quick unit bearing question

[JEEPERZ]

the old one on the left doesnt have a gap. is this normal with new unit bearings or did i get the wrong ones?

[JeepcoMJ]

the old one on the left doesnt have a gap. is this normal with new unit bearings or did i get the wrong ones?

 

you probably got the newer ones, which still fit but are thinner.

 

can't run them without newer shafts unfortunately.

 

maybe also do your ujoints before you install the unit bearing.. :roll:

[JEEPERZ]

the old one on the left doesnt have a gap. is this normal with new unit bearings or did i get the wrong ones?

 

you probably got the newer ones, which still fit but are thinner.

 

can't run them without newer shafts unfortunately.

 

maybe also do your ujoints before you install the unit bearing.. :roll:

 

bummer, can i still get the older ones though?? ill just take these back and get the right ones ordered if thats the case.

[Eagle]

It isn't just the shafts that are different. The newer hubs have a different spacing from the face of the disk mounting surface to the surface where the hub mounts to the knuckle. This is due to changes in the rotors and calipers between 90 and 91. You can't run the newer hubs on the older knuckles and vice versa.

 

In general, the parts to be concerned with in keeping the front brakes compatible are the steering knuckles, the hub/bearing assemblies, the rotors, and the calipers. (There is a more complete enumeration of the interrelationship of these parts in Chapter 6, Axles.)

 

· Only two steering knuckle designs were used: 1984 through 1989, and 1990 through 2001. Left and right side knuckles are different part numbers within each group.

 

· Three different hub/bearing units were used. The hub/bearing units are the same for both sides of the vehicle. The different years for hub/bearing assemblies were: 1984 through 1989; 1990 through mid-1999 (composite rotors); and late-1999 through 2001 (cast rotors).

 

· Three rotor types were used: 1984 through 1989; 1990 through mid-1999 (composite); and late-1999 through 2001 (cast).

 

· Only two caliper types were used: 1984 through 1989, and 1990 through 2001. Left and right side calipers are different part numbers within each group.

 

The front hub/bearing units are usually serviced by replacement. The early (1984-1989) hubs use tapered bearings, while the newer hubs use ball bearings. Replacement bearings and oil seals are available for the early, tapered-bearing hubs. However, service requires a heavy-duty shop (arbor) press to remove the old bearings and install the new ones. Unless you have access to a shop press with bearing removal fittings, attempting to rebuild a hub assembly is probably not cost-effective unless you have access to the equipment needed to perform the work yourself. Using prices from the Fall 2004 Quadratec catalog, for example, a complete hub/bearing assembly lists for $129.95. This price is competitive with prices from other aftermarket sources. Quadratec sells the inner and outer bearings plus inner, center and outer oil seals to service the early-style hubs as individual parts, with a total price of $59.75. They also sell the complete parts set necessary to rebuild one hub as a kit, for $49.95. Clearly, rebuilding a hub can be economical if you can perform the work yourself. If necessary to pay for shop time and labor, the cost could quickly equal or exceed the cost of a new hub/bearing assembly.

 

The above is copyrighted by me and by posting it here I am NOT granting anyone permission to re-post it anywhere else. Each member here may print ONE copy to stick in your technical notebook. That's it. It's part of a book I've been working on, and I would appreciate your being honest and ethical enough to not give away my intellectual property.

[JEEPERZ]

well i must need to buy the 89 unit bearings then. doesnt make sense to me cause my truck is a 90. maybe its just that brand that is off. they were jks and were $175.00 each. thanks for all the input.

[Eagle]

well i must need to buy the 89 unit bearings then. doesnt make sense to me cause my truck is a 90. maybe its just that brand that is off. they were jks and were $175.00 each. thanks for all the input.

Are your front rotors cast, or composite?

 

If you don't know the difference, look at the outer edges/corner of the "hat" section that fits over the hub. If the outer corner is square(ish) and sharp, you have cast rotors -- which are the old style. If the corner is sort of rounded off, it's sheet metal "hat" indicating composite rotors, which would need the 90+ hubs.

[JEEPERZ]

the old one on the left doesnt have a gap. is this normal with new unit bearings or did i get the wrong ones?

 

you probably got the newer ones, which still fit but are thinner.

 

can't run them without newer shafts unfortunately.

 

maybe also do your ujoints before you install the unit bearing.. :roll:

 

Wouldnt it be fun to put in the joints with the bearings in. Come on :roll:

 

I have cast, so I'll order the older ones.

[jtdesigns]

The above is copyrighted by me and by posting it here I am NOT granting anyone permission to re-post it anywhere else. Each member here may print ONE copy to stick in your technical notebook. That's it. It's part of a book I've been working on, and I would appreciate your being honest and ethical enough to not give away my intellectual property.

 

Reuse it?? Hell with that just hurry up on that book so I can buy one!!!!! For real...

[carnuck]

Looks like the difference between the OEM and made in China hubs (I see them a lot at work)