4 Link guru's i need pinion help...

Ok im putting a ford 8.8 disc brake rear in my truck and redoing the 4 link When i did the 4 linked it the first time it still had the stock motor and trans now it has a 351w and a c6, With an angle finder on the tailshaft of the tranny and the truck level and at ride height it is deal on 0 degrees, Now for the pinion it's suposed to be opposite right like if the tranny was -2 the rear would be +2?? But since the tailshaft of my tranny is at 0 degrees what should i set the pinion too 0??? Also i am running a built 1pc driveshaft. And a suicidedoors triangulated 4 link with bag over axle...

Ok i think i got it figured out but correct me if im wrong since my tail shaft is at 0 degrees, as long at i set the pinion up at + or -, 2 to 3 degrees at drive height all be good.

yes you want to cancel the vibrations. so if your tranny is at 0, then the axle being at 0 degrees is where you have equilibrium.

BUT this is the deal. leaf springs, and bushings on link setups flex. so you should actually set the pinion a little below the equilibrium point ( in your case 0 degrees). how much is really depending on the power of the motor. this is so because when you stomp on the gas, the torque from the driveshaft will actually want to pull the axle upwards. try spinning your axle's driveshaft flange forward, it will want to point up!

this is really where i can't help you since i dont have experience with built motors. but MY personal rule of thumb is with poly bushings, set it between 1-3degrees below equilibrium. just play with it until you feel no more vibration.

if i was you, i'd set it between 2-3 below.


and here's a tip. you do not necessarily have to have the vehicle LEVEL when you are setting up your pinion. this is because the drivetrain does not really care if the vehicle is uphill or downhill. it cares what the alignment is within itself. so with that said. just jack the truck up. keep it at that location. if your tranny is at 34degrees at that position, so what? then set the axle at -34. get the gist? this is why i was saying equilibrium. because your tranny angle is at 0 at that height you measured it at. 0 isnt always going to be the correct angle


ok pm about yer driveshaft

yes either way will work. + or -. since either way as long as the working angles cancel each other out, then you are set.

but just for the "looks" part. set it downwards. mainly because you'll get less hassle from ppl that judge too quickly. and you won't have to cut out as much of the crossmember if you point it downwards

Ok thanks alot man, i didn't even really think about it wanting to push the pinion up when u hope on it i'll set it at -2 when i redo the 4 link then mess with it from there!

you could space the rear of the tranny up to like a +2 or +3 degrees then have the rearend be -2 or -3.

could u post some bed pics for us? thanks -bf

Some bed pics?? u mean like this

Robbie if u'd space the rear of the tranny up +2,3 degrees i'd sent the pinion at like 0,1 degrees.

damn your truck is sweet