tom woods 1310 read drive shaft vibration
12-29-2014, 10:58 AM
#31
JK Jedi Master
update, I took the rear DS off to get a more accurate measurement and found the rear is at 7 degrees as the Transfer case is at 8 1/2.(the close up pic of the angle finder is the TC) I then drove the Jeep and the slight vibration was not there. I re-checked both the pinion nut and TC nut torque and both are good.
My question for you is would 1 1/2 degree cause this slight vibration I am feeling from 25-35 mph only under acceleration?
It is a very slight vibration that only I can notice, Would Upper adj. CA be necessary to prevent future damage?
any help is appreciated.
My question for you is would 1 1/2 degree cause this slight vibration I am feeling from 25-35 mph only under acceleration?
It is a very slight vibration that only I can notice, Would Upper adj. CA be necessary to prevent future damage?
any help is appreciated.
It sounds like you are comparing the angle at the t-case to the angle at the pinion.
The t-case angle is of no concern, (within reason, of course).
It's the angle at the pinion you need to get as close to zero as possible. The difference between the line of the pinion axis, and the line of the drive shaft axis, needs to be less than 3°, preferably 0°.
This is all because you have a double cardan at the t-case, with a single cardan at the pinion.
The joints in the double cardan cancel each other when they are displaced from straight.
When the single joint at the pinion isn't straight, it throws it's inherent vibration into the drive shaft, without another joint to cancel it out.
Cross type u-joints speed up and slow down twice with each revolution. That's a source of vibration when you don't have an even number of properly indexed and aligned u-joints on a shaft.
Last edited by ronjenx; 12-29-2014 at 11:07 AM.
12-29-2014, 11:07 AM
#32
JK Jedi Master
http://www.4x4wire.com/tech/pinionangle/
12-29-2014, 11:07 AM
#33
It sounds like you are comparing the angle at the t-case to the angle at the pinion.
The t-case angle is of no concern, (within reason, of course).
It's the angle at the pinion you need to get as close to zero as possible. The line of the pinion axis, and the line of the drive shaft axis, need to be less than 3°, preferably 0°.
12-29-2014, 11:09 AM
#34
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It sounds like you are comparing the angle at the t-case to the angle at the pinion.
The t-case angle is of no concern, (within reason, of course).
It's the angle at the pinion you need to get as close to zero as possible. The difference between the line of the pinion axis, and the line of the drive shaft axis, needs to be less than 3°, preferably 0°.
This is all because you have a double cardan at the t-case, with a single cardan at the pinion.
The joints in the double cardan cancel each other when they are displaced from straight.
When the single joint at the pinion isn't straight, it throws it's inherent vibration into the drive shaft, without another joint to cancel it out.
Cross type u-joints speed up and slow down twice with each revolution. That's a source of vibration when you don't have an even number of properly indexed and aligned u-joints on a shaft.
The t-case angle is of no concern, (within reason, of course).
It's the angle at the pinion you need to get as close to zero as possible. The difference between the line of the pinion axis, and the line of the drive shaft axis, needs to be less than 3°, preferably 0°.
This is all because you have a double cardan at the t-case, with a single cardan at the pinion.
The joints in the double cardan cancel each other when they are displaced from straight.
When the single joint at the pinion isn't straight, it throws it's inherent vibration into the drive shaft, without another joint to cancel it out.
Cross type u-joints speed up and slow down twice with each revolution. That's a source of vibration when you don't have an even number of properly indexed and aligned u-joints on a shaft.
Holy Hell my pinion angle is at 7 and I need to be at 0? Will just adj. uppers take care of this? Or will i need the lowers too?
12-29-2014, 11:11 AM
#35
JK Junkie
Sometimes a picture...
You want the dif pointed directly at the drive shaft or 1 or 2 degrees lower as it does rotate up a little under load.
You want the dif pointed directly at the drive shaft or 1 or 2 degrees lower as it does rotate up a little under load.
Last edited by 14Sport; 12-29-2014 at 11:23 AM.
12-29-2014, 11:16 AM
#36
JK Jedi Master
(Like in the photo 14Sport posted, above.)
12-29-2014, 11:23 AM
#37
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https://www.youtube.com/watch?v=JgmXg5EIF8w I watched this hence why I was trying to match the TC and Pinion angle. I will be purchasing adj uppers tonight. I can't stand this annoying vibration
12-29-2014, 11:30 AM
#39
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Like this?
I put the angle finder on both ends of the DS and the measurements are the same
12-29-2014, 11:31 AM
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