Pinion Angle ?

I got my SYE in and am setting up my pinion angle. From the measurement I just took, the driveshaft is at 13 degrees and the pinion is at 16 degrees.

I wonder why it vibes?:confused1

Its at 16 degrees because of the 6 degree shim I have back there, which is obviously coming out. Which will give me driveshaft 13 pinion 10. I have read anywhere from 1 to 2.5 degrees lower is desired to account for axle wrap. Will 3 degrees be ok or do I need a .5-1 degree shim in there?

a 2 would probably be best. dont forget tho that the driveshaft will have slight changes in angle from the pinion moving. id take the shim out and remeasure and go from there.

The angle of the driveshaft will change slightly when you lower the pinion too. I would remove the shims and see where it goes from there.

2* shim

I think you're probably going to have to put something back in there. Remember, driveshaft and pinion angles are are not independent of one another. As you move your pinion angle down, your driveline angle will steepen. This means that while removing your shims may result in a pinion angle of 10*, your driveshaft angle won't remain at 13* unless you were to disconnect it at the pinion yoke. Draw out a before and after picture of your angles on a piece of paper and you will see what I mean.

I can't tell you exactly what angle it will end up at (that is a function of drivshaft length and involves more math than I care to remember at this point in my life) but I can tell you it won't remain at 13*. I would guess somewhere around 15*, but that is purely a WAG.

OK, totally got beat to the punch on that one... I started my response, ran a call for a fire alarm at the college, and then returned to finish my response. Glad to see some others jumped in while I was gone.

ya its pretty much a lower pinion angle equals a steeper shaft angle. so as others said id take the shims out find my angles and calculate whats needed from there

Take the shims out and see what I have. Makes sense to me, thanks for the responses. :cheers:

Ideal is still 1-2 degrees lower right?

Yes, 1 or 2 degrees lower will allow for axle wrap.

Ive found you get about x1.3 net change which means your 6* shim would be about 7.8* of change!