BFG KO2 39x13.5xR17 on UD 44 Axles

[FreedomFur]

Anyone running the 39” KO2 on Dana 44 or UD Dana 44 axles? I have an 2022 Rubi with the XR package (supposedly beefier Dana 44 axles) and will have the clearance to run with the fender chop/liners and maybe a lift. All tires typically run 0.5-1.0” small than the sidewall measurement and the 39” KO2s are still lighter than most 37” tires. Is the increase from a 37” KO2 to a 39” KO2 going to spell a quick disaster to the axles?

I am not running Moab or the Rubi trails. Moderate - hard offroading in NH with some rock crawling, mud pits, etc.

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[BJACK]

I'm running 39" KO2's on D44's. I've done some moderate offloading and no problems yet. I measured them at 38" tall and 80lbs each.

 

[Some Random Guy]

I have the 39” KM3’s on the stock D44, but Yukon 5.13 gears. Not sure if that helps.
The axle isn’t an issue yet. I’m probably a “moderate” offroader. I don’t travel the country, but I try anything locally.
I did have to trim a lot on the body, not just a fender chop. I’m eventually buying longer CA’s to push the axle further back, I’m on 3” of bumpstop right now.

 

[FreedomFur]

I have the 39” KM3’s on the stock D44, but Yukon 5.13 gears. Not sure if that helps.
The axle isn’t an issue yet. I’m probably a “moderate” offroader. I don’t travel the country, but I try anything locally.
I did have to trim a lot on the body, not just a fender chop. I’m eventually buying longer CA’s to push the axle further back, I’m on 3” of bumpstop right now.

What did you have to trim on the body? I am going to be running Artec inner fenders on the front and rear.

Are you running a lift kit?

 

[Some Random Guy]

What did you have to trim on the body? I am going to be running Artec inner fenders on the front and rear.

Are you running a lift kit?

I have a true 3.5” lift (Maximus-3), but it uses stock control arms. Almost everyone I found had to trim or run more than 3” of bumpstop for the BFG 39’s.
I had to trim the forward part of the REAR wheel well, so just behind the rear doors. I still rub.

 

[FreedomFur]

I dont know if i have the guts to do that….

 

[Some Random Guy]

I dont know if i have the guts to do that….

I suspect adjustable control arms help. I’m planning to swap later, but I believe 37” is the limit on tires before the rear wheel well runs out of room. If it helps, the worst part is pulling the fenders, not actually cutting the body.

 

[FreedomFur]

I suspect adjustable control arms help. I’m planning to swap later, but I believe 37” is the limit on tires before the rear wheel well runs out of room. If it helps, the worst part is pulling the fenders, not actually cutting the body.

how much did you have to trim?

how many miles have you run the 39s off road?

 

[Some Random Guy]

how much did you have to trim?

how many miles have you run the 39s off road?

I didn’t measure, but I think it was 1/2” to 3/4”. Maybe 1”. I trimmed forward until the sheets of metal spread out to form the cab and then hit it with JB Weld.
Off road miles, probably only about 100. I rub when fully compressed post trim. I have about 3,000 on the tires.

 

[Bombout800]

I have 39 km2 with 3.5" rock Krawler no limits. VERY minimal rubbing on the rear pinch seam. Only the part of the fender/bumper that everyone removes is removed. No trimming of any kind. Can stuff the tire into the oem fender well liner all the way to the top and just hear the tires squeak on it. The punch seam doesn't get into the tire enough to cut the tread, so i haven't trimmed it.

 

[FreedomFur]

I have 39 km2 with 3.5" rock Krawler no limits. VERY minimal rubbing on the rear pinch seam. Only the part of the fender/bumper that everyone removes is removed. No trimming of any kind. Can stuff the tire into the oem fender well liner all the way to the top and just hear the tires squeak on it. The punch seam doesn't get into the tire enough to cut the tread, so i haven't trimmed it.

how are the axles holding up? What type of off-roading are you doing?

 

[jenzeee]

I got 39s KM3s on a 3.5' lift and arm kit, no problems (nor rubbing).

Will be switching to 39s KO2s and giving feedback.
But the KO2s should be overall a bit smaller due to lower thread.

 

[FreedomFur]

I got 39s KM3s on a 3.5' lift and arm kit, no problems (nor rubbing).

Will be switching to 39s KO2s and giving feedback.
But the KO2s should be overall a bit smaller due to lower thread.

did you truss or fusset the axles? Chrome moly shafts?

 

[OBJLU]

On an automatic I’d run these all day with chromo, truss and rcv, wouldn’t do it on a 6 speed because I’ve seen 3 rear ring and pinions blow on folks who drive a MT. I upgraded my rear to a Dana 60 to run these and the future 40’s

 

[jenzeee]

did you truss or fusset the axles? Chrome moly shafts?

Axles, shaft, gearing.. stock.

I got a 3'lift, flex control arms, and 39s.. basically that's it for performance.

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