Jeep Enthusiast Forums banner

Next stage in build, 40s on a 3" OME LT lift, 1" BL, & flat flares

43105 Views 76 Replies 38 Participants Last post by  zjilla
Edit: This is how it ended up:

  • 3.25" front and rear extended bumpstops.
  • Trimming at the front and rear edges of each fender well
  • Trimming of front frame crossmember ends
  • Flat flares and 1" body lift
  • Move rear axle back 0.75" (includes relocation of frame side trackbar bracket, rear swaybar mount relocation, rear brakeline relocation, aftermarket driveshaft, rear lower coil perch correction)
  • HD rear tire carrier capable of 135 lbs spare
  • 3" net backspaced wheels
  • Longer bolts to uses as custom steering stops
  • Hydro assist steering
  • HD drag link and tie rod
  • Front axle truss, sleeves and gussets
  • Dynatrac ball joints
  • Front and rear chromoly axle shafts

I did end up having to rebuild/repair my rear axle multiple times with 40s. First, I broke a rear Rubi locker. Second, I blew a rear ring and pinion. Third, I bent both my rear chromoly axle shafts. So, I eventually upgraded to front and rear Currie Rock Jock 60s.

Original post:

National Tire & Wheel has a special purchase on 40x13.50R17 Xterrains for $300 each with total shipping of $69.95--although they are running free shipping occasionally on weekends.

$1565.95 for 5 40" tires shipped was too good a deal to pass up. I have my 37" KM2s on Blackrock 909s for winter wheeling and to save my Walker Evans Beadlocks from winter chemicals & salt. I was looking for a screaming deal on tires to run during the summer. Here is the link:

40" Special Purchase Tires @ NTW

I had seen and corresponded with Co4Lo who ran 40s on a 3.5" RK lift with flat steel flares. He inspired some confidence for me. So, I made the jump.

Time to report progress and findings.

My local 4x4 shop is custom fabricating a rear bumper/tire carrier for me. It should be done in a week or so. So, I will post pics then. Until then, I have no rear bumper or spare.

Also, I haven't posted a pic of my River Raider cage:

Anyway, here are the before pics on 37" KM2s:

With the new 40s, the wheel with the most balancing weight required 10 oz. The rest required much less:

Least weight (less than 2 oz.):

Most weight not including the spare (8.5 oz.):

So, the first thing I did was increase the length of my front bumpstops from 0.75" to 2" using JKS adjustable bumpstops. I could have reinstalled my TF front extended bumpstops from my 2.5" BB, but it was much faster to use the JKS ones. 2" extended front bumpstops on a 3" lift leaves about 3" of up travel before the stop would be fully compressed:

Next, my PureJeep Crawler Stubby Front Winch Bumper would have been in the way. So, I converted the bumper to a PureJeep Bare Bonez Crawler bumper (the before is above).

See less See more
1 - 20 of 77 Posts
Next, after installing the tires/wheels I took out the sawsall to do some cutting in the rear fender well. I had already folded over the pinch seam at the front of the rear fender well with a BFH. (The before is above.)

Next, since I had the sawsall out, I decided to cut the ends of the front cross member that stick out under the bumper.

Next, it was time to adjust the steering stops. Unfortuneately, my WE beadlocks have 4.5" backspacing. So, I needed to go to the hardware store and buy longer bolts to have longer steering stops to avoid rubbing on the frame. It did cut down my turning radius some, but it isn't as bad as our dually truck.

Here is a side view:

Here is a front view:

Next, it was time to test the rear bumpstop and axle placement. With no rear bumper or spare, and the extended rear bumpstops that came with my TF BB there would be about 5" of rear travel before the bumpstop would be fully compressed.

I am still running stock rear lower control arms with JKS rear uppers that I bought 2nd hand. I purchased but have not yet installed new rear lower Currie arms to move the axle back. Looks like I will need to move it back about 1/2" to 1" and either cut more of the pinch seam or bumpstop more. I stopped when the rear tire started rubbing good, but the front had much more room to go before the front bumpstops touched:

See less See more
Holy 40s batman!
looks great!
Wow you got some big tires :eek:

Lookin good! Nice work.

I am glad to see how well your lift and tire setup are working together. You are giving me confidence for my build coming soon. :D
Thanks guys.

We drove it on the freeway today, and it did fine.

At 75 mph, I am running about 2850 rpm with the 40s and 5.13s and my 6 speed.

I also did some more cutting today in the rear fender well.

I didn't get around to installing the new rear lower arms to stretch it about 1/2" to 1", but should have time to do that tomorrow night.
More progress.

Yesterday, I installed Currie rear lower control arms set at 0.75" longer than stock and Rock Krawler lower spring perch wedges to move my axle back in the fender well and adjust the rear spring angles caused by the stretch.

The RK wedges effectively lifted the back by about 1/2". So, I installed 1/2" Teraflex front coil spacers as well.

I am cutting 6, 1/4" thick steel plates in the shape of the stock axle bumpstop pads with matching drilled holes for bolts. I will use the plates to extend my Teraflex rear lower bumpstops somewhere between 1/4" and 3/4" by sandwiching 1 or more of the plates under each of the 2 Teraflex bumpstops.

I'll drill a hole through the top of each Teraflex bumpstop so I can fit a longer attachment bolt through it.

I hope to have my rear bumper by the end of the week. The addition of the rear bumper and my spare should help level out my jeep.

Here are some more pics:

Before longer wheelbase:


Rock Krawler wedges:

Currie lower control arms (in order for both the lowers to be the exact same length, I had to leave the zirk fitting down on one side):

See less See more
I run my zirk fittings down anyways... Makes it easier to get to them.. Is that bad? I guess it does make it easier for rocks to access them too:rofl: But I havent had any trouble out of em yet.
nice build bro. good to see someone that can do it right without buying the all the high dollor kits.:cheers2:
Awsome Jeep... one day when I'm big I want a Jeep like that.
Very nice rig! :2thumbsup: Inspiring.

In your profile, it says you upgraded axles to chromoly shafts. :cool: I looked and couldn't tell if you stayed with 30 front & 32 rear spline axles (stock e-locker) or did you change up to the 35 spline chromoly (and use the ARB locker)? 40" wheels on D44 is very nice.

I'm running 35" wheels & don't think I could get into Jeep with 40" wheels! :laugh:
Very nice rig! :2thumbsup: Inspiring.

In your profile, it says you upgraded axles to chromoly shafts. :cool: I looked and couldn't tell if you stayed with 30 front & 32 rear spline axles (stock e-locker) or did you change up to the 35 spline chromoly (and use the ARB locker)? 40" wheels on D44 is very nice.

I'm running 35" wheels & don't think I could get into Jeep with 40" wheels! :laugh:
Still running stock Rubi lockers with chromoly shafts (Superior and Alloy USA) with stock spline counts.
looks awesome man :drool:
1 - 20 of 77 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.