Flush oil gear oil?

[Stewart Fan]

I've currently got Royal Purple max gear 75-90 in the diffs of my '07 Ram 3500. I'm going to change the fluid and O'Reillys had M1 75-90 on clearance for $8.99 a qt.

Do I need to flush the old oil out or will letting it drain well be enough?

 

[Eddie]

Just warm it up and do an extended drain.

 

[Cause4Alarm]

+1.....just a drain

 

[190E26FTW]

You dont really have to do anything, but it is best to let as much of it drain out as possible. Then close up the drain hole...put a little Mobil 1 in and turn your wheels which turns the gears. This is best done with wheels in the air of course. Then open up the drain hole and let the rest come out and see what color it is. If it is dark with metal flakes then do it again until it comes out Gold clear which is the color of Mobil 1 gear oil. I try not to mix oils too much because of competing additives.

 

[Bill in Utah]

Originally Posted By: Eddie
Just warm it up and do an extended drain.

+2. No need for anything else.

Drain and fill. No worries about this brand mixing with that brand.

I'd think with a ton truck that a x-140wt would be what I'd be using, Esp in the rear if towing. What does Dodge recommend?

Bill

 

[hisilver]

yeah, does not dodge recommend a 140 at least in the rear?

 

[unDummy]

Never need a flush unless you get a some water draining out.

Drain and refill!

 

[Stewart Fan]

Originally Posted By: Bill in Utah


I'd think with a ton truck that a x-140wt would be what I'd be using, Esp in the rear if towing. What does Dodge recommend?





The 11.5" AAM axle in my truck is the same that GM uses with their Duramax trucks. Both GM and Dodge recommend 75w-90,but I think its actually AAM that makes the recommendation.

For a while,Dodge was recommending a 140 in the smaller diffs of their half tons that towed frequently. Not sure if they still do in their latest models.