We have a 14 with 4.10 gearing and an auto with 35'sand a lot of armor. I have no issue with the power of the jeep. Afterall, I knew I was not buying a race car. You may be surprised at what correct gearing will do.
Jku Engine Swap options
- Thread starter Stroked 550
- Start date
Stroked 550
Adventurer
Its not about having a race car its about having a vehicle that can maintain the posted highway speed with ease
I've driven other jeeps with stock tires and they are sluggish too thats how they are but it looks like jeep is wising up because of the Bronco and the engine options they have
I've driven other jeeps with stock tires and they are sluggish too thats how they are but it looks like jeep is wising up because of the Bronco and the engine options they have
D
Deleted member 9101
Guest
You'll get run off the road here in Central Fl if you can't merge or maintain your speed....lol.
wADVr
Adventurer
A quick Google search turned up some concerning reports of dealing with this company. I like the idea of a stroker motor as apposed to swapping in an LS or Hemi to get the power up to an acceptable level BUT I also prefer stock components when possible, even if they are other vehicles stock components to make up my vehicle. From my XJ days and people stroking the 4.0 inline6 to 4.5/6/7/8 and seeing the tuning, issues changing parts etc to get it right I just dont see it as a viable option for reliability. In my opinion, the Hemi swap is pretty tried and reliable and it seems the LS swaps are just as good but seem to get back into that tweeking to get it right, I am probably not up to speed on LS swaps but that is my interpretation putting a GM motor/ECU/can bus into the Chrysler BCM/can bus.
In addition, I am not a fan of the terrible (IMO in an heavy JK) 42rle auto transmission in the 07-11 JK. Boosting or increasing displacement on the 3.8 still leaves you with this piece of crap transmission that cannot put the power down to the ground effectively or reliably. Just my opinion.
Getting myself confused on which thread I am on, I would recommend getting your axle gears sorted out first UNLESS you have unlimited funds and ability/time to swap engines is the best first step, if nothing else to help that transmission last a little longer. My previous post may be a little contradictory to that statement but combining the threads I am a bit unsure on what youre expecting from either of these modifications (axle gearing/power increase). If youre running less that 4.88 axle gears swapping will be a noticeable upgrade that might be all you need and would be even better with more power. If youre looking for more than just making it not frustrating to drive (engine swap/etc) my recommendation would be AEV 5.7 545 auto swap. It will work like it was meant to be there, service at dealer or other places without a huge explanation etc. Need a replacement motor or transmission down the road just get a factory replacement instead of doing anything custom what may bot be available years down the road.
agent00111
New member
I was going to re-ask the 'engine swap recommendation' in a new thread, but thought I'd just append to this to keep stuff in the same place.
I have a 2008 JKU rubicon wrangler. I've added 37's and regeared to 4.88. Stock engine I believe is the 3.8L v6 (the 'gutless wonder' as I call it). It was probably all fine in my first few years of ownership, but over time my jeep, like COVID-me, has put on weight (RTT, awning, jeep kitchen, etc). On the freeway I can get up to 70-80mph no problem. Desert and offroading, 4Lo takes on the hard stuff. There's just some times like going up a hill or into the wind where it really struggles to find gear and that makes the road trips less fun.
At one point I almost got talked into a new LS3 engine, which would have triggered axle swaps, etc.
Currently, I just have a really well loved overland jeep that I'd like to keep around for another 10 years, and I love everything about it except the engine performance.
What recommendation could you fine folks make that would better fit the bill, either new or used? Straight up overland stuff, not trying to make my jeep into race-car or sound neat. I'd rather focus on reliably, power, and gas mileage (I think I'm down to 11-12mpg).
I have a 2008 JKU rubicon wrangler. I've added 37's and regeared to 4.88. Stock engine I believe is the 3.8L v6 (the 'gutless wonder' as I call it). It was probably all fine in my first few years of ownership, but over time my jeep, like COVID-me, has put on weight (RTT, awning, jeep kitchen, etc). On the freeway I can get up to 70-80mph no problem. Desert and offroading, 4Lo takes on the hard stuff. There's just some times like going up a hill or into the wind where it really struggles to find gear and that makes the road trips less fun.
At one point I almost got talked into a new LS3 engine, which would have triggered axle swaps, etc.
Currently, I just have a really well loved overland jeep that I'd like to keep around for another 10 years, and I love everything about it except the engine performance.
What recommendation could you fine folks make that would better fit the bill, either new or used? Straight up overland stuff, not trying to make my jeep into race-car or sound neat. I'd rather focus on reliably, power, and gas mileage (I think I'm down to 11-12mpg).
wADVr
Adventurer
4.88s are still a bit high for a 3.8/auto JKU on 37s IMO I ran 5.38s to get it reasonably acceptable. it lasted 207k that way before the tranny let go but the engine was absolutely tired as well.
I am still running the same 5.38s/37s with the 5.7 Hemi and it works great. I get 16mpg on road trips better if under 70 worse if over. Overall daily grind which is a lot of stop and go during the work day is 14.5 regularly. If I re gear to 4.56 or 4.88 I believe that will improve a decent amount. That and my post above all said, I still stick with my opinion that the AEV 5.7/545 auto swap is best.
if I were to do it over again I’d look into the 2.8 Cummins a little more now that I know how to run the 8 speed on anything but that’s getting into custom stuff that requires tinkering (which I like but many shouldn’t)