Upgrades with a stock 4.0l engine

thebarrabuggy

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QLD, Australia
I’d love to begin my plans on an over land Tj build and i’m curious on what i can do with the stock 4.0l I6 in a 02 Tj

I have plans on an engine swap but it isn’t ready to happen just yet, so i’m seeing what’s possible with the stock motor.
it’s only a 3 speed or 4 speed auto and have plans to put new manual gearbox in when swap goes ahead but what are the limitations now?
i’m hoping to put new Dana 44’s under it
35’ tires
lift kit on the taller side
overland if gear 4wd draws, fridge, roof rack ect
i understand it’s all extra weight but with regearing and a manual swap will the stock engine be able to comfortably handle it?

cheers guys
 
Nothing worth spending money on. If you have plans for an engine swap then save your money. The 4.0 works. Believe it or not some people actually wheel with the 2.5 and the 2.4. Amazing, I know.
 
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I’d love to begin my plans on an over land Tj build and i’m curious on what i can do with the stock 4.0l I6 in a 02 Tj

I have plans on an engine swap but it isn’t ready to happen just yet, so i’m seeing what’s possible with the stock motor.
it’s only a 3 speed or 4 speed auto and have plans to put new manual gearbox in when swap goes ahead but what are the limitations now?
i’m hoping to put new Dana 44’s under it
35’ tires
lift kit on the taller side
overland if gear 4wd draws, fridge, roof rack ect
i understand it’s all extra weight but with regearing and a manual swap will the stock engine be able to comfortably handle it?

cheers guys
Your 2002 came with the 3-speed 32RH automatic transmission. Forget easy or inexpensive upgrades to boost the performance of your 4.0 engine. What will boost engine performance considerably is regearing both axle's ring & pinion gears to 4.56 to counteract the loss of performance with your 35's. And do keep the 32RH automatic transmission, it's superb for offroading. I replaced my first TJ's 5-speed manual transmission with the 32RH automatic for s major boost in offroad capabilities.

Regarding your 35" tires, do you know if your rear axle is a Dana 35 or Dana 44?

Look at its differential cover to see if it looks like the Dana 44 on the left below or the Dana 35 on the right.

DCP01650.jpg
 
Your 2002 came with the 3-speed 32RH automatic transmission. Forget easy or inexpensive upgrades to boost the performance of your 4.0 engine. What will boost engine performance considerably is regearing both axle's ring & pinion gears to 4.56 to counteract the loss of performance with your 35's. And do keep the 32RH automatic transmission, it's superb for offroading. I replaced my first TJ's 5-speed manual transmission with the 32RH automatic for s major boost in offroad capabilities.

Regarding your 35" tires, do you know if your rear axle is a Dana 35 or Dana 44?

Look at its differential cover to see if it looks like the Dana 44 on the left below or the Dana 35 on the right.

View attachment 353708

it’s a dana 30 front and i’m confident it’s a Dana 44 rear
 
Nothing worth spending money on. If you have plans for an engine swap then save your money. The 4.0 works. Believe it or not some people actually wheel with the 2.5 and the 2.4. Amazing, I know.

i’ve seen a considerable about of people with a lot of gear strapped on and still running the 4.0
i spend most weekends away up the beach through the sand, it goes well. but with all the extra weight soon to be added will re gearing be enough?
all i’m asking is can i do all my suspension, wheel and accessory upgrades while still having a stock 4.0l
or should i wait on all the big mods until i’ve put a different engine in
 
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Gearing is what you need. Bolt on mods for a 4.0 will only help higher in the rpm band which isn't where you will need power unless you are drag racing other slow jeeps. A stroker would help, but that's far from bolt on and you'd still need correct gearing.
 
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i’ve seen a considerable about of people with a lot of gear strapped on and still running the 4.0
i spend most weekends away up the beach through the sand, it goes well. but with all the extra weight soon to be added will re gearing be enough?
all i’m asking is can i do all my suspension, wheel and accessory upgrades while still having a stock 4.0l
or should i wait on all the big mods until i’ve put a different engine in

You should share more about what your swap plans and intended useage are.
Yes you can run a 4.0 in a heavy jeep. But will it throw roostertails in the sand at 60mph? Probably not. Pull long steep mountain passes at 70 in overdrive? Probably not. Get where you're going slower the more crap you put in the back with regeared axles and 35s? Yes.

Tall and heavy with a lot of weight on the roof I'd be tempted to run the jk axles for stabilies sake.

What motor/transmission are you considering for a swap?the benefit of doing everything at once is not modifying driveshafts and other things twice. Other side of the coin is you can enjoy a jeep on 35s until you swap.
 
Only meaningful engine mods to a 4.0l are a stroker,supercharger or turbo.none are cheap. Spend the money on your engine swap if its happening anyway
 
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You should share more about what your swap plans and intended useage are.
Yes you can run a 4.0 in a heavy jeep. But will it throw roostertails in the sand at 60mph? Probably not. Pull long steep mountain passes at 70 in overdrive? Probably not. Get where you're going slower the more crap you put in the back with regeared axles and 35s? Yes.

Tall and heavy with a lot of weight on the roof I'd be tempted to run the jk axles for stabilies sake.

What motor/transmission are you considering for a swap?the benefit of doing everything at once is not modifying driveshafts and other things twice. Other side of the coin is you can enjoy a jeep on 35s until you swap.

these are all my thoughts exactly, the engine swap plans are huge, no weekend job that’s for sure, with the engine swap in mind a set of jk pro rock 44’s and something bigger in the back is the plan for diffs so i think i’ll enjoy it for now and do it all in one go
cheers guys
 
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Upgrade the 32rh with redline clutch’s, kolene steels, bullet accumulators and servos instead of plastic, stage 2 shift kit and whatever else they do the 904 mopar trans
 
5:13's in the diff's and spend money on lockers, in sand fairly low tire pressure and you will be totally fine.
 
it’s a dana 30 front and i’m confident it’s a Dana 44 rear

I have a 2000 TJ with the 32RH transmission, re-geared to 4:56 to run 35" tires & it moves along great. Just got back from a Moab trip & it performed great. An addition I did was add a 2 Low to the transfer case which allows you to stay in low range but in 2 wheel drive, really nice when on trails you really don't need to be in 4 wheel. Did this when adding slip yoke eliminator kit.
 
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these are all my thoughts exactly, the engine swap plans are huge, no weekend job that’s for sure, with the engine swap in mind a set of jk pro rock 44’s and something bigger in the back is the plan for diffs so i think i’ll enjoy it for now and do it all in one go
cheers guys

It's your Jeep, you do you. But I'm curious why you are so dead-set on an engine upgrade? Purely for overland adventures? I don't get it.
 
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