[Mikeyboy_esq]

Mikeyboy_esq, how many miles on axles? Mine had 6200.

Currently, I have a little over 1,000 miles on my RZR (almost all of which were racked up in XC races).

 

[RZR_Joe]

@Mikeyboy_esq You asked the same question on the Turbo group on Facebook, some interesting answers you received

 

[shilo020]

I am not sure there is enough incidence of axles breaking at the threads to determine causality. If all the cars come from factory at 180ft/lbs and that torque is causing stress there should be lots of failures there. Only a few of us on this forum are reporting this.

 

[shilo020]

RZR Joe, you don’t just count the ugga duggas on your Milwaukee?

 

[shilo020]

I think though that the most likely cause is the nut backing off a little, flattening or breaking the cotter pin. A little play is introduced wheel to hub stressing the axle until it breaks. I don’t think less torque is the solution.

(I meant play hub to axle and carrier)

 

[shilo020]

 

[yamahaSHO]

When I removed my OEM axles, I was able to break the nuts loose with my Snap On 3/8" electric impact. It is not capable of breaking anything loose at 180 ft/lbs... Maybe 120 ft/lbs on a fresh battery.

 

[dafish]

The torque amount is oft discussed. Poo has not backed off on 180, and it's been something like 5 years now, so... I don't know the alloy, so we're not going to be able to tell what the "correct" stretch for that nut is. I can say I'm going to use 155-160 NET moving forward instead if 180 and apply some locktite.

As I'm sure you know, the 180 is a dry thread spec. Locktite recommends a 20% reduction in torque when using their thread locker to correct. Since I want an NET 160 max with a threadlocker, I'm going to set my wrench to 125 and tighten to the next hole. I expect to get an equivalent of 160 or so, and I hope to stop nut creep dead.

FYI, the right side is alleged to be the most common, for we tend to turn more sharply to the right, and the load unload of that turn tends to loosen the nut more (as I recall. Read the many threads on this).

I can't help but note the break is at the thread beginning. Right where the most torque from the nut is being applied. Granted its also where a lot of stress from any other g force presents, but this is the place that takes all that load plus the nut torque.

Finally, If I was experiencing axle breaks at all while I was running at speed I'd insta pull that shit off and put on stronger axles. I don't know enough about it, but I'd lean towards a set of 300M axles from somebody that was carefully heat treating them and then I'd have them cryo'd.

Unless of coorse somebody is making a larger splined hub that accepts Poo wheels and brakes, for that's the best of all possible answers.

 

[Pro4driver]

When I removed my OEM axles, I was able to break the nuts loose with my Snap On 3/8" electric impact. It is not capable of breaking anything loose at 180 ft/lbs... Maybe 120 ft/lbs on a fresh battery.

I think you may have had this happen because the axle has already stretched and starting to weaken/break. Just a matter of time. Lot of people having the issue. Most are abusing the rig and it happens after warranty so they just replace and repeat and never report anything. Doesn't seem to matter who makes the axle, but I'm sure some are better than others. Be nice to see SATV make one with slightly larger threads and additional threads on the nuts for more grip at less torque spec. I don't expect to have any more issues after all the research and testing we did on TRE and RS1. It should never happen.

 

[shilo020]

Pro4driver. I just read your threads. Good stuff. I couldn’t find much posting about this Jan 2020 when I broke mine. And as you see was the right rear.

 

[RZR_Joe]

RZR Joe, you don’t just count the ugga duggas on your Milwaukee?

Nah, I use a DeWalt

Since they are electric the correct unit of measure is rat-a-tats

 

[RZR_Joe]

I am not sure there is enough incidence of axles breaking at the threads to determine causality

I think you are correct sir. What I find interesting is it has happened to the person twice. That leads me to believe it's something to do with the torquing process.

 

[RG1]

Same thing happened to me on my old wildcat. Held on by caliper. Then installed a rhino axle. Sold machine. Then it happened to the guy who bought it. I also agree 180 seems ridiculous. The cotter should prevent back out. I’d agree with Joe. 120 seems far more reasonable.

 

[craigstumph]

Axle fatigue causes a lot of problems such as this. The end of the threads is a stress riser that after some time breaks because the stress from use starts a crack and it eventually breaks from riding. Axles with less of an abrupt termination last longer (smoother transitions). Axle material is also a factor. Tight is better than loose. Any amount of torque that keeps the axle tight in the hub is OK. I have never torqued an axle to 180. Run the nut up snug with an impact gun (snug not impacted). Tighten until the cotter pin goes in. This should work fine.

Anything that causes wheel spin and then contact with traction increases stress. Jumping and whoops are a couple things that come to mind. Run the best axles you can afford. Not all axles are stress relieved and have the ductility and strength to hold up. I hope that helps.

 

[yamahaSHO]

I think you may have had this happen because the axle has already stretched and starting to weaken/break. Just a matter of time. Lot of people having the issue. Most are abusing the rig and it happens after warranty so they just replace and repeat and never report anything. Doesn't seem to matter who makes the axle, but I'm sure some are better than others. Be nice to see SATV make one with slightly larger threads and additional threads on the nuts for more grip at less torque spec. I don't expect to have any more issues after all the research and testing we did on TRE and RS1. It should never happen.

I've removed a lot of axles in my time of racing and not once has that ever been a thing. Axles shouldn't just break like this. This part of the axle is basically a bolt through an inner race.

The only time I've broken an axle like this on a race car is when unloading it and then giving it 600-900 ft/lbs of torque on a lot of traction and considerably more weight. Once upgraded to beefy axles, we break the joints instead.

As I'm sure you know, the 180 is a dry thread spec. Locktite recommends a 20% reduction in torque when using their thread locker to correct. Since I want an NET 160 max with a threadlocker, I'm going to set my wrench to 125 and tighten to the next hole. I expect to get an equivalent of 160 or so, and I hope to stop nut creep dead.

Additionally, torque should go down on used threads vs new as the friction of the thread will be less.

 

[shilo020]

I re read all the posts I could find on this subject. We still have no evidence that the 180ft/lbs torque is causing the problem. Much more likely that nut loosening (even with the cotter pin) is causing the increased stress. If that is the case, lowering the torque valve may increase the risk. The large strong pin Pro4driver mentioned might be a good idea. Whenever I have had to help fix a broken axle at CV joint the pin was very difficult to get out making me think the nuts are backing off.

 

[RZR_Joe]

The nut can't back off enough with the cotter pin in place to change the torque rating any significant amount.

 

[shilo020]

My XP1000 has front 5.1+0.9 wheels plus 1” spacers. The OP has 4+3. Dafish and Pro4driver post in TRE. Presumably their rear wheels are also moving the center of the tire wider. This may be causing more stress on the axle at the treads.

 

[shilo020]

The nut can't back off enough with the cotter pin in place to change the torque rating any significant amount.

The pins could deform or break. We don’t know if the pins are even still there when this happens.

 

[rzrhle]

So what criteria determines the amount of torque to use for a specific application? That 180ft/lbs “feels” and “seems” to be a little much but unless it’s just a flat out error in the specs, I don’t think Polaris just pulled it out of their a$$.

I’m sure there are standardizations of how torque settings are determined, but then again sometimes things on paper do not work out exactly how it should in real world application.

Any engineers in house to shed some light on the subject?