need help determining pinon angle.
need help determining pinon angle. Okay guys, I am getting a vibration at 70+ and it only appears when my foot is on the gas (in 6th gear). I am suspecting the tranny mount (I have an ES mount), but I want to make sure the mount didnt jack up my angle. Can someone tell me how to do this? I have read around, and I believe that the easiest place to look is on the tail shaft, and on the diff where the TA mounts. My dillemna is that I cannot get my car level. I am assuming it needs to be level, but I live in an apartment and only have two jack stands and a floor jack. Our lot is pretty hilly. How are you all determining if your car is level or not?
okay, after reading more, it seems that I can jack it up, and as long as the angle is the same for both, I should be okay regardless if the car is level or not. Can anyone confirm this? Also, I am assuming that the rear needs to be under a full load? I am going to use my floor jack to jack up the whole rear, Correct?
Last edited by J9_ls1; Oct 20, 2006 at 07:47 PM.
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Originally Posted by J9_ls1
okay, after reading more, it seems that I can jack it up, and as long as the angle is the same for both, I should be okay regardless if the car is level or not. Can anyone confirm this? Also, I am assuming that the rear needs to be under a full load? I am going to use my floor jack to jack up the whole rear, Correct?
You can never tell be looking at it.
First, I assume ES means a Energy polyurethane mount. It will throw off the angle, if you use the pre-load plate. If so, remove the plate and grind down the 2 bumps on the bottom of the poly mount. This will correct the angle and reduce most of the vibration. The stiffer mount will transmit more vibration regardless of angle. If you are not using the pre-load plate you should be OK.
With the car level and supension loaded, you can check the pinion angle with a protractor. The car does not have to be perfectly level. Find a flat piece of road somewhere. It is very difficult to get under the car with a protractor, when it is not on a ramp. Good luck and buy a protractor.
I believe the stock pinion angle is zero +/- 1/2 degree. So the pinion should point down about 1/2 degree more then the drive shaft angle.
I hope this helps.
JA
The way I do it is first measure the angle at the face of the crank pulley. The angle of the yoke should be the same (zero) or no more than one degree negative (downward).
FYI - The crank pulley face is normal (90 degrees) to the crank centerline which is parallel to the trans mainshaft centerline. Setting the pinion yoke at the same angle makes it normal to the trans mainshaft centerline. From there you adjust the pinion angle as desired.
FYI - The crank pulley face is normal (90 degrees) to the crank centerline which is parallel to the trans mainshaft centerline. Setting the pinion yoke at the same angle makes it normal to the trans mainshaft centerline. From there you adjust the pinion angle as desired.
THANKS GUYS, yeah I dumped the preload plate, and grinded down the bumps, but I am getting a vibration under load (foot on gas, 6th gear at 70mph). It is specific to speed I believe (70mph), so I am confused to what could be causing it. I am going to tighten down all my bolts for the rear tomorrow. We will see how that goes.
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Hi
If it is speed specific, as apposed to engine RPM, then it could be the angle. Check it carfully in all gears. When I installed the ES mount I got alot more vibration starting at about 2500 RPM. It vibrates at this RPM in all gears.
JA
If it is speed specific, as apposed to engine RPM, then it could be the angle. Check it carfully in all gears. When I installed the ES mount I got alot more vibration starting at about 2500 RPM. It vibrates at this RPM in all gears.
JA
