98 xlt 4wd 4.0 sohc rear diff fluid change

[jm]

I am going to change my rear diff fluid this weekend and I want to use synthetic, any suggestions?

Mileage is 112K, non submerged axels - to my knowledge.

Do I need a friction modifier??

Which synthetics are best?

Thanks in advance...

 

[gijoecam]

You'll need the friction modifier if you have the limited slip. As for oil, stick with a name brand and you can't go wrong.

Also, make sure you can remove the FILL plug before popping the cover to drain it. Otherwise, you'll be on here Saturday night asking how to remove the fill plug because you can't get it to budge and your diff is now empty. There's no point in draining it if you won't be able to refill it.

-Joe

 

[BrooklynBay]

I use the Richmond Gear differential fluid. I drilled out the cover for 2 drain plugs. The top one refills it, and the bottom one drains it.

 

[stubborn1]

If you are doing the rear, you may want to think about the front as well. It isn't that hard as long as you use a vacuum pump/fluid extractor to pull out the old oil.

 

[rizzjc]

I use Amsoil Severe Gear in mine. No friction modifier needed, but they have it, if you really want to put it in, but if there is no "clatter" then you don't need it.