Adjusting pinion angle process!
08-27-2014, 09:44 PM
#1
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Adjusting pinion angle process! Damn is pinion angle a mother to set. I was at a positive 4 degrees so I am trying to make adjustments. I have unbolted the sway bar,lower control arms the t/a from the top diff and bottom diff. I have also loosened the front t/a joint but still have the bolt in it. What is the order of adjusting it and am I going about this the proper way? At this point I have the pinion angle set at -2 but everything is still loose. Please explain to me which I bolt and adjust first as there are many adjustments to be had at all the joints. I need help like yesterday It's on the alignment rack at work.
Mwc 9
Mwc long t/a
Double adjustable lca
Double adjustable phb
Double adjustable sway bar end links
2000 camaro auto
Mwc 9
Mwc long t/a
Double adjustable lca
Double adjustable phb
Double adjustable sway bar end links
2000 camaro auto
08-28-2014, 04:10 PM
#3
it sounds like you're doing it all wrong 
have everything installed suspension-wise and tight, as if you were ready to drive it on the road. you definitely can't have the torque arm bushing/mount loose!
you do not need the drive shaft installed, and it may be easier to measure with it removed. I also find it easier to have the exhaust Y pipe removed. I use a harbor freight magnetic digital inclinometer.
http://www.harborfreight.com/digital...uge-95998.html
with the drive shaft installed i measure on a flat of the slip yoke at the transmission, and on the flat of the rear axle pinion yoke. if you don't use the drive shaft then you don't have a slip yoke to measure off of up front, so measure the vertical face of the transmission output shaft then add/subtract 90° to do the math of what the phase angle is.
the only thing you should be adjusting is the adjustment nut on the torque arm.
and when measuring off the flat of the yokes, you have to rotate the yokes so the flat you measure off of is parallel to ground. i hold something like a pencil by the tip and let gravity give an up/down vector, and rotate the yoke so the side of the inclinometer is parallel with the hanging pencil... this way you know you're making a 2 dimensional angle measurement with respect to gravity.
have everything installed suspension-wise and tight, as if you were ready to drive it on the road. you definitely can't have the torque arm bushing/mount loose!
you do not need the drive shaft installed, and it may be easier to measure with it removed. I also find it easier to have the exhaust Y pipe removed. I use a harbor freight magnetic digital inclinometer.
http://www.harborfreight.com/digital...uge-95998.html
with the drive shaft installed i measure on a flat of the slip yoke at the transmission, and on the flat of the rear axle pinion yoke. if you don't use the drive shaft then you don't have a slip yoke to measure off of up front, so measure the vertical face of the transmission output shaft then add/subtract 90° to do the math of what the phase angle is.
the only thing you should be adjusting is the adjustment nut on the torque arm.
and when measuring off the flat of the yokes, you have to rotate the yokes so the flat you measure off of is parallel to ground. i hold something like a pencil by the tip and let gravity give an up/down vector, and rotate the yoke so the side of the inclinometer is parallel with the hanging pencil... this way you know you're making a 2 dimensional angle measurement with respect to gravity.
Last edited by 1 FMF; 08-28-2014 at 04:16 PM.
08-28-2014, 04:32 PM
#4
Yeah man, take a step back and cool off. You shouldn't have to loosen anything to adjust pinion angle. Just turn the adjuster on the bottom of the torque arm. It should be super easy to do. Make sure you are measuring the driveline angle from an accurate spot, such as the crank pulley or front u-joint cap. Then measure the pinion at the torque arm mount or rear u-joint cap. Your "pinion angle" will be the difference in these 2 measurements. Your pinion should always be at less of an angle than the driveline to allow for preload. This is where the -2* always comes in to mention. Try this method and see if that doesn't make your life much easier 
08-29-2014, 10:50 PM
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A big part to what i think was/is the problem is that It was at +4 degrees on the diff 0 on the shaft and my front ta joint is on the highest hole. When I moved the lower nut on the diff to adjust it did not move much and required excessive force to keep turning. I knew that turning that lower nut it would adjust some. But it didn't so I just stopped and started unbolting things until it moved easier. Now I think my lower adjuster is too far adjusted.
So basically I need to redo it, this time gonna (1) lower the front ta joint lower (2) run the others on the diff closer in(3) and adjust accordingly.
How many threads on the front one for a starting point?
So basically I need to redo it, this time gonna (1) lower the front ta joint lower (2) run the others on the diff closer in(3) and adjust accordingly.
How many threads on the front one for a starting point?
08-30-2014, 10:15 AM
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Measuring the driveshaft tells you u-joint working angles not pinion angle. Geez I wish people would stop throwing terms around or describing crap they don't know anything about, this is why its so hard to get a straight answer about how to set a pinion angle and people get so twisted up and confused.
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08-31-2014, 06:05 PM
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Tell you what worked for me.
Put some weight in the seats, lift the car, measure the angle of the input shaft to the rear axle. Measure the angle of the transmission output shaft - use the crank pulley for this. Make them match. My transmission and axle are both 3.5 degrees uphill from rear to front. No vibrations.
Put some weight in the seats, lift the car, measure the angle of the input shaft to the rear axle. Measure the angle of the transmission output shaft - use the crank pulley for this. Make them match. My transmission and axle are both 3.5 degrees uphill from rear to front. No vibrations.
