Sly Mongoose

I want to get rid of my 3.6 L and get something stronger or what can be done to soup up the original engine. It just doesn't have enough juice to pull up hill in 6th gear. Pulls ok on flat roadways and of course downhill.50,000 Miles on 2008 JK x four doors. Ideas about replacement? Or am I crazy? I'm running 31 x 10.5 tires and it's just a slug at almost any incline.

Jay2013jk

Welcome to JK Forum. See you are CA resident.. Before swapping out the engine check CA emission regs/laws.. What gears do you have? If stock going up to 4.10s might be a less costly proposition. BTW the 2008 had a 3.8L and yes it is under powered compared to 3.6; but it is good solid engine.

Sly Mongoose

I did miss that on the engine size.
I believe that the gears are stock, so I'll check out the gear thing.
I had done some research several years ago and that totally slipped my mind.
I'll revisit this option. Thanks for the info.
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SimpleSimon

I think the 2008 had the 3.8? I could be wrong. Anyway, I wouldn't expect to go uphill in 6th gear, that is overdrive if I'm not mistaken. 5th or even 4th is more suitable for uphill (and passing)

resharp001

yes, you have an underpowered 3.8L, and that life just is what it is. Forced induction is not really a good alternative. You'll just wear that engine faster and the added HP for that 3.8L with the superchargers really isn't even that much extra, especially for the $$$$$$. Proper gearing will help, but it isn't going to feel like you gained horse power. LS or hemi swap is the only real solution, and even those will have their own issues, including draining your wallet. This is just part of "jeep life" unfortunately.

The 3.6L was a nice improvement, but it sure isn't perfect either and when you weigh the jeep down with all the goodies and add big tires even that will turn a JK into a fat pig.