[MGrobe]

Originally Posted by jeepfury

If I recall correctly a well known club member of Terra Jeep died not too long ago because he tried to limp home his rig. He left the outer shaft out of the bearing; it failed came off then rolled his jeep. I think he was coming home from the baldands.

Yep. I remember reading about that. If you didn't know before (which I didn't always know this until 5 years ago) the front axle is semi-floating and requires the stub shaft to help hold the weight of the vehicle. As you can see from Heavy's photo above the uni-hub are two pieces pressed together. Eventually that pressing is going to fail. A number of Jeepers have made this mistake in the past, but have gotten very lucky that it failed quickly and at low speeds.

[XJohnnyC]

I had some cheap eBay specials do that. As soon as I took off the calipers and rotors, they just fell apart onto the ground.

Now I only use the Timkens and also carry spare outers.

[AZ Jeff]

Originally Posted by jeepfury

If I recall correctly a well known club member of Terra Jeep died not too long ago because he tried to limp home his rig. He left the outer shaft out of the bearing; it failed came off then rolled his jeep. I think he was coming home from the baldands.

Leaving the stub axle out of the unit bearing is just ASKING for bearing separation. The axle (and being torqued to spec.) is how the bearings get their correct preload. The bearings should NEVER be used without the stub axle being in place and torqued properly.

[Bryson]

Some of you might be wondering why the Jeep bearings fail in the first place. It's because all of the ones that I've seen utilize a ball bearing design. Ball bearings simply do not have a high thrust load capability.

Angled roller bearings however, are much more common in a wheel bearing design because they are much more effective at controlling high thrust loads in addition to normal radial load.

I'm not sure if the timkens are roller or ball?

[Jeepernick]

very good point for sure

but they were also designed to run 195/75-15 tires too

35s are much bigger adding much stress to a "weak" design. weak for 35s but good enough for 195s

[Bryson]

Originally Posted by Jeepernick

very good point for sure

but they were also designed to run 195/75-15 tires too

35s are much bigger adding much stress to a "weak" design. weak for 35s but good enough for 195s

Definetly a valid point. Upping the tire size doesn't help anything, but if they would have utilized a roller bearing style in the first place, people would be able to run 37s+ with no problem.

Ball bearings + wheel bearing application =

I also think this is one of the main causes of front end vibrations as well in almost every stock D30 application.

[shmoken875]

Originally Posted by Bryson

Some of you might be wondering why the Jeep bearings fail in the first place. It's because all of the ones that I've seen utilize a ball bearing design. Ball bearings simply do not have a high thrust load capability.

Angled roller bearings however, are much more common in a wheel bearing design because they are much more effective at controlling high thrust loads in addition to normal radial load.

I'm not sure if the timkens are roller or ball?

edited to remove mis-information

[LEAD_NOT_FOLLOW]

Originally Posted by jeepfury

If I recall correctly a well known club member of Terra Jeep died not too long ago because he tried to limp home his rig. He left the outer shaft out of the bearing; it failed came off then rolled his jeep. I think he was coming home from the baldands.

Yes this is correct. He broke his stub shaft and everyone kept quite about him running without the shaft that he was with. The hub broke while he was doing 60 on the highway and he rolled his wrangler several times. It killed him. His father was riding shotgun and made it. He left a wife and 2 kids behind.

I was there that same weekend and saw him about 4 hours prior on the trail where he broke.

We had a fellow member that same weekend break his locker and we had to remove the shaft to allow the locker to spin freely to get back to camp. We were about 50 feet from the campsite and it let loose. They were only driving about 5MPH and it broke the knuckle; I can only imagine what it looked like letting loose at 60...





As stated above, DO NOT DRIVE WITHOUT A SHAFT IN IT!

[Jeepernick]

I have driven once without the shaft in... and had to wheel it pretty hard to get out of where I broke the shaft.


and then drove 20miles home... avg of 45+ mph

wow I feel lucky...

glad I carry spares, both hubs and axles

[ktmracer419]

Originally Posted by iwishihad1

i consider you doing pretty good for a hub a year. im on locked 35s. and ill be putting on my 6th hub tomarrow. im pretty hard on the poor little 30 though

what do you torque the axle nut to?

[lifted92xj]

your 6th hub..you might want to look into something a little stronger..and yeah taking the shaft out is a killer..luckly when it happened to me my brakes kept my wheel from falling off

[SmrtJustin]

Originally Posted by ktmracer419

what do you torque the axle nut to?

175 ft-lbs.

[HeavyMetal]

he was asking what the kid was doing, not what you should do in general

[iwishihad1]

yea..i was doing it to whatever spec was. im building a 44 front right now so im not worried about it, and that will be my "stronger" option. ive got hubs from advance with a lifetime warranty so i really dont even worry about it

[tangofox007]

Originally Posted by shmoken875

they're all [xj units] ball, it'd be nice if somebody made a roller bearing though, get to it and get rich!

Not all XJ's use ball bearings. The AMC versions used tapered roller bearings.

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=SKF&MfrPartNumber=JLM60 3048F&PartType=184&PTSet=A