I just put a new clutch kit and hyd. line in my 88 f250 5 speed 4X4. after installing everything and bleeding numerous times I still have a low pedal. And before the replace the pedal would spring back up after a shift. Im also experiencing new noises. If im just sitting in neutral and push the clutch in and release it I can hear a clunking/light grinding noise. Also when i shift, if the rpms are above 2000 the gears grind pretty bad but after they are in it stays and runs ok. I checked the slave against a new one from advance auto and they both moved and felt the same so I did not replace it. the only thing left is the master cylander but there are no leaks. It is the only thing left to check besides firewall flewould that be causing these problems). Could there be something wrong with the pedal assembly. I checked and it looked like everything was ok.Thanks for any help.

 

did you get ANY oil onto the clutch plate, flywheel, or pressure plate? if you did that, it sounds like the clutch is slipping like none other. also did everything work right before? or did you just have a low pedal?

 

No, I made sure the clutch was clean before install. What happend was, one day I got in my truck and pushed the clutch to start it and the pedal just thumped to the floor. so I brought it back up with my foot and tried to press it again and it was so hard i couldn't press it. So like a jackass i just pushed really hard and it blew the line off the slave below. Well, i figured that something was binding to cause the line to blow so i put a new kit in and put it back together. that was the only reason for the replacement. pedal was fine before. I always had the grinding when shifting though. this all happened the first day i brought the truck home. i picked it up and drove for about 350 miles home. right after i was home the line blew.

 

well, the pedal was probably because the throwout bearing was binding on something, and couldnt travel.

the clunking grinding noise is when the clutch is pressed? or is it when pressed and then you let off the pedal?

 

when you bleed the clutch its backwards. get under the truck open the bleader push the rod back in to the slave cylinder, hold while you tighten the bleeder. Make sure the pedle is puled up when you start. The master cylinder dosent hold a lot of fluied,be sure to fill it often.

 

I had some trouble with the bleeding also, when I replaced the clutch in my F350 crewcab over Xmas. But here is how I ended up doing it:

Open bleeder on slave cylinder.
Push pedal to floor.
Close bleeder.
Pull pedal up manually.
Add fluid to resivoir.
Pump pedal with foot a few times.
Double check fluid level.

The grinding noises and clunking is the transmission itself, and there can be several causes.

First possibility, the new clutch bites significantly better than your original worn clutch, so there is no slipping. This means that 99.9% of the engine torque is passing through to the transmission putting a load on the gears and bearings, which is not the case with an older, worn clutch.

Second possibility, and more likely, is that the alignment of the transmission's input shaft and the crankshaft is now skewed, from you seperating the two in order to replace the clutch. So the way it was originally installed, might be 0.05" off axis one way, and now that it's reinstalled, it might be 0.05" the other way, making for a 0.1" misalignment. Which, if the input shaft front bearing is warn a bit as is likely with a higher mileage truck, is enough to cause the gears inside to clunk, chatter, grind a bit, et al if the syncros aren't spiffy new.

 

nighthawk, yes the noise is heard when you after you let the clutch pedal back up. Im bascially bleeding the clutch like a brake system...pump it up, hold pedal down, crack bleeder, close bleeder repeat...with two people of course. Is that correct?

 

well thats how i did mine, and it seems to work fine.

my manual says if it makes a squeal or rumble with clutch fully engaged (pedal released), then the throwout bearing is binding on the transmission bearing retainer.....remove clutch components and check bearing remove any burrs or nicks, clean and relubricate bearing retainer before installing.

if it only does it once the clutch is pushed in and then brought back up, its probably something in the clutch....if it does it before the clutch is pushed in as well, then I'd go with Frederics description, and its something in the tranny...

 

I checked the throwout bearing before putting everthing back together ad it looked ok. Why do you think the pedal wont come the whole way back up? sounds like the clutch is not disengaging the whole way.why do you think its making the noise when the clutch come back up. It only makes the noise on full release of the pedal. Do you think the master cylander could be losing some pressure? Or maybe something else wrong with it. thanks alot for the help.

 

according to my manual here, it says that when "Clutch pedal stays on floor when disengaged"

that 1:Linkage or release bearing binding. Inspect the linkage or remove the clutch components as necessary
or 2: Make sure proper pedal stop (bumper) is installed

so since you have no linkages, either the throwout bearing is binding on something, or the pedal stop in the pedal bracket itself somehow fell out or something

question though....did you lubricate the inside of the throwout bearing where it moves on the shaft?

 

Yes i lubed the bearing. I just found thepaperwork that was in the clutch box and it is saying something about there being clearence issues with my tranny case and the 11 inch clutch disc. It said something about if you had a zf and it was a reman case then you will have clearence issues at a certain point in the case...it gave a picture...it said just open it and grind out a quarter inch where it says and it will be fine. ever heard of this? does this sound like a possibility? thanks again

 

can you post that paper?

 

I cant sorry i dont have a scanner...I'll see what i can do. have you ever heard of that problem?there was an 11 inch LUK clutch that came out of it..i dont get why this one wouldnt work.

 

if it says that its probably going to have clearance problems, thats probably what your problem is, see if you can use a scanner, or find it maybe online and we'll see what happened.....or you can just take it out again.....

if its having clearance problems, you will be able to see right where when you take the trans off.....just look around where that picture said, and there will probably be wear marks of some kind.....grind it down, and it sounds like it should be fine

 

Im gonna check it and see but if the pressure plate was hitting the case wouldnt it always make a scraping noise? also would that cause my pedal to be low?