Driveshaft runout spec
Thread Starter
Instructor
Joined: Dec 2006
Posts: 115
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From: Metro Detroit
Driveshaft runout spec
Hi,
I was searching the archives for a definitive number on the max. allowable runout of the propeller shaft inside the torque tube but could not find a good answer.
If anyone has the shop manual, maybe you could help me out.
Mine (2000 A4) came out at 0.014" and I'm not sure if this is acceptable or not.
Thanks
Alex
I was searching the archives for a definitive number on the max. allowable runout of the propeller shaft inside the torque tube but could not find a good answer.
If anyone has the shop manual, maybe you could help me out.
Mine (2000 A4) came out at 0.014" and I'm not sure if this is acceptable or not.
Thanks
Alex
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Joined: Apr 2011
Posts: 3,332
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From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11-'12, '14-'15-'16-'17-'18
Hi,
I was searching the archives for a definitive number on the max. allowable runout of the propeller shaft inside the torque tube but could not find a good answer.
If anyone has the shop manual, maybe you could help me out.
Mine (2000 A4) came out at 0.014" and I'm not sure if this is acceptable or not.
Thanks
Alex
I was searching the archives for a definitive number on the max. allowable runout of the propeller shaft inside the torque tube but could not find a good answer.
If anyone has the shop manual, maybe you could help me out.
Mine (2000 A4) came out at 0.014" and I'm not sure if this is acceptable or not.
Thanks
Alex
If propeller shaft runout exceeds 0.3 mm (0.118 in), the propeller shaft is bent and should be replaced.
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Pro
Joined: Aug 2010
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From: San Antonio Texas
Just curious. Where is the measurement taken? If the shaft is in the torque tube I would imagine that you could only access the shaft rotating in a very small area near each end? If it is that close to the ends where it attaches how would you know if it was bent? I have to say that 0.014" runout is pretty small on that diameter. Any idea how the shaft was made? Welded ends? Just curious.
Supporting Vendor
Joined: Apr 2011
Posts: 3,332
Likes: 195
From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11-'12, '14-'15-'16-'17-'18
Just curious. Where is the measurement taken? If the shaft is in the torque tube I would imagine that you could only access the shaft rotating in a very small area near each end? If it is that close to the ends where it attaches how would you know if it was bent? I have to say that 0.014" runout is pretty small on that diameter. Any idea how the shaft was made? Welded ends? Just curious.
Pro
Joined: Aug 2010
Posts: 593
Likes: 9
From: San Antonio Texas
From the OP's original statement I thought the measurement was taken with the shaft inside the TT. The runout reading is a total error of the tube diameter and the straightness of the shaft depending on how the centerline datum was established. I would still say that 0.014" is pretty darn good for a measurement at the middle of a shaft that long sitting on bearings. Very interesting. I guess the assembly is dynamically ballanced as well in two planes?
Supporting Vendor
Joined: Apr 2011
Posts: 3,332
Likes: 195
From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11-'12, '14-'15-'16-'17-'18
From the OP's original statement I thought the measurement was taken with the shaft inside the TT. The runout reading is a total error of the tube diameter and the straightness of the shaft depending on how the centerline datum was established. I would still say that 0.014" is pretty darn good for a measurement at the middle of a shaft that long sitting on bearings. Very interesting. I guess the assembly is dynamically ballanced as well in two planes?
The drivehshaft is balanced from the factory but don't know if it's in two plains.
Thread Starter
Instructor
Joined: Dec 2006
Posts: 115
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From: Metro Detroit
There are 2 issues:
1. 0.3mm is not 0.118 but 0.0118! It must be a typo in the manual since 0.118 is about 3mm and that would be visible.
I also informed myself about the runout specs for other RWD high performance vehicles and their specs are around 0.008 for high speed operation.
2. This might explain the vibration i have in my drivetrain despite replacing the rubber bushings which I suspected first.
BTW, I measured the shaft in the middle (on v-blocks at the ends of the shaft)
I guess its time for a new driveshaft.
Thanks,Alex
Last edited by Alex99; May 26, 2012 at 11:42 AM.
