VGMStudios

I'm a bit confused and frustrated.
I've been reading a lot how to set the pinion angle and no one can give me a definite answer. All this misinformation and non direct answers is really frustrating!

I lowered my car with poly bushings.
I read that you should set the pinion angle to 1° or 1.5° nose down.
Does this mean that I need to set the pinion angle AT 1.5° OR subtract it from whatever the transmission flang is set at????
So for example.
If my transmission flange is at 4° do I subtract 1.5° to get 2.5° and set the pinion angle to 2.5° OR just set the pinion angle to 1.5° nose down?

Can anyone please give me a definite answer to this?

Bert

Sorry but I have another non-direct answer because I have had a hard time getting a real clear answer on this also. The basic idea is that you want the angles on each end of the driveshaft to be equal and opposite, when the driveshaft/differential is under load. Part of the mystery has to do with how much the rear axle rotates under load; because you are setting the angle with no load on it.

Do you have the stock two-piece driveshaft, or an aftermarket "one-piece" without the center joint? If stock two-piece, then the angle is less critical.

For a one-piece driveshaft, I was told by Shaftmasters that -1 to -1.5 degrees on the pinion end (nose down like you say) is "correct" and I believe this is based on an assumption of the transmission angle and the amount that the rear axle rotates under load.

Also "pretty sure" that vibration is the final test -- if it runs smooth with no noticeable vibration or pulsing coming from the driveshaft, then it's "good"

VGMStudios

Thanks for replying Bert. It's ridiculous that we can't get a definite answer from anyone.
I have a one piece driveshaft. Its stock (V6).
I understand that both places need to be parallel when under load but no one can tell me if it's ACTUALLY 1.5 or 1.5 minus whatever the angle is on the transmission.
I've set my pinion angle twice. Once at 1° and back to stock t 0.55° and I get vibrations and a funny noise coming from the rear while going over 140km/h. So I want to be extra sure to set it a third time cause I don't want to break anything back there.

VGMStudios

Finally. A direct answer about the pinion angle. This guy says 2° difference but others say 1.5°. Would 0.5 really make that much of a difference?

Bert

I didn't realize the two-piece driveshaft was GT only. That might explain some of the driveshaft failure stories we have heard about the V6. (2011-2012 model years if I remember correctly)

if the Transmission output shaft is pointing "up" two degrees, you want the differential input shaft pointing "down" two degrees, when it is under load. The trick is estimating how much the rear axle will rotate under load; I am not sure which direction or how much it rotates (due to the play/give in the upper control arm bushings and the lower control arm bushings to a lesser extent)

And if I want to confuse myself even more, I think about what happens when you lower the car . . . the transmission moves down, the rear axle/differential does not move, so now the transmission is lower in relation to the axle/differential.. . . .but . . . the angles do not change????

EDIT: I was posting at the same time as you . . . haven't watched the video yet, don't have time at work (already wasting too much time!) . . . yes I think half a degree could be important, worth a try