Author Topic: driveline vibration help  (Read 3597 times)

Offline MyMopar

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Re: driveline vibration help
« Reply #15 on: September 15, 2008 - 12:44:21 PM »
So I would need to be either at 10* nose down at the diff to make the 5* difference?

So if I am 4* nose down at the pinion right now , I can technically raise the tailshaft to 1* positive and I would have the 5* difference we are after?  Am I correct in thinking this or is there another factor I am overlooking.
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!




Offline Moparal

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Re: driveline vibration help
« Reply #16 on: September 15, 2008 - 04:39:58 PM »
Doesnt really take but 45 minutes or so start to finish. Maybe take a 2 degree wedge and try it going up. One way is when crusin and acc the other is down. I had to do mine twice and went 2 up and all is normal now. I went 2 down and the vibe was bad.

Offline ShelbyDogg

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Re: driveline vibration help
« Reply #17 on: September 15, 2008 - 05:06:38 PM »
I would try a different driveshaft and a friend's wheels and tires.
Rob

3 E-bodies, Megasquirt-1v3.0, Edelbrock Pro-Flo-1, Holley C950, FAST EZ-EFI; say no to carbs...yes to throttle bodies

My Pace Car restoration thread:
http://www.cuda-challenger.com/cc/index.php?topic=44869.0


Offline Chryco Psycho

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Re: driveline vibration help
« Reply #18 on: September 16, 2008 - 03:22:39 AM »
I just check the angle between the driveshaft & diff , you want to be %8 nose down on the diff , more will make a vibration decellerating , less will vibe accllerating

Challenger - You`ll wish You Hadn`t

Offline MyMopar

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Re: driveline vibration help
« Reply #19 on: September 16, 2008 - 10:06:34 AM »
I just check the angle between the driveshaft & diff , you want to be %8 nose down on the diff , more will make a vibration decellerating , less will vibe accllerating

So I would be better adding more diff pinion down? than using a shim plate to bring the transmission up.  I currently have 6* of wedge shims and really don't feel comfortable adding any more. 
I don't plan on pulling the axle and rewelding the spring perches until this winter.  The vib is not bad until highway speed then it is noticeable but gets wicked bad by 110 or so and if I cruise around town it really isn't noticeable.
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline Moparal

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Re: driveline vibration help
« Reply #20 on: September 16, 2008 - 11:07:18 AM »
maybe pull 2 degrees out of your wedges to 4

Offline ShelbyDogg

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Re: driveline vibration help
« Reply #21 on: September 16, 2008 - 11:27:11 AM »
Balance your wheels and tires.
Rob

3 E-bodies, Megasquirt-1v3.0, Edelbrock Pro-Flo-1, Holley C950, FAST EZ-EFI; say no to carbs...yes to throttle bodies

My Pace Car restoration thread:
http://www.cuda-challenger.com/cc/index.php?topic=44869.0


Offline Chryco Psycho

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Re: driveline vibration help
« Reply #22 on: September 16, 2008 - 11:30:51 AM »
try rottaing the tires & watching , I have seen BFG junk with more than 1/4" step in the tread where the belts overlap when brand new .... good qc  :banghead:

Challenger - You`ll wish You Hadn`t

Offline MyMopar

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Re: driveline vibration help
« Reply #23 on: September 16, 2008 - 01:09:28 PM »
maybe pull 2 degrees out of your wedges to 4

Well I ran 4* of wedge then added 2* more to get where I am at.  As a recap I was at +2* of rear pinion angle, added 4* wedge and it put me at -2*.  Added 2 more degrees of wedge and it put me at -4* of rear pinon angle.

The trans angle is -5* so I would think making a plate to raise it to a neutral 0* would do the trick for me giving me the difference I'm after.  I don't know, probably shouldn't even worry about this now anyway seeing how the driveline will be pulled for a small block set-up.  I do know this, the vibration was bad enought ot cause the rear pinon seal to start leaking  :banghead:  There goes my dream of a drip free car.
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline Aracer

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Re: driveline vibration help
« Reply #24 on: September 22, 2008 - 12:55:08 AM »
the difference between the drive shaft & diff should be 5-7* nose down on the diff
:iagree:
 Tell that to Moser, they think it's nose up. Watch out for them. The tranny to drive shaft should be 2* angled up, compared to itself only and the opposite on the rear, plus 4* shims =6* @ drive shaft. You need to subtract the floor angle to read the carpenters gravity angle gauge correctly.
     Have the drive shaft balanced with new rear Spicer Dana solid U-joint, and swap zerks for Allen set screw at the trans yoke u-joint, which may not accept solids due to the larger size center body.   
« Last Edit: September 22, 2008 - 01:06:42 AM by Aracer »