Front pinion angle.
#1
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Year: 1999
Model: Cherokee
Engine: 4.0L
Front pinion angle.
I was just noticing that my front pinion isn't pointed up at all with my new LA kit. I think it is creating some driveline vibes. I never had any before and I'm seeming to get some. What way should I go about handling this. I Had it aligned and they didn't say anything about adjusting my UCA lengths so I have them at what RE recommended.
#2
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Year: 1990XJ/1989MJ
Model: Comanche
Engine: 4.0L Renix
Are the RE UCAs adjustable? If so then lengthen them until they point your pinion towards the transfer case. I have never heard of front driveshaft vibrations with a RE kit under 6" but each Cherokee is different.
#3
Take it back in and have the measure the caster. It should be 6-8 degrees. Adjusting the caster to those numbers will insure proper Return to Center and correct your pinion angle at the same time.
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Year: 2001
Model: Cherokee
Engine: 4.0
Most alignment shops won't touch caster, even if you have adjustables. Ask me how i know. Go back and see if they will do it, if not get an angle finder and measure/adjust.
#5
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Year: 1999
Model: Cherokee
Engine: 4.0L
Here is a couple of pics showing the angles of the DS and pinion. They arent that extreme but it seems to be giving me problems.
#7
The most accurate way is to put your anglefinder in the machined flat portion of the inner C, but since you probably don't want to diassemble your axle to do that...
http://go.jeep-xj.info/HowtoAlignment.htm
http://go.jeep-xj.info/HowtoAlignment.htm
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#9
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Year: 1999
Model: Cherokee
Engine: 4.0L
Those are the specific lengths that RE gave in the instructions for my lift. I only did what they said. If I lengthen the UCA's how far should I go? I read the go jeep info but i'm kinda clueless without step by step pics.
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Year: 2001
Model: Cherokee
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If you don't feel right doing this, have a shop do it for you.
Last edited by muddeprived; 09-08-2008 at 01:35 AM.
#11
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Year: 1999
Model: Cherokee
Engine: 4.0L
If you can't figure it out, do it the redneck way. Lengthen the upper arms 1/4". Test drive it. If steering still feels alright and vibes are lessened or eliminated, call it a day. If you need more, lengthen them 1/8" (a.k.a. two turns) more and keep doing 1/8" it till it's right. Focus on the steering mostly because you'll start to notice it changing a little bit everytime you adjust the caster. You won't crash and burn if your caster is a little off so don't be nervous. You will notice change in the return-to-center with the steering as you adjust and maybe get touchy or not. This is all based on my experience on the TJ. I knew how the steering handled and what i wanted so i adjusted the caster this way and had a shop print a read-out on the angles and i was in the ballpark of what was acceptable caster. I got lucky or i just knew the jeep very well.
If you don't feel right doing this, have a shop do it for you.
If you don't feel right doing this, have a shop do it for you.
#12
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Year: 1999
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Okay I ended up taking the UCA's from 15 3/4" to 16 1/4". That 1/2" got rid of the driveline vibes. I'm still gettting some vibes when I hit the brakes though. Also in the mornings when I back out I hear a weird knid of rubbing noise. This is leading me to believe that my Wheel bearings are going out. What is an okay brand to buy? Good quality with a fair price?