Clutch pedal vibration

[Petegraintrain]

Just replaced my clutch because I thought that would fix this issue. But it's still there. Basically my clutch pedal vibrates/pulsates when it's pulling. It's the most noticeable when i put my foot on the clutch pedal and remove some freeplay. So it must be coming from the engine. What would cause this? The higher my rpms get the worse it seems to get.

2015 Peterbilt 389 with a cm570 signature 600.
Clutch is a brand new Eaton 2050

[Nostalgic]

Did you happen to check runout on your flywheel? It's normal to feel some pulsation/vibration with your foot is resting on the clutch pedal taking up the freeplay, but if it's hitting really hard, something is off somewhere.

[Petegraintrain]

(01-14-2023 )Nostalgic Wrote:  Did you happen to check runout on your flywheel? It's normal to feel some pulsation/vibration with your foot is resting on the clutch pedal taking up the freeplay, but if it's hitting really hard, something is off somewhere.

yea the runnout was within spec.(don't remember the numbers) I'll run it for a bit and see if I think its excessive I guess

[Bengy88]

(01-14-2023 )Petegraintrain Wrote:  

(01-14-2023 )Nostalgic Wrote:  Did you happen to check runout on your flywheel? It's normal to feel some pulsation/vibration with your foot is resting on the clutch pedal taking up the freeplay, but if it's hitting really hard, something is off somewhere.

yea the runnout was within spec.(don't remember the numbers) I'll run it for a bit and see if I think its excessive I guess

It could be a problem from your transmission you are feeling. Sometimes a bad gear or bearing shows up first in the clutch pedal. Are there any abnormal noises or any rattling while you are idling? Do your mirrors shake excessively? Also as nostalgic mentioned it could be your head messing with you…. We all do it. Some reman clutches or cheaper lines of clutches tend to have a vibration or rattling.

[Nostalgic]

(01-14-2023 )Petegraintrain Wrote:  

(01-14-2023 )Nostalgic Wrote:  Did you happen to check runout on your flywheel? It's normal to feel some pulsation/vibration with your foot is resting on the clutch pedal taking up the freeplay, but if it's hitting really hard, something is off somewhere.

yea the runnout was within spec.(don't remember the numbers) I'll run it for a bit and see if I think its excessive I guess

There's flywheel face runout, concentric runout, and then checking runout against the outer face of the flywheel housing - not sure if it's a different term, it's been a while since I looked it up. My old block had the crank at an angle. Just on the edge of spec, but it was enough to really feel when resting the forks against the throwout bearing. I could feel a rolling thump from it, but only in 12th gear for some reason.

[Petegraintrain]

(01-14-2023 )Bengy88 Wrote:  

(01-14-2023 )Petegraintrain Wrote:  

(01-14-2023 )Nostalgic Wrote:  Did you happen to check runout on your flywheel? It's normal to feel some pulsation/vibration with your foot is resting on the clutch pedal taking up the freeplay, but if it's hitting really hard, something is off somewhere.

yea the runnout was within spec.(don't remember the numbers) I'll run it for a bit and see if I think its excessive I guess

It could be a problem from your transmission you are feeling. Sometimes a bad gear or bearing shows up first in the clutch pedal. Are there any abnormal noises or any rattling while you are idling? Do your mirrors shake excessively? Also as nostalgic mentioned it could be your head messing with you…. We all do it. Some reman clutches or cheaper lines of clutches tend to have a vibration or rattling.

My transmission was a little wore out. Nothing crazy just a bit of howling in certain gears stuff like that. So I went and replaced it with a genuine eaton 2050 at the same time and it hasn't seem to make a difference. Maybe it's in my head. I don't know. Just don't want to break my crank in half due to excessive vibration from one thing or another

[tree98]

Is the clutch fork adjusted properly? I had this "pedal vibration" issue on 2 trucks in the past. Both had clutch forks that were out of adjustment by quite a bit.
They are only supposed to be 1/8" from the throw out bearing. It is adjusted by lengthening or shortening (lengthening if the gap is greater than 1/8") the linkage rods that attach the pedal to the clutch fork.
By the way both the trucks I had problems with, came this way from the factory....... WAY out of adjustment.

[Bengy88]

(01-15-2023 )tree98 Wrote:  Is the clutch fork adjusted properly? I had this "pedal vibration" issue on 2 trucks in the past. Both had clutch forks that were out of adjustment by quite a bit.
They are only supposed to be 1/8" from the throw out bearing. It is adjusted by lengthening or shortening (lengthening if the gap is greater than 1/8") the linkage rods that attach the pedal to the clutch fork.
By the way both the trucks I had problems with, came this way from the factory....... WAY out of adjustment.

when you adjust a clutch you adjust the release bearing to a 1/2 inch gap between bearing and clutch brake then you adjust 1 1/2 inches of free play in your pedal by lengthening or shortening the rod that goes from the pedal to the clutch arm. On a hydraulic clutch you just set your 1/2 inch gap and no other adjustments are needed

[tree98]

I believe that 1-1/2 inch of free play comes from the 1/8" gap between the fork and bearing.