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General Site Info => Welcome => Topic started by: low79fx on November 24, 2007, 09:25:28 pm

Title: newbee
Post by: low79fx on November 24, 2007, 09:25:28 pm
 Was wondering does anyone know what the stock pinion angle is on an 86 GMC 1/2 ton SS ,I am going to install a 4 link.Want find out if the tranny shaft angle will need to be adjusted to match differential angle or do I just match differential to tranny angle as is ?What I am currently measuring as angle is 6 degrees which seems kind of extreme . Is anyone out there familiar with what I am trying to do? Please reply!!!Pics would also be extremely helpful,Thanks!!!
Title: Re: newbee
Post by: 79shortbed on November 25, 2007, 08:36:01 am
is you four link going to be adjustible(air bags,coil overs)?

how low will your truck be? if it will be about thesame as a truck 5/7 drop, find out the angle on the rear end of a truck with a drop.

what i would do is when ever you set up your ride hieght, eye ball and make it straight. Because with a good 4link your pinion wont change hardly under heavy throttle.
Title: Re: newbee
Post by: 79shortbed on November 25, 2007, 08:41:55 am
notice the pinion angle, its pretty straight and ride height is about 3in above that so pinion angle wont change that much.
i never had any problems with it.
(http://i32.photobucket.com/albums/d18/zachs92/mytrk5.jpg)
this is all the way up, pinion was a little off but had no vibration, but it never rode that high
(http://i32.photobucket.com/albums/d18/zachs92/whiteec3.jpg)
Title: Re: newbee
Post by: Captkaos on November 26, 2007, 11:46:34 am
GM trucks generally run a 4 degree pitch.  6 is kinda excessive, are your drivetrain mounts good?  The pinion should be the same as the transmission only pointing up.