Driveline angle problem.

[jpwindsor]

undefinedundefinedHello group, trying to figure out the best way to correct a driveline angle problem in my 65 Fastback. I am running a 95 302, AOD trans with a Windsor-Fox crossmember. The 9" rear axle is from a 59 Ranchero. The rear springs are 4.5 leaf double revese-eye with stock shackles. I measured 1.75 degrees at the rear axle and 4.5 degrees at the trans yoke. The engine mounts are the early-style. If I could raise the back of the trans, I could get a better yoke angle, however, the AODs larger case and extension housing prohibits that. Has anyone else run across this? I know prefered angles to be more than 1 but 3 or less. I have 3 degree pinion angle shims already installed to nose-up the pinion angle. Any feedback would be greatly appreciated. Thanks, Jay

 

[JB66]

How much can you lower the motor?

 

[jpwindsor]

I can probably lower motor 1/2 to 3/4 inch, there seems to be that much adjustment to the fan shroud. I can raise the trans only a little more than 1/8 inch.

 

[HyYoSilver]

Jay, as you probably already know, the driveline angles need to be nearly the same on both the transmission end and the pinion end. (if the pinion angle is 2* [positive], then the trans output should also be 2* [negative]) This holds true for a driveshaft with single u-joints on each end.

It sounds like you need to go down (rather than up), at the transmission output?????(Or am I looking at this wrong....? )Simply dropping the crossmember a bit would lessen the trans angle, and get the two angles more in line.

 

[WORTH]

Jay, as you probably already know, the driveline angles need to be nearly the same on both the transmission end and the pinion end. (if the pinion angle is 2* [positive], then the trans output should also be 2* [negative]) This holds true for a driveshaft with single u-joints on each end.

It sounds like you need to go down (rather than up), at the transmission output?????(Or am I looking at this wrong....? )Simply dropping the crossmember a bit would lessen the trans angle, and get the two angles more in line.

That's how I read it too, how is the rear hight? Can you lower the rear?

 

[JB66]

JP, are you measuring the angles relative to the 2 attached pieces or each piece relative to the horizontal plane (level, zero bubble)? The only way to lessen the angle (make it smaller) is to "straighten" the plane of the tranny to the horizontal plane. No? You said you can only raise the back of the tranny up about 1/8". If you can't raise the back, you have to lower the front.

 

[bk005]

What is more influential on d-shaft vibes(single cardan), U-joint angle, or keeping both yokes paralel. I worry more about keeping both yokes paralel, or actually keeping my pinion 1* down to comp for torque. If this is right Id just cut and rotate perches to desired.

 

[JB66]

Isn't the pinion supposed to be angled down? The axle torques the pinion up when you apply power, yes? Also, don't absolutely parallel (0*angles) create more vibration problems? Sorry for all the questions...I may need more learning...

 

[jpwindsor]

Jay, as you probably already know, the driveline angles need to be nearly the same on both the transmission end and the pinion end. (if the pinion angle is 2* [positive], then the trans output should also be 2* [negative]) This holds true for a driveshaft with single u-joints on each end.

It sounds like you need to go down (rather than up), at the transmission output?????(Or am I looking at this wrong....? )Simply dropping the crossmember a bit would lessen the trans angle, and get the two angles more in line.

Thanks to all for the replies! With the double reverse-eye springs in the rear, the driveline is going down-hill from back-to-front and it seems that lowering the crossmember would only worsen the angle. I may have to go to a mid-eye spring to restore proper angles, I hope not because the car sits really nice the way it is now.

 

[Route666]

You need to either raise the crossmember or lower the engine to rais the transmission output.

Where is your diff input pointed? If it's a standard diff that's been lowered and is now higher than the trans output, you'll most likely need to rotate the diff housing so that the angle is ok, and when you apply power it doesn't get even worse.

 

[pabear89]

Took awhile to picture your Problem.

But have you tried placing wedge shims on the backside of the Diff mounts?

What your discribing is reverse of the wedging for lifting 4x4s
to lessen the angle of the pinion.

PB