37s on 392xr. Lift needed?

hardhat

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2021 Sarge 392xr
Can you wheel with 37s on xr package using stock rims without rubbing?
Haven't seen this definitively answered

37x12.5 km2
Or ko2 for on road
 
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My dilemma is that I don't want to replace the front driveshaft. I prefer the maintenance free Rzeppa CV joint on the transfer case to the double carden joint on aftermarket driveshafts. The double carden joint is not a true CV joint. Both ends do spin at the same speed, but the intermediate part of the shaft is speeding up and slowing down throughout every revolution transferring some inertial energy to the driveline constantly. This can introduce vibrations in some cases. I especially don't want to do this if you have to grease the double carden joint (which would require skid plate removal)

I also don't like the high driveshaft angle at the transfer case. On my JK with 4.5 aev lift, the angle is quite extreme and I've had to replace my CV joint twice in 80k miles (not too bad). Maybe driveline angles are better on the JL, but on the JK the engine and transmission are sloped downwards which makes the front driveshaft connection point upwards from the transfer case (which sits higher than front axle). This creates a steep angle in the front driveshaft at the transfer case that gets worse the higher the lift or the more downtravel on the suspension. Geometry correction brackets on the front axle can help with this.

The stock driveshaft should be completely trouble free at stock height.

Not wild about replacing fenders as I like the look of the stock fenders, but does anyone know if Metalcloak Overland fenders would let you run 37's with no lift and no rubbing even when wheeling?
 
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37.5 x 12, no lift. No rubbing but havent pushed it off road yet.

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Sounds like you can run 37s with no modifications as long as you are mall crawling. However, if you plan to go off road, you may experience rubbing.
 
Are the suspensions on the non XR 392 and the XR392 the same?

I don’t have the XR package on my 392, but I did try 37x12.50s on stock wheels and no lift. I did use 1.75inch spidertraxx wheel spacers. I put the spacers on before the tires.

From my experience and assuming the suspensions are the same, you can safely run 37s on the road with setup I described above. With sway bars disconnected (photos 1 and 2) the front has plenty of clearance, however at full stuff the rear does make contact with the rear inner fender. Once taken off road (photo 3), the tire will make contact and the knobs will pull the inner fender liner out. When this occurred on a very mild trail, my 3 year old son asked why the Jeep kept farting.

My solution was to add Fishbone Offroad 3/4 inch spring spacers in the front and rear. I also added Teraflex Performance Bumpstops and 2 inches of bumpstop from Metalcloak in the rear only. I have tested this Offroad since then and everything has cleared. Completed badge trails 26 and 16 at Windrock and hit some other local spots with no clearance issues at all.

On the road this setup has worked great. I drove from southeast TN to Sarasota FL and back in 48 hours and it handled fine the entire way - just drank a lot of fuel!
 

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Thanks for the detailed writeup
Are the suspensions on the non XR 392 and the XR392 the same?

I don’t have the XR package on my 392, but I did try 37x12.50s on stock wheels and no lift. I did use 1.75inch spidertraxx wheel spacers. I put the spacers on before the tires.

From my experience and assuming the suspensions are the same, you can safely run 37s on the road with setup I described above. With sway bars disconnected (photos 1 and 2) the front has plenty of clearance, however at full stuff the rear does make contact with the rear inner fender. Once taken off road (photo 3), the tire will make contact and the knobs will pull the inner fender liner out. When this occurred on a very mild trail, my 3 year old son asked why the Jeep kept farting.

My solution was to add Fishbone Offroad 3/4 inch spring spacers in the front and rear. I also added Teraflex Performance Bumpstops and 2 inches of bumpstop from Metalcloak in the rear only. I have tested this Offroad since then and everything has cleared. Completed badge trails 26 and 16 at Windrock and hit some other local spots with no clearance issues at all.

On the road this setup has worked great. I drove from southeast TN to Sarasota FL and back in 48 hours and it handled fine the entire way - just drank a lot of fuel!
Thanks for the detailed writeup. I think the suspensions are pretty much same other than shocks, but not positive. I am thinking that metalcloak overland fenders might be the answer to running 37s without having to touch the suspension and still giving oem levels of articulation offroad. Would prefer to not have to add additional bumpstops to limit uptravel. I'm thinking the fenders would allow the uptravel. Will call metalcloak and see if they can tell me for sure. They used to advertise that you could run 37s with no lift on stock JK with their overline fenders which just seems crazy.
 
No lift and 37’s will rub when articulating. As for steering, the factor of wheels set up will determine that more than a lift.
 
I have 37 x 12.50 Nitto Ridge Grappler tires on mine with stock wheels and 1.75" Teraflex wheel spacers. I also have a Metalcloak 3.5" Gamechanger lift with two additional spacers under the rear springs as I like a slight rake with the rear a little higher than the front. On roads and easy trails there is no rubbing. However, on extreme articulation in certain circumstances I get a little rubbing but nothing severe.
 
37s on a 2.5 Clayton Off-road lift. Overland +. Nitto Ridge Grapplers. Fox 2.5 DSCs with reservoirs.
 

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Are the suspensions on the non XR 392 and the XR392 the same?

I don’t have the XR package on my 392, but I did try 37x12.50s on stock wheels and no lift. I did use 1.75inch spidertraxx wheel spacers. I put the spacers on before the tires.

From my experience and assuming the suspensions are the same, you can safely run 37s on the road with setup I described above. With sway bars disconnected (photos 1 and 2) the front has plenty of clearance, however at full stuff the rear does make contact with the rear inner fender. Once taken off road (photo 3), the tire will make contact and the knobs will pull the inner fender liner out. When this occurred on a very mild trail, my 3 year old son asked why the Jeep kept farting.

My solution was to add Fishbone Offroad 3/4 inch spring spacers in the front and rear. I also added Teraflex Performance Bumpstops and 2 inches of bumpstop from Metalcloak in the rear only. I have tested this Offroad since then and everything has cleared. Completed badge trails 26 and 16 at Windrock and hit some other local spots with no clearance issues at all.

On the road this setup has worked great. I drove from southeast TN to Sarasota FL and back in 48 hours and it handled fine the entire way - just drank a lot of fuel!
So this solution works? No rubbing on stock suspension? Any impaired ride quality?
 
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