Disco on a 91?

[Geonovast]

So I'm at my dad's helping him dig out my stroker 4.0 donor, and I notice he had different size tires on the front and back(he threw some he had laying around on the front to get rid of the DW temporarily) And I mention to him to absolutely under no conditions is he to put it in 4wd. He says ok, then he mentions he's been having a clunk by the left front tire, so I crawl under to take a look.

 

Bearing feels ok, ball joints are fine, wheel u joint is fine, tie rods are fine, then I wiggle the front DS to check the joints...and it turns. I look over and see the disco housing.

 

He had replaced one bearing at one point and of course ordered the part for a 91. He now tells me that they looked different when he changed it but he put it on anyway.

 

Soooo basically, was the disco axle ever used on a 91? It was suggested to me that it was a late production 90 tagged as a 91 but it's an HO...

 

Also, is having those two seperate style bearings going to be a problem?

 

91 XJ 4.0 HO/Ax-15/231

[Eagle]

Also, is having those two seperate style bearings going to be a problem?

Yes.

 

I've posted the run-down on hub/knuckle/rotor/caliper combinations a couple of times. They do not mix-n-match.

[Geonovast]

Thought so, but he doesn't listen to me unless it's backed up by professionals, aka you fellas.

[Eagle]

Print this out for him:

 

Steering knuckles: There are two designs of steering knuckle, and within each design the left and right sides are mirror image and carry different part numbers. The early knuckles were used from 1984 through 1989. The late knuckles were used from 1990 through 2001.

 

Hub/Bearing: Three different hub/bearing assemblies were used. The hub/bearing assembly is the same for both sides of the vehicle. The first type was used from 1984 through 1989, and must be mated to the early steering knuckle from the same range of years. The early hub/rotors used tapered roller bearings, which are available as individual replacement parts, and in theory can be rebuilt. In practice, removing the old bearings and installing new ones requires a large arbor press and bearing splitter, equipment not available to the average owner. In practice, even dealerships simply replace the entire assembly, because the labor cost to rebuild would exceed the cost of a replacement assembly.

 

The second type of hub/bearing assembly was used from 1990 through mid-1999. This hub/bearing assembly mates up with the newer style steering knuckle and is used with composite rotors. Certain years of XJ with composite rotors were subject to a safety recall if they were located in northern “rust belt” states, because of problems with the rotors (see below). When replacing hub/bearings in vehicles within this range of years, unless the vehicle recall history is known it is wise to call a dealer or DaimlerChrysler customer service to determine whether or not the vehicle has undergone the brake rotor recall. If so, confirm which hub/bearing assemblies should be used as service replacements..

 

The third type of hub/bearing assembly was used from mid-1999 through 2001. This hub/bearing is also used with the new style steering knuckles, and is mated with the newer style cast rotors.

 

Rotors: Three types of rotors were used. Rotors are the same for left and right sides. The first style of rotor was used from 1984 through 1989. The second style of rotor was used from 1990 through mid-1999. This second style rotor was a “composite” design—the braking surface disc was separate from the center “hat” section, which was stamped from comparatively thin sheet steel. After several years of service, it was found that in states and localities where salt is used on the roads in winter, corrosion of the “hat” section could result in the disc portion separating from the assembly, causing a loss of brakes. A factory recall was issued to correct this problem. The recall affects only vehicles within a range of years, and only in certain states. Anyone owning a Cherokee or Comanche in the range from 1990 through 1999 is advised to call a dealer or DaimlerChrysler customer service with the VIN number to determine if the vehicle is subject to this recall.

 

Mid-year in the 1999 model year the front brakes were changed to an all cast rotor design. Although the original, early style rotors were also all cast, the new rotors are different from the early ones and carry a different part number. The new cast rotors were used from mid-1999 through 2001. Because 1999 was a transition year, owners of 1999 Cherokees will need the VIN number to determine the correct parts to order when servicing the front brakes or hub/bearing assemblies.

 

Calipers: Two styles of caliper were used. The calipers are mirror image for the left and right sides and carry different part numbers within each group of years. The early style caliper was used from 1984 through 1989. The later style caliper was used from 1990 through 2001 and is used with both the composite rotors and the newer cast rotors.

 

As previously noted, a complete front axle assembly from any year Cherokee or Comanche can be installed in a Cherokee or Comanche of any other year. It is only when attempting to swap components among different years that the above parts differences become critical.

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