgeon in town?????

AquaMan~~~~~~~~~~~~~~~~~~~~~

It all begins and ends at the water's edge...

[J.P.]

I'm not familar with the Fords but I work for GMC. General motors also went to long life fluids. They are a synthetic lube. They are compatable with conventional fluids but personally I wuoldn't mix them together. If they changed all of the fluid I don't think it will harm the axle. They have used regular gearlube for many years. As far as the manufactors recomendations on 100,000miles I disagree. Gears and bearings still wear and fine metal particles get in the fluid. Changing the fluid is the only way to get them out. I think your biggest mistake was going to Jiffy Lube. STAY AWAY! I would go to your dealer and have the right fluid put in. I don't think you did any damageas long as it is full.