37's on a 3.8L JK? what are your thoughts
06-01-2016, 02:10 PM
#11
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06-01-2016, 02:11 PM
#12
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There's numerous axle, steering, and proper suspension setup that goes into it. Google planman and 37s good info there to follow and how to make it work. Looks are one thing, function is another. I'm in NJ too if your not too far i could show you my setup on 37s.
06-01-2016, 03:19 PM
#14
Beef up the front axle housing a bit. Don't waste your money and go overboard on a D30. Gussets, hammer in sleeves and proper ball joints.
Chromo's in the rear are a nice option
Hydro assist is a must in my opinion (steering would jam up on my old tires that measured 34')
Invest in a heavy duty draglink and tie rod when you have the funds
Trim all the sheet metal
Lose the greaseable u joints. They're hollow making them inherently weaker
Chromo's in the rear are a nice option
Hydro assist is a must in my opinion (steering would jam up on my old tires that measured 34')
Invest in a heavy duty draglink and tie rod when you have the funds
Trim all the sheet metal
Lose the greaseable u joints. They're hollow making them inherently weaker
06-01-2016, 03:19 PM
#15
I'm manual shift so I can't comment about autos, but with 40s and 5.38s and the 3.8 liter I'm fine with it. It's not fast but it does fine (I know it's a Jeep and not supposed to be fast). It climbs hills fine but definitely have to down shift and run higher RPMs. As for steering, I ran 37 13.50s for awhile and turning sucked. I changed to 37 12.50 and it was fine again. Now I'm back to a 13.50 with my 40s and I have hydro assist.
Oh, forgot to mention. I have the Flashpaq tuner and I do notice a small difference with it. I run the 93 octane tune and when I put it back to stock tune it doesn't pull up hills as well.
Oh, forgot to mention. I have the Flashpaq tuner and I do notice a small difference with it. I run the 93 octane tune and when I put it back to stock tune it doesn't pull up hills as well.
Last edited by T&ERun; 06-01-2016 at 03:23 PM.
06-01-2016, 07:38 PM
#16
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I have this setup with a variety of the tweaks others have mentioned; check my sig info below. Happy with it, but I live where it's flat. Drove from TX to Ouray Colo and it was pretty miserable getting there and back due to the 3.8 and 5.13's just not being enough oomph over the passes on the highway. Off road it's fantastic though. In 4lo you'll have no issues whatsoever.
I have not done anything to my steering and haven't bent or broken anything. And it works fine for me. I did crack my original rubi D44 housing, so I have a ProRock 44 and feel a lot more confident. And front RCV axles. I use an AEV Procal to adjust for gears and such. I don't have any rubbing or flex issues with the 37's, but that's with flat fenders. Get some better ball joints, or be prepared to replace them more often.
Overall the 37's are fun off road and they look great. But like many have said, it's a real push with the 3.8, Auto, 5.13's, and 37's. 5.38's would be better, but a Chevy LS motor would be best.
I have not done anything to my steering and haven't bent or broken anything. And it works fine for me. I did crack my original rubi D44 housing, so I have a ProRock 44 and feel a lot more confident. And front RCV axles. I use an AEV Procal to adjust for gears and such. I don't have any rubbing or flex issues with the 37's, but that's with flat fenders. Get some better ball joints, or be prepared to replace them more often.
Overall the 37's are fun off road and they look great. But like many have said, it's a real push with the 3.8, Auto, 5.13's, and 37's. 5.38's would be better, but a Chevy LS motor would be best.
06-02-2016, 07:43 AM
#17
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06-02-2016, 08:51 AM
#18
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2011 JKUR with 37's and 5.13s and I absolutely with I would've gone wit 5.38's. Not that 5.13s are horrible on the highway, but it gear hunts a lot and I can't imagine trying to drive in the hills/mountains with it. Eventually I will be doing an LS swap. But it's not high on the priority list, as my Jeep is no longer a daily driver.
As has been mentioned, it sounds like you have a pretty solid setup, but definitely look into gussets/sleeves/truss on the front axle. If you're already looking for a D44, then I would do much to the D30 other than maybe gussets. But definitely add a heavy duty drag link & tie rod, along with some at least greasable ball joints. Synergy/Poly Performance makes great options for all three of those parts. And their tie rod uses 1-ton TRE's. From there, hydro assist would be a great option for off-road. Even on-road you'll notice a difference in steering feel Don't necessarily have to spend $2k on a full blown hydro setup. Look into the redneck ram, which is considerably less expensive and still works really well.
As has been mentioned, it sounds like you have a pretty solid setup, but definitely look into gussets/sleeves/truss on the front axle. If you're already looking for a D44, then I would do much to the D30 other than maybe gussets. But definitely add a heavy duty drag link & tie rod, along with some at least greasable ball joints. Synergy/Poly Performance makes great options for all three of those parts. And their tie rod uses 1-ton TRE's. From there, hydro assist would be a great option for off-road. Even on-road you'll notice a difference in steering feel Don't necessarily have to spend $2k on a full blown hydro setup. Look into the redneck ram, which is considerably less expensive and still works really well.
06-08-2016, 07:56 AM
#20
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