Ok so our Jeeps lose a bunch of power in the drivetrain to losses. Im already talking about replacing my clutch on a new JKU because well it just feels too light to me to deal with big tires and all the extra mass I have added already. What if anything have people been doing to improve driveline losses.

Synthetic diff fluids?
Aluminum Driveshafts?
Aluminum Flywheel?
Lighter wheels and tires? Not really possible

Anyone have any input on this at all? Best I can figure we lose 30-40% in the drivetrain on a Jeep. That is pretty bad. Most sport car types lose something like 13-15%. I realize our driveshafts are much heavier and well longer but has anyone messed with this idea at all?

 

A lot of JK's owners will drop wheel size. Opt for a 15" or 16" alloy.
My 35x15 KM2 is light compared to others.

Company's like RK offer a all aluminum kit.

The obvious not running a spare.

Driveshafts/flywheel. doubt it

 

I think the 30-40% range is believable for automatic transmissions. I bet the manual is closer to the 15-20%. The clutch would have to be slipping for major losses. You are on the right track on reducing friction losses and mass.

 

I think the difference between manual and auto is closer these days. If the auto were in the 30% to 40% range, I wouldn't be getting 22 mpg hiway/18 around town. I haven't seen any similarly equipped JKs with a manual transmissions get much better than that.

 

Im just going off of stock dyno numbers I have seen for RWHP figures. Most I have seen are like 180-185 RWHP with the new engine. Mopar advertises the 3.6 as putting out 285 hp at the crank. That is a 100hp loss assuming Mopar isnt lying too much. That is a pretty large loss to move the drivetrain I think. Im thinking there has to be a way to get some of that back.