Front Pinion angle vs Castor- offroad rig only
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Year: 1995
Model: Cherokee
Engine: 4.0
Front Pinion angle vs Castor- offroad rig only
I know this is a subject beaten to death, but most threads are relative to a daily driver.
So for my rig:
6" lift
35's
4.88 gearing
Dana 30HP
Short arms- uppers are adjustable
This is a trailered Jeep that only sees the road between trails. How important is Castor angle vs Pinion angle, and if Castor isn't an issue then what would be ideal pinion angle?
Ive read a number of threads and honestly varying opinions makes it difficult to decipher. In fact, this thread may just make it more confusing......
So for my rig:
6" lift
35's
4.88 gearing
Dana 30HP
Short arms- uppers are adjustable
This is a trailered Jeep that only sees the road between trails. How important is Castor angle vs Pinion angle, and if Castor isn't an issue then what would be ideal pinion angle?
Ive read a number of threads and honestly varying opinions makes it difficult to decipher. In fact, this thread may just make it more confusing......
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Year: 93 2 door
Model: Cherokee
Engine: 4.0
as your pinion points up, your caster goes negative. this is bad for drivability and is the reason why people cut and turn their C's to maintain good pinion angle and caster
as your pinion points to the ground, your caster goes positive. this is good for drivability but your pinion will be too flat at your lift height and your driveshaft will bind, this is why I recommend running a lower lift height. welcome to the conundrum!
for an offroad only rig going at crawl speeds I would be shooting for -1 to +3 degrees caster and see where your pinion angle is at. If you can't obtain that goal, time to cut the coil springs or get long arms
as your pinion points to the ground, your caster goes positive. this is good for drivability but your pinion will be too flat at your lift height and your driveshaft will bind, this is why I recommend running a lower lift height. welcome to the conundrum!
for an offroad only rig going at crawl speeds I would be shooting for -1 to +3 degrees caster and see where your pinion angle is at. If you can't obtain that goal, time to cut the coil springs or get long arms
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Year: 1995
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As the XJ goes up, the coils seem to twist as well ie: top isn't aligned with bottom or even close. Cut & twist the C is coils? how much to cut and does twisting them straighten them out?
I liked the height I had but the plan is 35's so I'm looking for the extra clearance. Frame will be stiffened as well- new gears to 4.88 sitting on the shelf.
I can wrench but Jeeps is new- learning as I go and enjoying every second....
Thank you Atmos for the input
I liked the height I had but the plan is 35's so I'm looking for the extra clearance. Frame will be stiffened as well- new gears to 4.88 sitting on the shelf.
I can wrench but Jeeps is new- learning as I go and enjoying every second....
Thank you Atmos for the input
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Year: 93 2 door
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I would guess that your control arms are not designed for a lift this tall. Can you post a picture from the side of how your coils are sitting?
Ignore what I said about cut/rotate C's. That's advanced fabrication. It's involves cutting off your knuckles and and rotating them to fix your caster
Ignore what I said about cut/rotate C's. That's advanced fabrication. It's involves cutting off your knuckles and and rotating them to fix your caster
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Year: 1994
Model: Cherokee
Engine: 4.0
for off road only caster is not important set your pinion so you do not eat up joints and bearings the only thing about - caster is your steering will not return to center by its self after turning
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That's what I was thinking and went ahead and set it up with a good pinion angle and didn't worry so much about castor. Hell once I got it all together it ended up looking pretty good.
I had the coils in but didn't spin them into position on a mock up so they were bulging. Once I got everything lined up and wrenched down it came out nice
The coil spring retainer clip bolts- I've seen numerous posts about how they won't tighten. Self tapping bolts usually aren't good for multiple uses- I just got some 3/8" self tap bolts, drilled the clip holes a little larger and bingo- good to go
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Year: 93 2 door
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Looks like you can spare a couple degrees at the pinion amd still keep the ujoints at operating angle. But that's just by eye
I thought you meant the coils were cocked front-back not side-side. The picture of your coil springs indicates that your axle may not be centered. Once again that's by eye.
I thought you meant the coils were cocked front-back not side-side. The picture of your coil springs indicates that your axle may not be centered. Once again that's by eye.
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Year: 1995
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Looks like you can spare a couple degrees at the pinion amd still keep the ujoints at operating angle. But that's just by eye
I thought you meant the coils were cocked front-back not side-side. The picture of your coil springs indicates that your axle may not be centered. Once again that's by eye.
I thought you meant the coils were cocked front-back not side-side. The picture of your coil springs indicates that your axle may not be centered. Once again that's by eye.
Ya you're right- trac bar is still disconnected and I moved to the back to install the leafs- from what I've done in the past is to compress the suspension a few times with trac bar disconnected to center the axle. Is this correct or what do you suggest?
Last edited by AceWhite; 08-25-2016 at 11:14 PM.
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Year: 93 2 door
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yours is offroad only so you could probably do it by eye like that yeah. the hack I use is tying string to the frame rail and let them hang down to the axle with weights on them. Then play with the measuring tape until they're close.
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