I am getting a strange clutch behavior and wonder if this has been seen before (I hope).


I drive along, everything is fine, then I go to push the clutch pedal in and it's nearly on the floor, like an inch (maybe) from the floor. It still seems to "work" ok, I can disengage and engage it but the whole travel motion is in the 1" from the floor! Usually the pressure point is way up to the top. It stays like this for a minute or two, and then seems to go away all on its own. It's done this 3 times to me in the last 2 days. Once the pedal snapped back up to the top while driving after it was on the floor reengaged.


It seems to have something to do with getting onto it hard (slipping the clutch maybe?). I have a VA150 box, stock clutch still. I have had this box for a few months now, never had this kind of problem before. The one thing I did the last time I changed the oil, like maybe a month or so ago, was to add a little DOT-4 fluid to the clutch reservoir since it was down a little. I have seen a bunch of posts regarding DOT-3 vs DOT-4. The top of the reservoir says to use DOT-4, so that's what I used.


I am gussing my clutch is finally going and it's starting to slip more, although I don't notice it (i.e. I don't see the tach go up w/o the kick in the pants feel from the wheels moving along w/ it).


I need to get my new flywheel & clutch in but now I am concerned there may be something wrong with my slave/throw-out assm. Is there any way to check this out once I have the tranny out of the truck?


Is this the infamous "hard pedal" I have heard people talk about? I always thought the hard pedal was where you drive down the highway and after several hours you stop at an exit and the pedal is extremely hard for several clutch dis/engagements but not like what I am getting now. I mean the clutch pedal stays on the floor practically and even will snap back up after going (did this once).


Thanks,


Tim

I had this problem last summer. My family was on vacation and we were pulling our 29' TT for about 4 hours. We stopped for a bite and I got back in the truck, my clutch went almost to the floor, except for about the last 1". Scared the crap out of me. Went on down the road and for the next few shifts, the clutch acted the same way. While on the highway awhile, it fixed itself. Did this one or two more times on the drive down. Has never done it since!


A lot of help that is...sorry! FYI...that was after my factory DMF was replaced.


MaxRock

You're overpowering the clutch.

I used my Edge Juice for almost a year with no issues and I was somewhat skeptical of the folks reporting these symptoms on their stock clutches, since mine always worked fine. But for the last month or two, mine's been doing this too. And it's getting worse ... it started as just a power level 5 issue in 6th gear, now I can induce it at will at any power level over 1 in either 5th or 6th gear. And that's empty. Pulling the trailer I have to leave the Edge at power level 0.

South Bend Clutch (http://www.southbendclutch.com) has Kevlar, Kevlar/ceramic, and pure ceramic clutch discs for them that will supposedly hold more torque than the stockers. I'll be installing one soon, alonf with the new DMF.

I was afraid that was the answer. MaxRock, do you have a power box? Was wondering if you had this problem on a stock truck?


I have a new kevlar clutch & SMF flywheel still in the box, I need to break down and find the time to install it I guess, not a job I am looking forward to...


Thanks,


Tim

I had the problem on a stock truck. No power adders, just pulling my 29' TT at the time. Trailer weighed in around 7k pounds.


I don't think I was slipping the clutch. When the clutch started doing this, the truck had been sitting for about 45 minutes and the problem cleared after driving for about 30 - 40 miles.


It felt like air in the hydraulic line. Wierd!!!


That was on the factory setup. The clutch has not acted like that since I had the DMF replaced...which the truck is going in for another replacement!!! http://www.dieselplace.com/forum/smileys/Angry.gif


MaxRockEdited by: MaxRock

mine did that also with no power add's, the dealer put a trany cooler on and not had a problem sence

Sounds like there's more than one thing that can cause this.

Possibly heat is the issue, slipping the clutch is just a way to induce heat quickly, there are others.

My truck has always had the hard pedal syndrome after sustained highway miles as well. It never tried to leave the pedal on the floor in that scenario, though.

Pumping the pedal several times seems to clear it up, regardless of what I did to get it messed up.

I am definitely slipping the clutch. In 6th, I can step on it, and see the tach cruise on up, immediately after that, it's a super hard pedal and when I push it in, it stays on the floor... :-( Looks like I better put my other honey-do projects on hold and get the new flywheel and clutch installed sooner than later. I have put it off for a couple of months or so now.


Thanks,


Tim

The clutch is not too bad to do. I would say 4 or 5 hours if it is the first time you have done it on your truck. CPMac can do a single in about 2 hours, but that is darn quick. The tranny is pretty well balanced so a floor jack works pretty well. Take the time to drop the T case off as it is much faster than taking the cross member out.

Those symptoms sound a lot like boiled fluid and air in the lines, just like a braking system.

Try bleeding the hydraulic clutch system and replacing the fluid with a high temp fluid. That's an inexpensive alternative and could push your clutch install off a bit if it works.

Hmmm...except I don't know where to bleed the system at.... http://www.dieselplace.com/forum/smileys/Ermm.gif

Gary
Sheehan Motor Racing
www.teamSMR.comEdited by: GarySheehan

Sounds like a good idea, what is hi-temp fluid? Guess I never heard of hi-temp DOT-4 fluid.


Tim