Driveline Vibration

gtsfirefighter

SM Expert on White trash
Sep 26, 2006
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gaboonviper85;1432135 said:
A trans won't cause ungodly vibrations no matter what's wrong...it's either broke without question or smooth as ever!

Did you have the ds balanced after you replaced the rear section?

No I didn't and couldn't have if I wanted as the new carrier bearing is shot now and most likely was before putting that other rear shaft on.
No worries though, I bought a one piece from Shaftmasters. The sent me one too long and as soon as I called David to tell him, they made me another and shipped it same day, so it should be here early this week.

sparkplug619;1435803 said:
what happened to the pics? I was about to show this to someone and the pics magically disappeared

Which pics? I'm at work and picture hosting websites are blocked so can't tell.
 

Grandavi

Active Member
Sep 25, 2008
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Calgary, Alberta, Canada
I am curious..

A. is there an aftermarket place that sells these specifically for the Supra (the single shaft)

B. is there any caveats to having one constructed? (weight and balance really shouldnt factor in as long as the length and strength are sufficient is my guess)

C. Why is it constructed this way in the first place? Seems to me to be flawed engineering unless there was a specific reason to it.

D. Can you repair this yourself (with a vice and a busterbar)

I have a vibration when I drive that has been driving me buggy the last 2 weeks but the car is being parked for some body work and winter, so I will check this.

Many thanks for this post. It is a good eye-opener!
 

sparkplug619

2 Supras, 1 Paycheck =[
Sep 28, 2008
285
0
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San Diego California
Grandavi;1436270 said:
I am curious..

A. is there an aftermarket place that sells these specifically for the Supra (the single shaft)

B. is there any caveats to having one constructed? (weight and balance really shouldnt factor in as long as the length and strength are sufficient is my guess)

C. Why is it constructed this way in the first place? Seems to me to be flawed engineering unless there was a specific reason to it.

D. Can you repair this yourself (with a vice and a busterbar)

I have a vibration when I drive that has been driving me buggy the last 2 weeks but the car is being parked for some body work and winter, so I will check this.

Many thanks for this post. It is a good eye-opener!


http://www.driveshaftshop.com/
 

gtsfirefighter

SM Expert on White trash
Sep 26, 2006
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Well I ordered a steel single piece driveshaft from Shaftmasters. The first one they sent was too long. I called David and they made a new one and shipped it the same day. I got it today, and it bolted up with no issues. I then take it for a drive and the initial response was awesome. However, when I reach 50-55 mph, I begin to get a constant vibration that feels like a constant deep bass hum and when I let off the gas to coast the vibration is ten times more harsh than what it was before. I put it in neutral and still had the vibration. After 55 mph it is constant, unlike before.

Now, first off, I am NOT bashing Shaftmasters. David has offered exceptional service. I've got an email into him with the same above information. My question to yall is...Is there anything else that could be causing this or do I just have an out of balance shaft? If it is out of balance, I have no doubt that David will do right by me. I really wished there was someone local who could drive my car and tell me what the fuck is wrong. I'm seriously becoming "disenfranchised" with this car and am about ready to throw a For Sale sign on it. The process of elimination that I'm going through is becoming very expensive.

So any insight would be helpful and much appreciated.

Kenneth
 

gtsfirefighter

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Sep 26, 2006
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IJ.;1438927 said:
Checked the backlash in the Diff yet?


While the car was up on jack stands and the new shaft attached, I put the car in park and tried moving the wheels back and forth. There was virtually no slack to be felt and if there was it was less than 1/4 inch. My car has 145k miles on it. So it felt pretty tight. I do still get that grinding feel somewhat when taking off in a turn, never when taking off straight forward. It is much less with the new shaft, but I do still feel it a little.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Jack it up in neutral park brake on firm and see if you can move the driveshaft, then park brake off and turn the shaft and see if you can feel any harshness in the front diff bearings.
 

mecevans

Supramania Contributor
Jan 18, 2009
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M-bay, cali
balance those wheels? half shafts? diff? im betting it might be a bearing. my uncles maxima has sealed for life bearings but the races or something is jacked up. gets a hum like you describe after 65.
 

gtsfirefighter

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Sep 26, 2006
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IJ.;1438935 said:
Jack it up in neutral park brake on firm and see if you can move the driveshaft, then park brake off and turn the shaft and see if you can feel any harshness in the front diff bearings.


I'll have to do that tomorrow when I get home from work. How much play, if any, am I looking for for it to be considered bad?
 

IJ.

Grumpy Old Man
Mar 30, 2005
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gtsfirefighter;1438942 said:
I'll have to do that tomorrow when I get home from work. How much play, if any, am I looking for for it to be considered bad?

I'd say anything more than 1/32 of a turn would be "bad", but the condition of the pinion bearings will determine how stuffed it is Ken. (I've killed 2 sets)

If the old 2 piece was out of phase it's more than likely hammered the pinion bearings into submission.
 

Victor Charlie

Supramania Contributor
Aug 18, 2009
161
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Ann Arbor
Thank you IJ. I have this too, vibration on highway after clutching, and even more when coasting in neutral, so thanks, I have some things to check.

Anyone have info on that question about what the purpose of the 2 piece drive shaft design might have been? Most mods seem to have trade offs, so I wonder if there is any disadvantage to a one piece driveshaft?
 

Victor Charlie

Supramania Contributor
Aug 18, 2009
161
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0
Ann Arbor
IJ.;1438974 said:
Shorter shaft sections raise the critical speed of a driveshaft, it's "smoother" for longer.

Ahh, of course. It raises the intrinsic harmonic frequency of each section, just like a shorter pendulum string. Thanks.
 

shaftmasters

Vendor
Oct 29, 2007
95
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michigan
www.shaftmasters.com
gtsfirefighter;1438925 said:
Well I ordered a steel single piece driveshaft from Shaftmasters. The first one they sent was too long. I called David and they made a new one and shipped it the same day. I got it today, and it bolted up with no issues. I then take it for a drive and the initial response was awesome. However, when I reach 50-55 mph, I begin to get a constant vibration that feels like a constant deep bass hum and when I let off the gas to coast the vibration is ten times more harsh than what it was before. I put it in neutral and still had the vibration. After 55 mph it is constant, unlike before.

Now, first off, I am NOT bashing Shaftmasters. David has offered exceptional service. I've got an email into him with the same above information. My question to yall is...Is there anything else that could be causing this or do I just have an out of balance shaft? If it is out of balance, I have no doubt that David will do right by me. I really wished there was someone local who could drive my car and tell me what the fuck is wrong. I'm seriously becoming "disenfranchised" with this car and am about ready to throw a For Sale sign on it. The process of elimination that I'm going through is becoming very expensive.

So any insight would be helpful and much appreciated.

Kenneth


Ken,
We did want to let you know that out of all the Supra single piece shafts we have sold. We have never had a situation like yours. We do not sell 10% as many Supra shafts as we do Nissan 240SX and 300Zx shafts but it is still between 100-150 that we have sold. This includes aluminum shafts and steel shafts like yours. Single piece shafts with no center bearing and no rear "rubber element" section will tend to show differential vibrations as more pronounced. The "hum" on acceleration and vibration on coast and decel that you have described to us does make us want to say "pinion bearings". But, check it out and if you need to send the shaft back we will of course honor our "money back guarantee".
Thanks, David
 

gtsfirefighter

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Sep 26, 2006
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shaftmasters;1439231 said:
Ken,
We have never had a situation like yours.

I've heard that a lot. Why do I always have to be the first. :biglaugh:
Now I feel obligated to find/fix the issue for the sake of all supra owners.

I'm nowhere near ready to throw that shaft in a box and send it back yet.
Ok, back to the garage to jack the car up and crawl underneath it...my favorite place to be.:: facepalm ::


BTW David, I caught your email before this.