2001 XJ, AW4, 4.0 I6, 4WD, Stock height
18 months ago I put on Duratrac Tires (235/75/15 LT) and got a full alignment. These tires were slightly larger than the 225/75/15 I normally use and they cupped badly on the front. So I rebuilt most of the front end and replaced the following:
Ball Joints (Left side old balljoints had some play)
TRE's (Some play in old joints but not excessive)
Draglink
Pitman Arm
Steering Box (some play in the old box)
Axle shaft U joints (some play in old joints)
Wheel bearings
Rotors (old ones warped)
Front differential carrier bearings (one was badly worn, some heavy pitting on the race)
Front Shock absorbers Rancho RS 5000
After doing this work I replaced the tires with Firestone Destination A/T (235/75/15 LT) and got a full alignment. After 8000 miles rear tires look great but the front tires are starting to show cupping wear especially on the outer edges.
When I rebuilt the front end I didn't replace the lower or upper control arms or the coil springs. I am not sure if replacing these would help or not. Looking at my lower control arms it does look like the bushings have gone.
Regarding the coil springs Jeep doesn't service these anymore. According to my build sheet the front coil codes are:
Left front ZFKP
Right Front ZUJP
Crown automotive have a standard duty 16.5" coil Code ZVF and ZGF
and they have a heavy duty coil 17" Code ZGV, ZVJ and I'm not sure if these would be acceptable or not. I am fairly sure the coil springs I have on my vehicle now are original and not sure if they need replacing or not.
One last point regarding shock absorbers: I put on a slightly larger tire diameter 28.86" (235/75/15 LT Firestone Destination A/T) than normal and I wonder if I need a different length shock absorber for this modest increase in tire size? As I understand cupping is where the tire is hitting the road repeatedly and is often shock related and I also read that the control arms act a secondary shock.
Any advice / help would be greatly appreciated as this is really getting frustrating and expensive.
18 months ago I put on Duratrac Tires (235/75/15 LT) and got a full alignment. These tires were slightly larger than the 225/75/15 I normally use and they cupped badly on the front. So I rebuilt most of the front end and replaced the following:
Ball Joints (Left side old balljoints had some play)
TRE's (Some play in old joints but not excessive)
Draglink
Pitman Arm
Steering Box (some play in the old box)
Axle shaft U joints (some play in old joints)
Wheel bearings
Rotors (old ones warped)
Front differential carrier bearings (one was badly worn, some heavy pitting on the race)
Front Shock absorbers Rancho RS 5000
After doing this work I replaced the tires with Firestone Destination A/T (235/75/15 LT) and got a full alignment. After 8000 miles rear tires look great but the front tires are starting to show cupping wear especially on the outer edges.
When I rebuilt the front end I didn't replace the lower or upper control arms or the coil springs. I am not sure if replacing these would help or not. Looking at my lower control arms it does look like the bushings have gone.
Regarding the coil springs Jeep doesn't service these anymore. According to my build sheet the front coil codes are:
Left front ZFKP
Right Front ZUJP
Crown automotive have a standard duty 16.5" coil Code ZVF and ZGF
and they have a heavy duty coil 17" Code ZGV, ZVJ and I'm not sure if these would be acceptable or not. I am fairly sure the coil springs I have on my vehicle now are original and not sure if they need replacing or not.
One last point regarding shock absorbers: I put on a slightly larger tire diameter 28.86" (235/75/15 LT Firestone Destination A/T) than normal and I wonder if I need a different length shock absorber for this modest increase in tire size? As I understand cupping is where the tire is hitting the road repeatedly and is often shock related and I also read that the control arms act a secondary shock.
Any advice / help would be greatly appreciated as this is really getting frustrating and expensive.