Hey guys I'm having trouble navigating on my phone. I'm sure I can find the info here somewhere but, what kind of diff fluid does an '02 4.7 4wd use? I'm sure its 80-90 but what type?

 

First you may need to find out what kind of Diff you have, I am sure one of the experts will chime in here, but you realy need to know if its open or limited slip.
Limited slip needs the friction modifyer in it, or you will be sad.

 

I'm sure shrp will chime in because IIRC he has an '02 with the 4.7 and as far as I know all the Durangos take the same fluid. You can consult your owners manual in the back if you have one BTW.

75w-90 is the best weight to put in the rear end. Also if you have a LS make sure to get a friction modifier for a LS setup. IMHO you can go wrong with Mobil 1 75w-90 LS fluid because it's got a friction modifier but is also one of the best you can get for a regular open differential.

 

I did'nt know the Mobil had the " modifier" lol in it already, if I had I would have used that in mine when I serviced it instead of shelling out extra, thought I was saving a couple of $$, oh well, next time.

 

all the rear ends should take the same fluid as stated above, the 75w90 sounds about right to me, but i dont have my manual here (its at home in my glove box) but as stated the mobile one is some of the best you can buy

 

http://www.mobiloil.com/USA-English/..._75W-90LS.aspx

Check out that website for more information and yep, the Gear Lube includes the LS additive.

 

The technical "Type" of fluid is "Hypoid Rated" gear lubricant.


They used 2 different types depending on what it was built for. The trucks with the tow package installed factory the rear end is bumped up to the 75W-90 Fully Synthetic and the fronts are 80W-90 conventional. Also 4oz Friction Modifier if you have a Limited Slip Differential in the rear regardless of size. I always put a entire 7oz bottle from Auto Zone for $5.99.

Standard duty ones only had 80W-90 conventional front and rear.

Regardless, I would buy Mobil One LS Fully Synthetic 75W-90.

I asked Mobil One tech on this, he stated to ALSO use the Friction Modifier because one size don't fit all. But yes, it is rated for the front regardless of type.

 

Mine is a 4wd, I went and bought the valvoline 80-90 with LS already added in. Never messed with this LS stuff, but the bottle says its rated for conventional and limited slip. I'm hoping it means that the LS stuff is already added in and not just 'rated' to be used with it.

Damn it I hate change.

 

Yes we are talking about the same type fluids.


They have the Friction Modifier in them already so it should work, I don't like the "should" in that sentence. Like I said, I was told to use it anyway buy a Chemical Engineer tech for Mobil One company.

 

Question, if my garage forgot or did not put enough slip additive in, and I drove it at least 250 miles would this hurt my diff.

Question, if my garage forgot or did not put enough slip additive in, and I drove it at least 250 miles would this hurt my diff.