Slowly working my way down the high mileage service checklist: got the stuff the changing the tranny fluid/filter, now getting the stuff for first time ever---changing the gear oil in both diffs----any advice on weights, brands? Should i just use the OEM?

 

85/140w was recommended to me. The factory recommends a lower weight. I recently changed both diffs and the transfer case, and it took almost 2 gallons for all 3. Remember to clean off the drain plugs, they have magnets that attract metal shavings, and use teflon tape on the drain plug threads when reinstalling. Also, not sure if this is mentioned anywhere, but the fill plug is plastic. Be very careful with it. I think the torque spec is something like 7 lbs/ft. Over-torque it and it will break. You can get a hand pump that attaches to the 1 gal jug at most autoparts stores. I broke one pumping the 85/140w, so be careful with that too. As with most fluid changes, take the fill plug out before taking out the drain plug. It lets air in to help the fluid flow out easier/smoother and it ensures you can refill it once its drained.

 

As for brand, I used whatever Wally-world sells. I went to 4 autoparts stores (2 national stores, 2 locals) and none of them had 2 1 gallon containers except for China-mart.

 

Consider doing transfer case while you are at it. Some say the thicker 85W150 in synthetic will quiet TC even more, but consider cost of change out if you go wading a lot.

 

I actually do not own a torque wrench! Just using my socket set. Sounds like I should get one asap.

 

Yeah, I would. The diffs use a 1/2" ratchet for the drain plugs (just stick the ratchet in the square drive, its a perfect fit), and a 21mm socket for the fill plug. If your going to be working on your Rover (or any car) ever again, invest in a torque wrench. For a beam type, they are short money. I try to stay with craftsman tools b/c I can't afford Matco or Snap-On, and I think a craftsman beam-type 1/2" torque wrench runs about $30, and a 3/8" runs about $20-25. I would either get one of each, or one and an adapter to change from 3/8 to 1/2, or vice versa. You can probably get one even cheaper off craigslist and still get the craftsman lifetime warranty, and there's always a sears nearby to return it too should you have too. Good luck.

 

Thanks for the advice on the torque, eaglerover, and for the socket sizes. Was going to ask about that. The last thing i need to do is shear off bolts because I'm too cheap to buy a torque wrench. . I'll get a craftsman.

 

85w-140, Tractor Supply Company house brand is what I use.

 

Make sure you us a synthetic fluid like factory used, 85/140 will give you a lot more wear protection and don't worry about a torque wrench, it is not needed.
On the t/case, first locate the fill plug before you drain it or you will have a problem.
The diffs. take 1.8 quarts while the t/case takes 2.2 quarts.

 

When deciding between synthetic and dino oil consider the price difference vs how often you'll be changing it (more often if you use under harsh conditions and/or lots of wading and how many miles you drive it.
There isn't any particular technical reason to run synthetic.

Consider replacing the plastic plugs with brass ones from Trevor at Rovahfarm.