98 Expedition Rear Axle - Fluid and Modifyer

[PowerSurge]

^^^^This is bad advice. I've changed rear diff fluid on many Ford LS axles and the lubes that come with FM usually won't keep the axle from chattering.

Add the Friction Modifier and be done with it.

 

[bdcardinal]

Also when I sell XL-3 over the counter, I put it in a thick ziploc type bag for the customer. I tell them "trust me on this one" if they say anything.

 

[mobilaltima]

no sealant. just use a fel pro gasket, or better yet, a lube locker gasket, torque the bolts to spec and sleep well.

 

[Fitz98]

Any opinions on Valvoline vs Mobil 1 LS gear oil?
The Valvoline is about 13.00/qt and the Mobile 1 is 20.00/qt.
I don't care about 20.00 difference in price for 3 qts if the Mobil 1 is a better product, but also don't want to waste money if there is no difference.

 

[4WD]

Originally Posted by Fitz98
Any opinions on Valvoline vs Mobil 1 LS gear oil?
The Valvoline is about 13.00/qt and the Mobile 1 is 20.00/qt.
I don't care about 20.00 difference in price for 3 qts if the Mobil 1 is a better product, but also don't want to waste money if there is no difference.

What I posted in another thread … looks like roughly half is PAO/esters and half Grp3.
Appears some lab work went into that cocktail

 

[ls973800]

Just wanted to add one other thing to consider if you are doing this work inside a garage. Make sure you leave enough room between the wheel that you are pulling the axle out of and the wall or any other item that may prevent the axle from pulling out all of the way!

I did my 2003 F150 in my garage and hadn't even considered that. I was very lucky when I removed my axle and found I had just enough room to actually take it out completely.

 

[WyrTwister]

Does it hurt to use limited slip gear oil in a " regular " diff ?

 

[OVERKILL]

Originally Posted by WyrTwister
Does it hurt to use limited slip gear oil in a " regular " diff ?


No.

 

[Fitz98]

I did not understand the Mobil 1 analysis.
Does that mean it is good, or not so good?
Need to decide whether to get 20.00 M1 or 13.00 Valvoline.

 

[Fitz98]

The rear seals I got were pre-greased, but not very well.
Should all the spaces be filled with grease?
What type of grease would I use to lube up these seals. There seems to be many types of grease available.

 

[Black_Thunder]

Do the axle bearings look ok?