Driveline vibe

[Forced4]

I hope someone can help me on this one. I have a distinct vibration at 40mph. It gets a bit worse at 45mph. Then it goes away slowly as I accelerate. I tried tire balance. I checked for bent rimes (3 of them). I took the wheels off and with the care in the air, I put the lugs back on to support the rotors. In any gear at 40mph the vibe is still there. I look at driveshaft. I do see a little vibe at the front third of the driveshaft. The other 2 pieces do not vibrate at all. The front carrier is vibrating slightly. Now, I have new carriers with the fix done as a preventitive action. I have marked the driveshaft and assembly was correct. All ujoints look good. No play up/down/side/side anywhere in the driveline. Is there any way the carrier bearing can be on crooked? I can't immagine it could. There is no visible damage to the driveshaft, but could it be bent?...only at one end?

Sorry for long post, I wanted to give as much info as poss.

P.S. the vibe was there but not as bad before the carrier bearings were done.

THANKS
Rich
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[HITNRUN]

I had this problem on a truck. I used hose clamps and put them around the driveshaft to balance it. Trial and error. I just put some clamps on the driveshaft and moved them around until the vibe was gone.

 

[Forced4]

I suppose that might help to diagnose the problem. Thanks.

I definitely will not keep it that way, however.

Rich
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[Defiant]

Carrier bearing is my guess.

 

[Forced4]

Originally posted by Defiant
Carrier bearing is my guess.

My fault... I replaced the carrier bearings about a month ago. I checked ujoints and all at that time as well. I would have guessed the same thing. But that's not it.

Thanks
Rich
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[Forced4]

So now I decided to replace u-joints. I do this and the vibe is worse. Now I get the same vibe at 40-50 but it's stronger, and I get one at about 20mph. Mind you I am testing this with the car in the air as to not have to drive and jack over and over. Does anyone know of a place in the Phoenix area that is capable of balancing these damn driveshafts? Dick's said no and Mesa Driveline said no. I don't know what else to do. I sure don't want to buy a used and likely bent or damaged driveshaft. I sure don't want to spend $1000 on a new assy from Mitsu. Driveshaft shop shows a listing for 92-94 but I have a 91 GSX. I sent them an email but I am looking for the most cost affective solution as I haven't even had a chance to do any mods I am still maintaining this old car.

Thanks
Rich
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[2GDSM95]

you should balance the whole shaft together if you take a 2 pec shaft apart and dont put it back together the same way you change the balance. take it to a drive line shop and have them balance it

 

[Forced4]

No one around here is capable of balancing a 3 piece shaft. It seams that with ALL the f'n DSM's ni the world and all the people that have had problems with driveline vibes, nobody has ever needed a drive shaft repair shop to work on one. (sarcasm is abound)
I have found a few complete shafts for about $175 ea. That is my last resort. I know that "I" have marked the shaft and put it back EXACTLY the way it came apart. What I don't know, is weather or not someone else has ever had it apart. Anyway, I still don't know what I'm going to do.

Thanks
Rich
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[2GDSM95]

Originally posted by Forced4
No one around here is capable of balancing a 3 piece shaft. It seams that with ALL the f'n DSM's ni the world and all the people that have had problems with driveline vibes, nobody has ever needed a drive shaft repair shop to work on one. (sarcasm is abound)
I have found a few complete shafts for about $175 ea. That is my last resort. I know that "I" have marked the shaft and put it back EXACTLY the way it came apart. What I don't know, is weather or not someone else has ever had it apart. Anyway, I still don't know what I'm going to do.

Thanks
Rich
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[2GDSM95]

well i work at a drive line shop and yes you can balance a 3 pec shaft most shop's balancer's are to old and they dont have the no how to do it. but yes it can be done

 

[2GDSM95]

Originally posted by Forced4
So now I decided to replace u-joints. I do this and the vibe is worse. Now I get the same vibe at 40-50 but it's stronger, and I get one at about 20mph. Mind you I am testing this with the car in the air as to not have to drive and jack over and over. Does anyone know of a place in the Phoenix area that is capable of balancing these damn driveshafts? Dick's said no and Mesa Driveline said no. I don't know what else to do. I sure don't want to buy a used and likely bent or damaged driveshaft. I sure don't want to spend $1000 on a new assy from Mitsu. Driveshaft shop shows a listing for 92-94 but I have a 91 GSX. I sent them an email but I am looking for the most cost affective solution as I haven't even had a chance to do any mods I am still maintaining this old car.

Thanks
Rich
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any time you change a u joint it will change your balance . some times you can get lucky and not get a balance but the only way to do that is marking the shaft and puting the shaft back together the same way.
there is a way how to balance the shaft but it is tricky you realy need to know what you are doing. but yes it can be done.

 

[Forced4]

Yes sir, I agree, it CAN be done. The problem is no one near me is compitant enough to do this. It's funny how everyone knows someone who knows someone, but they live far away. I apreciate your input. I am not convinced that it is a balance problem, but I haven't ruled it out yet. I will say this though, Before I ship this thing all over the USA and have people charge upwards of $200 to balance it, I will sell the car. I will not pay $800 for a "1 piece" shaft that is 2 pieces. I will not pay $1000 for a factory shaft from the dealer. I will simply sell the car. I have replaced many u-joints and NEVER had to rebalance a shaft. I'm not saying that it shouldn't be done, but simply, I have never had to.

Thanks again
Rich
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