kahnah

Ive been looking through the forum and im sure that there is a thread somewhere that answers my questions but i have yet to find it.

I am interested in installing a set of 37 inch tires on my 2007 wrangler X. I am aware that it is a good idea to re gear to 5:13 or 5:38 if im correct.


From what i have heard, from a local jeep shop, when upgrading to 35 and larger tires the stock axles can camber up. Should i install axle sleeves to strengthen up the stock axles or should the axles be fine without it.

After re gearing are the stock drive shafts strong enough to turn those massive tires?

When re gearing there are programers to reset the revs, speedo, and shift time in the auto, does driving a standard need a certain programer or a programer at all? Also if you had to choose a programmer which would be a good choice.

And last question is what is the average gas mileage after re gearing and installing 37s?

Any advice is greatly appreciated, but im looking for jeepers that have 37's.

Thank you for your time

silverbackjk

your x has a front dana 30 axle and if you are going to run 37's you should get gussets and sleeves. I have EVO sleeves and gussets installed. Here is the link.


http://www.offroadevolution.com/stor...VO-AXLEGUSSETS

http://www.offroadevolution.com/stor...prod=EVO-44MAG

duffyboby

First of all, you are correct to say that re-gear is a must. I think its 5.38 if you have an auto and 5.13 if its a stick but thats a choice youll have to make. Then you will certainly have to change at least your front drive shaft because when running a big lift like one to run 37s, the stock shaft will catch on the tranny skid plate and it will rip and break but they are strong enough for road driving.. Then your front axle shafts wont hold up very long you must have to change those also. Evo sleeve are also a good idea. Yes there are programmers out there that do all this and even give you more performance or fuel economy. I would recomment the superchip flashpack. For gas mileage, i heard many people say they where getting around 12-14 mpg... Sorry lol. Finally, i have no clue about the caster angle with the big tires, i cant help you with that. Good luck with your built!

SH0RTBUS

Everyone seems to add gussets and sleeves when going to 37s, but I think the weakest link is going to be your R&P gears when running a D30. Especially if you go with 5.13s. No way to fix that without going up to a D44.

Tvernon

This was not mentioned in your thread; is your jeep a pavement princess, or are you going to take it out and seriously play with it?

If it is a road queen then gusset the hell out that D30 and upgrade all of the internals to 35 spline if you can. Sleeve the housing and you will probably be okay.
However, there is more to consider. In your case you will have to stick with 5.13 ring and pinion. To my knowledge there isn't a company that makes a 5.38 for the D30, perhaps there are, but that pinion gear would be so small that I would personally worry about stripping it out again and again. You will also need to consider the steering geometry. 3" is about as high as you can go without correcting the steering and I assume you will be going higher than that. Rock Krawler among others makes a quality steering correction kit. Look those up. As for tuners the superchips flashpaq is a great product. I have nothing but good things to say about them from my own personal experiences. The new dash mounted, android powered monitoring system looks really cool; pricey, but really cool. Your drive shafts will need to be replaced if you go any higher than 3" as well. Strength is not really the problem, the problem is that in order to maintain proper caster you will need to return the axle positions back to stock. To do this, you will need adjustable upper and lower control arms both front and rear. Long arms would be better for anything above 4". I honestly believe this is what your mechanic was talking about when he said "caster up". Aside from stripping all of the brackets off of the axle and re-doing them from the ground up to adjust the pinion angle, there isn't another way to correct the caster other than control arms. But to the point, correcting the caster curve will mean your drive shafts are too short. That is why they need to be replaced. Keep in mind, all of these things are if you're rig is a mall crawler and nothing more. If you're going to be off-roading at all then that stock front turd has to go and the list gets much longer much faster.

Good luck on your build,

Tyler

P.S.- Your gas millage is going to suck... at best. There really isn't any way to sugar coat it.

Delux2769

OR you can do what my poor ass is going to do.

Sleeve and Gusset, stock 3.21 gears because I can't drop a grand on new gears, stock wheels, already have RC wheel spacers, cut my fenders into Flat Fenders, TF 1.5" leveling kit.

That will get 37" tires rolling under me. I don't have to worry about hills. My Jeep's a "Mall Crawler" I don't take it off roading, other than gravel roads. I can't afford to fix stuff when it breaks off roading.

You do not HAVE to have new gears. You do not NEED a new front driveshaft if you do not flex. You do not NEED new control arms.

Larger tires do not affect your geometry. The lifts that are used to accommodate them do.

Zpack

You are going to be miserable with 37's and 3.21's especially if you have an auto. I hated my 4.10's and 35's! Regearing has been my best mod so far and its not that expensive

Delux2769

I didn't mind 3.21's and standard with 37"s. And anyone who says regearing isn't expensive has forgotten what it's like to be a college student with a horrid paying student job.

jkambulance

Alrighty here's my question. I have a 2010 rubicon unlimited. I'm looking at a teraflex 4" long arm lift kit and it was recommended to me that it would be a good idea to get some EVO coilovers. What is the purpose of the coilovers, what else do I need to do to get 37's under there, is there anything else I'm going to need, and will somebody please explain bump steering?! Lol thanks everybody.

Btw I do plan to regear to 5.38 since it is an auto what all is need for that?

samhardy2008

showin some love for us broke kids .....dude im the same way...i cant afford to drive the shit out of mine offroad...so i play when i can and dream about getting 40s someday and having a pr44 up front and a d60 out back...ah yes thatd be sweet lol