JKdreamer0309

Wanting to run 37's on a JKU automatic tranny. Aiming for 3" lift to avoid drivetrain issues along with flat flares if necessary. I will be rarely using the rig for off-road purposes. My question is... What other mods will I need to make to make this a solid regular driver? Gears? Are bigger axles necessary? Bigger Knuckles and U joints necessary? Bumps tops?

This will be my first build for a weekend/daily driver. Please help. Thanks!

d. gage

I'm thinking of this same route. I hate doing things twice and I don't want to put 35s on and only be happy with them for a few months...

JKdreamer0309

I'm afraid of the rumors I have heard about snapping axles and further undercarriage damage. I hate to run into a money pit. But just using it as a regular driver without off-road abuse shouldn't cause all of those issues should it?

d. gage

i see no reason for damage with the wheeling that I do, i'm looking for ground clearance over anything.

JKdreamer0309

What set up are you working with currently?

NUKEM-10

First off you will need to trim the rear pinch seem to keep your tires from rubbing. To get your overdrive back you will need to regear to 5.13 or 5.38 depending on the part of the country you live in, if you have a rubi then go 5.38 if not go 5.13. You will need to beef up your Cs with gussets, I wouldn't worry about sleeves or a trus sense its mostly gonna be a DD, but it doesn't hurt to over build. And you will probably need bump stops but don't what size, so your gonna have to figure that out. And that's really about it.

lkjk

tons of threads out there on it, search.

I will say this - those are some big tires for a DD, its gonna cost you for the tires, gears unless you have the 3.6 with 410s already (hopefully you do with the d44), and a good lift, not just a bunch of brackets. Even after all that, which isn't really doing it right, it's still not going to drive that great on the road and off road i would baby it. seems (wait, it is) pointless to put 37s on a jeep you aren't going to take offroad. and not to be the bearer of bad news but whenever i see a lifted jeep (35s or 37s) that doesn't wheel it I cringe...pricey, ruins mpgs and drives worse than stock as a DD

doing it right would be lift with control arms, track bars, sleeves or truss, c gussets, gears if you have a d44. Your bjs will go out sooner, possible need/want for steering upgrades and there are other issues that might arise. personally a waste of $$ for all that if you don't wheel it, but iffy to do without.

JKdreamer0309

Thanks for the info first of all. I am debating 35's vs 37's and everything I hear keeps leading me to 35's. So... If I go with 35's is a regear necessary on a auto tranny? And I want to keep stock fenders so I'm thinking a 3 inch lift would be best... For a daily driver should I go with a mid arm lift vs. short arm?

nthinuf

Fill in your profile and add some info.

3.6's and 3.8's have different gearing needs. 3.8 autos and 3.8 manuals have different gearing needs. Flat roads at low elevation vs mountain passes at high elevation. Lots of high speed freeway vs mostly in-town or offroad. See where this is going?

Housing upgrades are a personal preference, and you do NOT have to be smacking rocks offroad to bend or shatter the housing. That just greatly increases the chance. A pothole or curb can do it if you happen to get lucky. (or unlucky, I guess).

Case in point...
https://www.jk-forum.com/forums/stoc...e-help-161915/

3" will not avoid drivetrain issues. They will just be less likely, (or less severe) than with a 4" or 5" or 6" lift. Bigger axles? More for off-road, but as shown above, yes there is the possibility of failure from strictly on-road driving. Bump stops will depend on the specifics of the lift and how your jeep is set up. Knuckles? No. Ujoints? Run them til there is a reason to replace. Balljoints? Plan on it, if/when they fail (with 37's, plan on this being when, not if). Axle shafts? Wait until they fail, but have a replacement in mind for if/when the rear flanges bend. Front driveshaft? Flex and make sure it has clearance, (exhaust, crossmember skid, corner of the tranny pan). If it is contacting in the middle of the shaft, a thinner aftermarket may be needed. If clearance looks ok, then you will still want to make a habit of crawling underneath and looking! When the tcase joint starts to go, the ring of grease splatter will be very noticeable. The rear driveshaft should be ok on 4door at that height. But, your pic is a 2door? If so, watch the rear shaft as well.

For the JK, the arms are fairly long with respect to previous models, so it is more of a 'long arm' or 'not long arm', and not really long vs mid vs short. Short arms work fine. At 3", you can add front ca drop brackets to improve the ride if you choose.


And if you haven't found them yet, there are two threads stuck right to the top of this modified area with a ton of good information to read through.

NUKEM-10

Mid arm and short arm are the same thing for a JK. What year model do you have? and what model is it?