What are you guys seeing for mpg drop when running 4x4? I'm not talking on the trail, talking snow, loose surfaces at in town speeds (25-40mph). I'm seeing my Jeep drop 4.5mpg when running 4x4, seems like a lot compared to other 4x4s I have owned. Don't really care either way going to continue to use it if I need it, just wondering. Going to dump the front diff fluid this weekend for synth, and thinking of doing the T-case as well. OH yeah it's a 97 4L with the AX15 normally seeing 16.5-18mpg drops to 12ish.

 

I've had my jeep for about 3 months and haven't got to run it in 4x4 for a long enough time to measure (too busy repairing it before I can have fun with it). I get about 11 mpgs so I'm already getting dirt haha

But I just wanted to say, DEFINITELY change the tcase fluid. Extremely easy to do and will only require about a liter of fluid to fill it (a quick and easy $5 for assurance)

 

I get from 10 - 12 mpg in 4 wd on snow and mud. 8 - 10 in the trails. 18 - 20 mpg in 2 wd on the road and in most trails, but I'm locked front & rear, so 2 wd has a lot of tracking and I don't use 4 wd as much as I did when I had open diffs.

 

Should be about the same...