I recently saw the dealership wanting $300 to do a 4x4 service. From what I can tell it just involves changing the fron/rear diff fluid and checking the x-fer case level. I'm not going to pay that for something that looks rather simple. I know The manual calls for 75-90, in the front and 75-140 int he rear. I'm planing on using synthetic for both. What I don't know if I need to use a friction additive to the rear. Its an 4.7 awd/4wd and I have no clue if it's an limited slip diff. Also I can get a straight answer on the levels. It's an 06 but only has 30K on it so I didn't plan on pulling the cover. I'm just going to vac it out and refill.

 

you do not need a friction additive and transfer case is easy drain and fill with 2 litre of tranny fluid

 

Use ATF-4. The FAQ has the fluid capacities,
FF

 

DES:

Absolutely DIY is the way to go here. You can save yourself a bundle. Synthetic is the way to go, and using s pump to remove the old diff fluid is fine.

I would go ahead and drain/refill the T case as it is very easy, and good PM!!!!

Don

 

What about the levels? Is it to the hole or the levels I've seen some mention via the TSB.

 

Desmann:

As long as the fluid level is no more than a half inch below the fill hole, and no closer than a quarter inch, you should be good to go.

Don

 

I've been reading that the synthetic lubes have the friction modifier already in them (RP & Mobil 1) Since I don't have an anti-spin diff will it harm it? I don't think Amsoil has it in it already. Anyone know if the stuff they use at the dealer has it in it or do they just add the modifier for AS diffs.

 

Desmann:

I believe that both RP and M1 have the modifier in them, but Gen 2 4x4 Durangos do not have a limited slip/Posi carrier. The front and back are both open.

I have used both RP and M1 and have had great luck.

Don

 

So It doesn't matter if it has the friction modifier when I don't need it? It won't ruin anything?

 

Correct!

Having it and not needing it is fine, and will do no harm.

The other way around is not so good, and usually equates to a noisy diff that chatters a lot on turns.

Don