So the correct fluids are 75W-90 in the front and 75W-140 in the rear? I haven't looked in the OM, but 15k sounds awfully soon. I would think 30k intervals on them and the tranny/xfer case would be "normal".

FWIW, the Raider is the wife's truck, and I'm looking at the maint schedules now. BTW, what ATF goes in these? I'd like to go syn, and I run Mobil1 in my truck ('02 Ford F250 PSD). Can we run Mobil1 in these??

 

the synthetic 75w140 is the ONLY fluid to be used in the read differential on these trucks.

 

For the Tranny it takes ATF+4. If it's an XLS there is no front diff, they were all 2wd.

 

My 06 XLS is AWD & 4x4

 

Has anyone heard of the 06 raider having a posi rear differential? I purchase one a couple of weeks ago and I just realized that both wheels are pulling together. I also notice a slight vibration when taking off in a tight right or left turn. This will generaly only happen after the truck warms up real good. If this is a posi rear what indication would there be stating this? If not, what kind of trouble am I looking into repairing this?

 

Yes, I have a posi. The 3.92 have limited slip and the 3.55 are open diffs.

 

Ours is a DuroCross -- definitely 4WD and definitely Limited Slip rear end. If yours is chattering too much nitro, try adding a little extra friction modifier. Add 1oz. and try drive it some. If it needs a little more, add another oz. Don't put in too much at once, or it'll be a "Limited Grip", essentially making it an open diff. I've been thinking about putting a little more in ours -- every time you make a turn and step on the accelerator a little, it squeals the inside rear tire.