Jeep Gear Oil Question

[Johnny]

Jeep Wrangler owners manual says to use 80W90 in the front and rear differentials, but if you are going to carry any heavy loads or do towing to use 80W140 in the rear differential. Would it do any harm to use 80W140 in both differentials?

 

[Chris142]

I don't see a reason to put 80w140 in the front. If your in a situation where your highly stressing the front D30 the axles, carrier or spiders will break before the ring and pinon get damaged. LOL

 

[Johnny]

I have several quarts of the 80W140 is the main reason I asked. Hate to buy more if what I already have will work. Thanks

 

[Greaser]

The Rubicon model specifies "75W-140"syn in both dana 44's so I don't see any problem ,other than a slight drag till warm up, arising.

 

[Johnny]

Kind of what I was thinking but my Wrangler Unlimited has the Dana 30 in front and the Dana 44 rear. I also stand corrected as the gear oil I have is 75W-140.

 

[gomes512]

Yep you can use that 75w-140, my ZJ's 30/35 axles live on a steady diet of 85w-140 summer and winter since I have a whole heep of the stuff.

No problems what so ever, been doing this for 7 years now (around 90K). Last week when I popped the covers off and had the carriers out the bearings, ring and pinion looked A-OK on both the 30 and 35

I just recommend popping the covers off and flushing the inside with some fresh gear oil to remove any metal flaking you may see (I try to avoid flushing with solvents). Refill then do some tight figure eights in an empty lot and recheck the levels.

Happy truckin'

 

[Pablo]

110 or 140 would be fine, but don't use 90.

 

[Johnny]

Oh Pablo, I can't wait to hear the replies to that statement, "but don't use 90"

 

[Tempest]

Quote:
I also stand corrected as the gear oil I have is 75W-140.


Hmmmm....let me guess...Pennzoil???

 

[Johnny]

Actually hmmmm.....no it's not. We will just leave it at that. I will just say it has not been discussed on this board.