DanW
Well-Known Member
- Thread starter
- #1
Well, I had some leftover gear oil from changing the diff fluid on my JK, and from my buddy doing his, so I decided to go ahead and do a quick change on the JL's rear diff. I know, I know, it is way early, but I'm going to do some LONG highway driving and lots of crawling, and I had LOTS of gear lube, and it made me feel good. So there, that's why.
Anyway...I ran into a couple of surprises.
First, on the JK, with the towing package, and if you plan to actually do any towing, it specifies 75w140 gear lube. That makes sense, and my JK has done just fine with Walmart Supertech full synthetic. I just changed it out at 30k, and the fluid looked pretty good. I've done lots of towing, so 30k is a good place to swap it. It takes a little over 2 quarts in the Dana 44. I looked in the manual, and no matter what, towing or not, severe service, or not, it specifies 75w85, which isn't even synthetic. I looked and looked and saw nothing additional for severe service. Maybe I missed it? I went ahead and put Valvoline 75w90 full synthetic in it. (Update: It does recommend 75w140 for towing. I've since swapped Valvoline Synthetic 75w140).
The second surprise was how little the JL Dana 44 (M220) held. It did not hold a full 2 quarts before dripping out the fill hole. I'm pretty shocked at that. I couldn't find the published capacity in the manual, so does anyone know the actual published capacity? I want to say it took about 1.5 quarts, maybe a little less. I'm really surprised at this.
The old fluid, with 9,700 miles on it, looked pretty good, as it should, but it did have quite a bit of metal on the magnetic drain plug. It wasn't enough for any alarm, and seemed about what I'd expect from break-in. I was VERY tempted to go with 75w140, though, because I do tow a fishing boat on occasion. However, I stuck to the recommendation, since I'm running a good quality full synthetic.
I'm now curious what the front holds. I'm not going to bother with it, though. The JK's front fluid looked new at 30k and had almost no metal on the magnet. The JL, with it's disconnect, should put even less stress on the gear oil. It will go the full 30 or 36k, whichever the manual recommends. Same with the transfer case. The JK fluid came out looking brand new.
Anyway...I ran into a couple of surprises.
First, on the JK, with the towing package, and if you plan to actually do any towing, it specifies 75w140 gear lube. That makes sense, and my JK has done just fine with Walmart Supertech full synthetic. I just changed it out at 30k, and the fluid looked pretty good. I've done lots of towing, so 30k is a good place to swap it. It takes a little over 2 quarts in the Dana 44. I looked in the manual, and no matter what, towing or not, severe service, or not, it specifies 75w85, which isn't even synthetic. I looked and looked and saw nothing additional for severe service. Maybe I missed it? I went ahead and put Valvoline 75w90 full synthetic in it. (Update: It does recommend 75w140 for towing. I've since swapped Valvoline Synthetic 75w140).
The second surprise was how little the JL Dana 44 (M220) held. It did not hold a full 2 quarts before dripping out the fill hole. I'm pretty shocked at that. I couldn't find the published capacity in the manual, so does anyone know the actual published capacity? I want to say it took about 1.5 quarts, maybe a little less. I'm really surprised at this.
The old fluid, with 9,700 miles on it, looked pretty good, as it should, but it did have quite a bit of metal on the magnetic drain plug. It wasn't enough for any alarm, and seemed about what I'd expect from break-in. I was VERY tempted to go with 75w140, though, because I do tow a fishing boat on occasion. However, I stuck to the recommendation, since I'm running a good quality full synthetic.
I'm now curious what the front holds. I'm not going to bother with it, though. The JK's front fluid looked new at 30k and had almost no metal on the magnet. The JL, with it's disconnect, should put even less stress on the gear oil. It will go the full 30 or 36k, whichever the manual recommends. Same with the transfer case. The JK fluid came out looking brand new.
Sponsored
Last edited:
