BigRedWeather
Full Access Member
In August (it is 11/8/09 now) I put a new clutch kit and SMF in my truck and have spent lots of time, money and effort getting a very bad vibration out of the truck. Turns out that the cause of the vibration was the least expensive part in the clutch kit- the Kevlar Pilot Bushing. Here are two posts that have discussed the issue prior to knowing the cause:
http://www.oilburners.net/forums/showthread.php?t=32690&highlight=Vibration
http://www.oilburners.net/forums/showthread.php?t=33790&highlight=vibration
South Bend automaticalyy ships the Kevlar PB with every clutch and sings their praises. When the first clutch kit gave me all of the vibration, after 1000 miles I pulled the clutch and the Kevlar was wallowed out just a little bit. South Bend sent me a whole new kit at their cost. I put that clutch in and ran it for 4000. When it had the same vibration I took it to a good diesel shop that installs a lot of South Bend Clutch. When they pulled the transmission the Kevlar PB fell out of the flywheel because it had been beat around so much. The first time I posted this I failed to mention an important thing. The shop said we had slightly damaged the PB when we put the transmission in. That sounds real strange because she slid in like a charm. I tend to think the horrific vibration of the shaft is what damaged the PB. There is a ring that goes on the back side (i.e. toward the rear of the truck) of the flywheel that the 10 flywheel bolts go through. The owner of this shop, who is a fine mechanic himself, said the ring was its proper place when they pulled the transmission.
The front bearing on the transmission was damaged by the vibration so it had to be replaced. (The transmission shop got their wires crossed and rebuilt the whole transmission
. Charge to me $150 ) When they put the transmission back in they used a needle pilot bearing. ALL VIBRATION IS GONE. How sweet it is. Now I can accelerate up through 3000 RPMs on each gear if I want/need to, without loosing my teeth.
This is my assessment of what happened. 1st replacement clutch and Kevlar PB allowed the shaft to vibrate, because the Kevlar couldn't hold it still. Driving on it for 1000 miles loosened the Kevlar PB but not enough to damage the front bearing on the transmission. 2nd replacement Kevlar PB that I drove for 4000 allowed the shaft to move around and cause the vibration. Since I drove it for 4000 this time it damaged the front bearing on the transmission. If the Needle Pilot Bearing caused problems I will surely post them here.
One other tid bit, and I think I have posted this on this forum. After the 1st and 2nd clutch kit were pulled out, the throw out bearings have been coming apart. South Bend called in Luk and Luk said it was performing as designed. I expect when I pull this current throwout bearing (hopefully in 3 years and 100,000 miles) it will be damaged in the same way. I just hope it doesn't fall apart even further.
The cost of gaining experience is very high.
BigRedWeather
http://www.oilburners.net/forums/showthread.php?t=32690&highlight=Vibration
http://www.oilburners.net/forums/showthread.php?t=33790&highlight=vibration
South Bend automaticalyy ships the Kevlar PB with every clutch and sings their praises. When the first clutch kit gave me all of the vibration, after 1000 miles I pulled the clutch and the Kevlar was wallowed out just a little bit. South Bend sent me a whole new kit at their cost. I put that clutch in and ran it for 4000. When it had the same vibration I took it to a good diesel shop that installs a lot of South Bend Clutch. When they pulled the transmission the Kevlar PB fell out of the flywheel because it had been beat around so much. The first time I posted this I failed to mention an important thing. The shop said we had slightly damaged the PB when we put the transmission in. That sounds real strange because she slid in like a charm. I tend to think the horrific vibration of the shaft is what damaged the PB. There is a ring that goes on the back side (i.e. toward the rear of the truck) of the flywheel that the 10 flywheel bolts go through. The owner of this shop, who is a fine mechanic himself, said the ring was its proper place when they pulled the transmission.
The front bearing on the transmission was damaged by the vibration so it had to be replaced. (The transmission shop got their wires crossed and rebuilt the whole transmission
. Charge to me $150 ) When they put the transmission back in they used a needle pilot bearing. ALL VIBRATION IS GONE. How sweet it is. Now I can accelerate up through 3000 RPMs on each gear if I want/need to, without loosing my teeth.This is my assessment of what happened. 1st replacement clutch and Kevlar PB allowed the shaft to vibrate, because the Kevlar couldn't hold it still. Driving on it for 1000 miles loosened the Kevlar PB but not enough to damage the front bearing on the transmission. 2nd replacement Kevlar PB that I drove for 4000 allowed the shaft to move around and cause the vibration. Since I drove it for 4000 this time it damaged the front bearing on the transmission. If the Needle Pilot Bearing caused problems I will surely post them here.
One other tid bit, and I think I have posted this on this forum. After the 1st and 2nd clutch kit were pulled out, the throw out bearings have been coming apart. South Bend called in Luk and Luk said it was performing as designed. I expect when I pull this current throwout bearing (hopefully in 3 years and 100,000 miles) it will be damaged in the same way. I just hope it doesn't fall apart even further.
The cost of gaining experience is very high.
BigRedWeather
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) I have no problems thus far.
