[J-dawg]

I show the following for a '99 Trooper, and I'm pretty sure they apply to my '98 Trooper as well ...

Front Differential: 1.5 Qt. 80W-90 or GL-5
Rear Differential (G80, w/ LSD): 3.2 Qt. 80W-90 or GL-5 w/ Limited Slip additive
TOD/transfer case (ATX): 2.0 quarts Dexron III ATF

I've got some good synthetic 75W-90/GL-5 gear oil (Redline 75W-90) that says it already has LSD friction modifier, so I was going to use it in both front and rear diffs as-is, and I've got their Synthetic D4 ATF for the TOD unit. I wanted to run synthetics because a) I want to run an extended interval change (say, 45k), b) I'm trying to eek out every last bit of gas mileage I can, and c) I've got larger-than-stock (265/70/16) tires that I'm sure put slightly more load on the gears.

Can anyone confirm I have the right capacities for my '98, and does anyone have specific experiences to say that I've definitely got the wrong fluid for any of the above?

Thanks!

Josh

 

[mdocod]

not sure about the capacities- but the redline should perform in all those areas you mentioned a desire for better performance. it's good stuff, redline doesn't fool around.

 

[bigpoppax2]

As far as the amount of fluid, put it in till it comes out the fill hole. Then you have put enough in.

Joe

 

[Tad]

I want to run an extended interval change (say, 45k), b) I'm trying to eek out every last bit of gas mileage I can, and c) I've got larger-than-stock (265/70/16) tires that I'm sure put slightly more load on the gears.

Thanks!

Josh

I think that synthetics are just fine and I use them myself when they are available, but I thought that I'd add a couple of comments.

1) Change the TOD fluid and transmission fluid at the factory intervals, synthetic or not. The TOD fluid will get murky (contaminated) over time simply due to the normal TOD action which causes material to wear off of the clutches in the transfer case. There is no filter in the transfer case so those particles just float in the fluid until you drain it. The transmissions aren't cheap and changing the fluid is cheap. You'd be upset if saving $20 on fluid caused you to loose a transmission.

2) The differential gears in these trucks are overbuilt. You could run the cheapest fluid in them for hundreds and hundreds of thousands of miles and never wear out the gears. Given the change interval, the added cost of synthetic certainly won't break the bank though. Synthetic has been proven to increase gas mileage though so on that note go for it.

Keep up with these maintenance items and you'll be happy with the Trooper for a long time.

-Tad

2) These transmissions