Is this a clutch going out???

[MillerR]

Sorry if this is the wrong place for this post. Just pulled my 5th wheel this last weekend for the first time in 9 months. 1st & 2nd gear are kinda' jerky starting out. The whole truck jumps around quite a bit. Everything seems to smooth out once up to speed. Shifting doesn't seem to be a problem. I've had clutches in the past, but I've never gone through one, so I'm not sure if I know the symptoms of one going out. Any suggestions? U-joints seem to be ok.

 

[bighammer]

Usually it starts slipping in the higher gears first. I think moisture or lack of use (rust) can make it grabby. I would guess if your pilot bearing is gone and everything is off center, it might cause that too.

I'm no expert, but Peter at South Bend Clutch could answer your questions best. When and if I need a replacement, it will be one of theirs.

 

[MillerR]

Thanks... Yeah, there didn't seem to be any slipping, just a big vibration at low RPMs in the first two gears and only if I tried to really give it some power, increasing the load. If I babied it, I didn't get any vibration. Could the Carrier Bearing be causing this? Like I said before, it's been 9 months since I pulled my 5th wheel, which is about 18k miles. Maybe the bearing is getting soft??? Any other ideas. I'm taking the truck in to have them look at the AC, so I'll probably have them check out this vibration also, but it doesn't seem to do it un-loaded. Thanks again for all inputs...

 

[MMeier]

Sounds more like a carrier bearing then a clutch IMO.

 

[jelag]

What your describing to me is a clutch that is chattering..... starts doing this under load... . I see it most of the time when trying to back up... . The quality of the friction isn't the best in the stock clutch and it can do that...

Also some of the performance frictions will do the same thing when they hook up...

We suggest the following in the lower gears... . to start the truck on flat level road you engage the clutch with no throttle... letting the torque and HP of the engine at idle pick up the load of the truck and trailer... once the clutch is fully engaged you apply power and shift... . This is actually the way the clutch and truck are designed to function.....

We see a lot of customers in our HD line try to add power... . as they engage the clutch..... this does cause problems... maybe you've seen a semi next to you almost pitch the cab off the chassis when they apply power... .

Their trucks are designed the same way... . and should be powered up the same way... thats the way they were designed to function...

If you can't live with this way..... as its now glazed over... your only choice is to change it... .

My trucks pulling 22K trailers average 100K miles on a clutch... . so if your under a 100K and don't tow much I'm guessing you've got lots of clutch life left.....

Hope this helps. .

 

[MillerR]

Thanks for the replies. Actually, I'm just over 100k at with the towing being probably less than 15k. Up until recently, the trucks been my daily driver, so most miles are from trips to work and back. I'll try using less power on take-offs. Like I said, it's going in to have the AC looked at, so I'll have them take a look at teh clutch as well. Thanks again... -Trey