Fox T-Bird/Cougar Forums

Technical => Drivetrain Tech => Topic started by: QUICKSHIFT on September 18, 2018, 06:36:41 PM

Title: What pinion angle to use on 84 cougar?
Post by: QUICKSHIFT on September 18, 2018, 06:36:41 PM
I'm chasing a drive line vibration which I suspect could be caused by the pinion angle being off. I have the lower arms with the eccentric adjustable oval bushings. When I rebuilt the entire rear end suspension and added lowering springs, I may have not set the angle correctly.  Any one have pinion angle specs for an 84 Cougar?
Title: What pinion angle to use on 84 cougar?
Post by: EricCoolCats on September 18, 2018, 08:12:45 PM
Should be between 0 and 4 degrees IIRC.

Check the driveshaft for weights...that could be causing rotational vibration.
Title: What pinion angle to use on 84 cougar?
Post by: QUICKSHIFT on September 18, 2018, 08:16:37 PM
Quote from: EricCoolCats;467150
Should be between 0 and 4 degrees IIRC.

Check the driveshaft for weights...that could be causing rotational vibration.

Thanks Eric.
Title: What pinion angle to use on 84 cougar?
Post by: thunderjet302 on September 18, 2018, 09:37:52 PM
What speed or RPM is the vibration happening at? When I went to 3.73 gears I never got the stock driveshaft to balance. I ended up having to replace the stock driveshaft with a 3.5" diameter aluminum driveshaft.
Title: What pinion angle to use on 84 cougar?
Post by: QUICKSHIFT on September 19, 2018, 11:05:33 AM
It's more harmonic than vibration. I thought it was the front tires, but after upgrading to sport comps, its still there.
Title: What pinion angle to use on 84 cougar?
Post by: thunderjet302 on September 19, 2018, 07:56:56 PM
Did the vibration start with the 4.10s? Does it only happen at a certain speed? Can you go faster and the vibration/harmonic goes away?