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If i run 35s (315/75/16) on my front d30 axle, what do i need? Not interested in any crazy rock crawling, mainly eazy to moderate trails, beach driving. I'm running 33s (285/75/16) now and I'm confused on how the 2" extra tire affects the axle.
 

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It's not that you gross some magic size of tire and then the axle blows up. It's that as you increase tire size generally the weight goes up. That's what puts stress on the axle. Weight will vary based on what tire type and rim you use as well. My tire plus rim weighs 91lbs and that's with a C range tire. The weight would increase if I had a D or E range tire.
 

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Im in the same boat with 3.73s. My tire combo weighs 96 lbs each. From what your describing as far as use is pretty much what I plan as well. I would say at the least gusset the top Cs and keep an eye on ball joints/ tie rod ends. These newer generation Dana 30s aren't as fragile as others think. As long as you're not bouncing off the red line and forcing yourself over stuff and take it easy and slow on the trails you describe you'll be ok.
 

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If i run 35s (315/75/16) on my front d30 axle, what do i need? Not interested in any crazy rock crawling, mainly eazy to moderate trails, beach driving. I'm running 33s (285/75/16) now and I'm confused on how the 2" extra tire affects the axle.
The effect is long term, not immediate. Hard wheeling just speeds up the process.

The problem is that the axle is weak. The thin wall tubes and small inner C can't take the stress and slowly bend over time, even with stock tires.

I'd highly recommend reinforcing both the tubes (with sleeves or a truss) and the inner C's. I'd recommend this even if you don't wheel hard. 35's are heavy and can cause premature bending of the axle even if you never leave the pavement.

I did the Artec kit. It's well designed and has held up great over the last couple of years.
 

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I just don't see or haven't seen any axles bending under daily driven Jeeps with 35s. If someone has any pics or info of this I would like to see it before I decide to spend money on doing anything more than gussets ( light wheeling included).
 

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There is little difference in the factory D30 and D44. They use the same C's, axle tubes, suspension and shock mounts. The difference is really the internal axle shafts, gears and gear housing. Both the factory D30 and D44 have similar problems when tire sizes get around the 35+ and tend to break/bend the same parts.

The strength advantage with the factory D44 comes when running a locker. This is do to the thicker internal axle shaft and larger gears.

Both the factory D30 and D44 need additional strengthening
if one is going to use them hard and often off road.

Photo of factory D44 broken axle tube. DeathValley, race track road.
 

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Another photo of same Jeep with broken D44. Notice the tire is smaller than a 35. It was a similar size to a factory tire. This Jeep was a 2013 JKUR and had under 18k on the odometer.
 

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If I were to take a guess judging by that number 78 under the headlamp this Jeep might be some sort of a trainer or constant abuse type rental jeep for offroading. The smaller tires are a bit concerning though.
 

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If I were to take a guess judging by that number 78 under the headlamp this Jeep might be some sort of a trainer or constant abuse type rental jeep for offroading. The smaller tires are a bit concerning though.
It was a rental Jeep (2013JKUR). The photo was take by me in spring of 2014. It was a low mileage Jeep and overall in good condition. A rental company rep that arrived on sight to "rescue" the Jeep said this was the third that month to break an axle tube.

The "Race Track" road at that time was the worst "wash board" road I had been on ever and I have been on some bad ones. This Jeep was one of FIVE vehicles we passed with either a flat tire or something broken. I had to stop pull our QDs and air down to make the 40ish mile round trip to the "Race Track" livable.

The photo just shows why sleeves are needed regardless if factory D30 or D44 if one is going to drive their Jeep hard and without care as this one was sure to have been. Had this Jeep been disconnected and aired down it would
have had a much longer axle tube life.
 

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I just don't see or haven't seen any axles bending under daily driven Jeeps with 35s. If someone has any pics or info of this I would like to see it before I decide to spend money on doing anything more than gussets ( light wheeling included).
It has been well documented over the years on this forum
 

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If I were to take a guess judging by that number 78 under the headlamp this Jeep might be some sort of a trainer or constant abuse type rental jeep for offroading. The smaller tires are a bit concerning though.
While I am not a huge advocate for dumping a lot of money into the D30; it makes sense to sleeve the axle while you're getting the labor done for gussets. Both are good insurance.
 

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It has been well documented over the years on this forum
Well if it's well documented then it shouldn't be that hard to prove a "Mostly street" driven JK with 35s that broke. I'm not talking about weekend warriors or anything like that. Just a 95% road Jeep that does light fire trails like the OP stated.
 

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Well, you dont "have" to do anything to your Jeep with 35s, or 37s, or any size tire for that matter. Would a prudent person spend a little bit of cash to reinforce known weak points in their setup? Sure - you spent a lot of money just buying your rig. A pair of gussets (what $50?), or a sleeve setup (Synergys I believe with the sleeve and gussets is around $200), or a full blown front truss and gusset setup (Artecs is like $300) is relatively cheap. And chances are it may mean the difference between your rig driving home or taking a flatbed tow trip. Is it fool proof? No, nothing is. But could it make a difference? Absolutely. Just like any other "insurance", it isnt worth it until you need it. So do you feel lucky-or not-is the question.

Not directing it specifically to any of the posters in this thread, but I love posts that start with "Do I really need to spend the money to regear/truss/[insert prudent mod here]? A 50 inch light bar, bigger tires, and a new stereo just look way cooler and I would rather do those instead if I dont reallllllly have to do the other stuff. K thanks bye."
 

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Well if it's well documented then it shouldn't be that hard to prove a "Mostly street" driven JK with 35s that broke. I'm not talking about weekend warriors or anything like that. Just a 95% road Jeep that does light fire trails like the OP stated.
In the 5 years or so that I have been on this forum I can remember several threads of failures, even on jeeps that never left the pavement. Thats not saying they all do it but it happens.
 

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Anything can happen. But a D44 will bend just as easy as a D30 its the same physical structure. C's, tubes, all the same.

C gussets are cheap.
Sleeve kits are cheap.
Trusses are cheap.
Labor to disassemble front diff and have parts welded properly then reassembled.. Not so cheap.
If you can weld and do all the work yourself it is affordable. To anyone that has to pay, Not.
 
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