[MGrobe]

Originally Posted by Bryson

That would be badass if thats true! If it works I would encourage anyone with larger tires on a late model D30 to swap out to this bearing. I'd consider it a cheap alternative to the warn conversion.

I'd also like to mention that the term they use "maintence-free" is kind of misleading. That really only means that the only way to replace the bearing is to replace the entire hub assembily, NOT that they will last longer.

Who ever decided to utilize a ball bearing with the late model jeeps should be shot dead.

You're dead-on regarding maintenance-free. And that brings up another question. I'm curious how often XJers with the earlier maintenance-capable setup actually pull things and grease. I know most trails in my 5-state area include mud holes to the point where often they're unavoidable on tight trails in the woods. I do appreciate the fact that the hubs I currently have can't have maintenance performed so that I don't have to feel obligated to pull them routinely and regrease everything. Pros and cons to both, although it would be nice to have the strength of the roller bearings though, that's for sure. Hopefully my setup won't give me any reason to want to switch in the future.

[Bryson]

Originally Posted by MGrobe

You're dead-on regarding maintenance-free. And that brings up another question. I'm curious how often XJers with the earlier maintenance-capable setup actually pull things and grease. I know most trails in my 5-state area include mud holes to the point where often they're unavoidable on tight trails in the woods. I do appreciate the fact that the hubs I currently have can't have maintenance performed so that I don't have to feel obligated to pull them routinely and regrease everything. Pros and cons to both, although it would be nice to have the strength of the roller bearings though, that's for sure. Hopefully my setup won't give me any reason to want to switch in the future.

That really all depends on how well they've designed the seals. I've never honestly seen it, so I'm not sure. But I know that a lot of taper bearing applications can go over 300,000 miles without the need for being repacked or rebuilt. There should never be a taper bearing in which requires you to constantly rebuild them, unless the seal doesn't do it's job effectively or it isn't torqued properlly.

IMHO, there is no contest between the two. I'm for the tapered roller bearings 100%.

[xjguy98]

I'm actually kinda interested in this too. Basically what I've read and understand is that I can use the older style (84-89) hubs on my '98 and just swap to the older style rotors? I'd rather rip the hubs apart every so often and grease the snot out of them then live worrying about when my "maintenenace-free" hub is gonna grenade on me....

[xjguy98]

Just checked out Rockauto for the specs between the two and here's what we got:

1989 1998
Flange Dia. 5.69 6.043
Bolt Circle 4.5 4.5
Bolt Size 1/220 1/220
Wheel Pilot Dia. 2.81 2.812
Brake Pilot Dia. 2.83 2.832
Flange Offset 1.81 2.133
Hub Pilot Dia. 3.75 3.942
Splines 27 27
Timken P/N 513107 513084


Not sure if it helps but I'm bored and felt inclined to up my post count

[tangofox007]

Originally Posted by MGrobe

You're dead-on regarding maintenance-free. And that brings up another question. I'm curious how often XJers with the earlier maintenance-capable setup actually pull things and grease.

I don't think the earlier versions are any more "maintenance-capable" than the later versions. They just use roller bearings instead of ball bearings; other than that, the concept is essentially the same, as far as I can tell.

Maybe you could explain why you believe that the later versions are "unitized" and the earlier ones are not.

[xjguy98]

you can't pull apart the newer bearings and grease them correct? Well.....you COULD but then they wouldn't go back together willingly right?

[88wagon]

I found this kit at napaonline. I selected front wheel bearings and it gave me an option for a front wheel bearing kit i'm not sure if this is correct or not but it looks like this kit will allow you to replace just the bearings. does this kit look correct its for a 2000 cherokee.

[Bryson]

Originally Posted by tangofox007

I don't think the earlier versions are any more "maintenance-capable" than the later versions. They just use roller bearings instead of ball bearings; other than that, the concept is essentially the same, as far as I can tell.

Maybe you could explain why you believe that the later versions are "unitized" and the earlier ones are not.

When it comes to this "maintenance" mumbo jumbo, It's really only trying to say that the earlier model bearings can be torn apart, and the bearings/races can be replaced without having to buy a complete hub assembily (as you do with the late models).

He mean't that the later models being "unitized" are essentially one-peice, where as the early models can be broken down and rebuilt.

[tangofox007]

Originally Posted by Bryson

When it comes to this "maintenance" mumbo jumbo, It's really only trying to say that the earlier model bearings can be torn apart, and the bearings/races can be replaced without having to buy a complete hub assembily (as you do with the late models).

If it makes anyone with a later model feel better, the earlier style hubs are not "maintainable" in the DIY sense. They don't quite "pull apart" in your hand. It takes an arbor press, adapters, hold-down plate and a bearing separator to get the things apart and back together again. And you can buy a new TImken assembly for less that you would have to pay someone to replace the bearings. (The bearings and seals will cost around $60, plus an hour of labor.)

[Matt Gertsch]

Originally Posted by tangofox007

If it makes anyone with a later model feel better, the earlier style hubs are not "maintainable" in the DIY sense. They don't quite "pull apart" in your hand. It takes an arbor press, adapters, hold-down plate and a bearing separator to get the things apart and back together again. And you can buy a new TImken assembly for less that you would have to pay someone to replace the bearings. (The bearings and seals will cost around $60, plus an hour of labor.)

The point of the swap would be to get the roller bearings rather than ball bearings.

[MGrobe]

Originally Posted by tangofox007

If it makes anyone with a later model feel better, the earlier style hubs are not "maintainable" in the DIY sense. They don't quite "pull apart" in your hand. It takes an arbor press, adapters, hold-down plate and a bearing separator to get the things apart and back together again. And you can buy a new TImken assembly for less that you would have to pay someone to replace the bearings. (The bearings and seals will cost around $60, plus an hour of labor.)

I'm glad you pursued this fully. Allow me to clarify my earlier thoughts/comments. All of my XJ buddies have 95+ models so I personally have never seen a newer hub assembly. The fact that bearings are available separately from the hub assemblies for 80's models told me they're serviceable, but I wasn't entirely sure how difficult that process was. But I do now!

In the back of my mind I was pretty sure it was a press fit component (what I was calling unit-hubs earlier), but I was hoping it was similar to the Warn kit where it is a loose assembly. Part of what helped fuel my hope was the bearing being available and the fact that a fair amount of XJers seem to refer late-model hub assemblies as unit-hubs, which makes it seem that earlier hubs aren't/weren't assembled in one package.

It does mildly change the complexion of the whole which way to go in terms of bearing assemblies. I'll stand pat with the late-model NAPA bearings. I can't honestly remember the mileage on them, but I know it isn't less than 9K and no more than 20K. As long as I don't have to change them more frequently than once a year, I won't complain. Does make me wonder why the change from tapered roller bearings to ball bearings. I like to think Jeep had a good reason to do it than to save themselves a few dollars.

Oh well, have a good holiday guys.

[Cruzin Illusion]

Originally Posted by LEAD_NOT_FOLLOW

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!

When I use to run a Dana 30 in the front I carried 2 stub shafts for that very reason. I have handed them down to my brother to carry now. This is something that you should educate others on if they wheel with a Dana 30. You can not believe how many people don't realize that the stub shaft holds the hub together. There was guy locally that did the same thing and it came apart while he was driving down the highway. He was very lucky that he just slide to a stop. I hear of a lot of people that break an axle and just pull the shaft out, stuff a rag in the axle tube and just head on down the road. This is why I would love to see a beginner get some hands on help with there rig so the experienced can show them how there rig works in general.

[shmoken875]

Originally Posted by tangofox007

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

I edited my original post to clear mis-information since this is one of the more tech-worthy threads thats been in here in a while. But thanks for the info, goes to show you can't always trust the parts guy (where I got my info).

[Bryson]

Originally Posted by Matt Gertsch

The point of the swap would be to get the roller bearings rather than ball bearings.

Indeed

Does make me wonder why the change from tapered roller bearings to ball bearings. I like to think Jeep had a good reason to do it than to save themselves a few dollars.

I'm almost certain that it was a cost issue. Ball bearings are almost always cheaper than roller bearings, and even easier to install. Even if it was a savings of just $5 per axle, that would equate to a huge cost savings.

They did do the right thing though and utilized two ball bearing units in each hub to take away some of the "twisting" thrust loads that wheel bearings typically see from turning, heavy braking...ect. However, there isn't a single ball bearing race out there that will be able to handle high thrust loads without producing a lot of deflection. Over time that deflection will substantially wear out the bearing (hence why so many people have to change them so frequently). This is where a tapered roller bearing really shines.

If anyone needs any more proof, this is what the Annular Bearing Engineers Committee (Abec) defines these types of bearings as:

Ball bearings: are best for higher speeds and light to moderate loads. Since the balls make little contact with the raceways, friction is lessened which makes higher speeds possible.

Roller bearings: generally support higher loads than ball bearings because the rollers make greater surface contact with raceways. There are four types of roller bearings:

3) Tapered— Cone-shaped rollers handle high radial loads, thrust loads, or both. They tolerate shock loads (suddenly applied loads), minor shaft misalignment, and are suitable for low to high speeds.

So does this count as "stickie" worthy?

[HeepToJeep]

Talk about perfect timing! You guys are currently discussing the same problem that's next on my repair list. After reading everyone's posts regarding the newer model Cherokees using ballbearings verses those prior to 1990 using cone rollerbearings I'm estatic that my truck's an 89 model!

By comparing prices/warranties of the five local auto parts stores and asking them to price-match their competition I'm going to be able to replace all four bearings and all six seals for about $70.00 and have a two year warranty on all of the parts....you can't beat that with a stick! I currently only have one noisey bearing but for the cost I'm replacing both sets verses go through this whole mess again at a later date.

In the past, when working on non-greasable hubs, housings and spindles I've drilled and tapped a hole to accept a greasefitting to permit ease of maintenance...once apart, I believe I'm going to do the same with these so that a routine greasing will prevent water and dirt buildup. My only concern is if the housing's thick enough to accept a fitting safely and that the seals are strong enough to prevent them from blowing out when grease is applied....I'd appreciate input if anyone has any.

Happy Holidays!
William