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Does anyone know the pinion angle for a front HP30 with 4" of lift and a tummy tuck?


astjp2

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So does anyone know what the pinion angle is for a front HP30 with 4" of lift and a tummy tuck? I am going to cut my inner C's off and I have to install new mounts so I am looking to get it close for the caster and pinion angle. Front shaft is a CV...

Thanks,
Tim
 
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astjp2

astjp2

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Thanks, Jerry, but what I am looking for is what other people are set at, so when I cut and weld the inner C's back on, I can set my pinion angle and my caster close to what I want it.
 

hosejockey61

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I think you are asking your question wrong....with no other factors, the pinion angle should be 0 to best eliminate vibrations, meaning the driveshaft is in line with the pinion yoke (or 90 degrees if you are measuring off the face of diff cover mating surface.

Stock caster is set at 7 degrees. So if you are re-welding inner C's on and you are looking to go with stock caster specs, then shoot for 7 degrees with the pinion angle set at 0. Does that make sense?

My .02
 

Steel City 06

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I think you are asking your question wrong....with no other factors, the pinion angle should be 0 to best eliminate vibrations, meaning the driveshaft is in line with the pinion yoke (or 90 degrees if you are measuring off the face of diff cover mating surface.
I think he’s asking for what absolute angle people have on their axle as correctly installed. I.e., if you were to put an angle finder on your front driveshaft with the rig level, what number would you find?

I have a TJ D44 which is low pinion so I cannot provide a useful answer.
 
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hosejockey61

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I think he’s asking for what absolute angle people have on their axle as correctly installed. I.e., if you were to put an angle finder on your front driveshaft with the rig level, what number would you find?

I have a TJ D44 which is low pinion so I cannot provide a useful answer.
It will be different (albeit slightly) for everyone depending on weight. Not all 4" lifts are 4".... Some high, some low. Add in heavy bumpers and winches and you have even more differences.

Get your pinion angle where you want it and mark your tubes/C's with caster at 7 degrees.
 
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astjp2

astjp2

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It will be different (albeit slightly) for everyone depending on weight. Not all 4" lifts are 4".... Some high, some low. Add in heavy bumpers and winches and you have even more differences.

Get your pinion angle where you want it and mark your tubes/C's with caster at 7 degrees.
I just want to get it close so if I am welding it back together it wont require any reduction of caster and still have a good driveshaft alignment.
 

Wildman

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I just want to get it close so if I am welding it back together it wont require any reduction of caster and still have a good driveshaft alignment.
Maybe this will help some. I would guess the measurements to be close to the same. I went with a total of 11* of caster & pinion angle based on my 4-6" lift I had planned. 7* caster and 4* of pinion angle.

 
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astjp2

astjp2

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Maybe this will help some. I would guess the measurements to be close to the same. I went with a total of 11* of caster & pinion angle based on my 4-6" lift I had planned. 7* caster and 4* of pinion angle.

Those were the numbers I was going to use. Thanks Tim
 
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