Clutch questions

[RoadstarDallas]

I have a 1999 Freightliner FLD with Detroit and Rockwell 10 speed. My clutch is engaging near the top of the pedal travel and I'm wondering if it's time for a new one or are there any adjustments to this type of setup? I have had the truck for a little over a year, 862k miles and don't know when it was last done. Any thoughts or guidance would be greatly appreciated.

[JoeyB]

If you haven't touched the clutch in a year, it's a safe bet it just needs adjustment.

While I've been out of the shop for a while now, I've never seen a non-adjustable clutch, unless it's shot and has nothing left to adjust. There are self-adjusting jobs now, too. I don't have any experience with those, but if they work anything like auto-adjusting slack adjusters, well, you get the point. You'll have to adjust it manually anyway...

[solo379]

I also, would suggest a reputable shop, for that job, to do it properly, not just linkage. I usually do my 2-3 times a year, at a CAT dealer.

[Kranky]

I have a 1999 Freightliner FLD with Detroit and Rockwell 10 speed. My clutch is engaging near the top of the pedal travel

URGENT ATTENTION REQUIRED HERE!!!! IMMINENT CLUTCH DESTRUCTION LIKELY IF NOT ADJUSTED ASAP!!!

Clutch adjustment is not a big deal.

If you decide to adjust it yourself, just be sure to do the adjustment INTERNALLY at the adjuster on the pressure plate.

Never adjust the external linkage to compensate for normal clutch wear.

To adjust:

Remove the inspection cover at the bottom of the flywheel housing.
look up in there to see what position the adjuster is at, then turn the crankshaft til the adjuster is at the bottom near the inspection hole.
(I use a socket & breaker bar on the retaining bolt on the harmonic balancer on the front of the crankshaft to rotate it)

Have an assistant depress the clutch pedal to the floor & hold it down.
(The adjuster will not turn unless the clutch is disengaged)

Put a 5/8 box end wrench on the adjuster hex head & push in the locking collar.
Pull the wrench toward the drivers side to increase free travel (actually turning the adjuster clockwise)

Adjust it about a 1/4 turn then check free travel, adjust this way til you have 1 1/2 to 2 inches of free travel.

Be sure the locking collar has popped back out to lock the adjuster, (you may have to rotate the adjuster a little one way or the other til it locks)

Thats it!

WHILE YOU'RE IN THERE GREASE THE THROWOUT BEARING!

Some have a fitting on the bottom of the throwout bearing, others have a hose from the bearing attached to a grease fitting in the inpection cover, whichever kind it has, put in about 10 pumps of a good quality #2 grease, it's very important to keep the throwout bearing lubricated.

Now replace the inspection cover & you're good to go.

Never let a clutch adjustment "run tight" (no free travel), or the clutch will soon start to slip and self destruct.

[bob h]

I have a 1999 Freightliner FLD with Detroit and Rockwell 10 speed. My clutch is engaging near the top of the pedal travel and I'm wondering if it's time for a new one or are there any adjustments to this type of setup? I have had the truck for a little over a year, 862k miles and don't know when it was last done. Any thoughts or guidance would be greatly appreciated.

clutch adjustment should be done as the pedal free travel starts to disappear. I.e. - if there's no free-play, you need a clutch adjust.

how does your clutch brake work?

you need to measure your clutch release travel;
use the male end of a 1/2" drive extension, or the head of a 5/16" bolt (both measure a 1/2" across. place the 1/2" tool between the release bearing and clutch brake... if it fits loosely, the clutch is out of adjustment (9/16" max).

if the clutch is out of adjustment, use the procedure explained by splitshifter to adjust (his example is for a spicer easy pedal, most clutch designs are similar)... this will adjust the release travel.

the free travel should equal 1/8" in between the clutch release fork finger and the wear pad on the releae bearing... this should result in about 1 1/2" free pedal depending on the chassis.

if you find this clutch has a spring loaded mechanism where the adjuster should be, it may be a self adjusting clutch.

also, if it has a tab that moves through a long, arced slot or groove in the clutch cover (labelled "new" at one end, and "replace" at the other end of the slot), it is also an auto adjust clutch.

remember; as the clutch friction lining wears, the pedal free play goes away.

[RoadstarDallas]

Thanks very much for the replies, I'll get it adjusted right away. The clutch brake hasn't worked very well either and I've been meaning to get it worked on for a while. Thanks again for the help!

[JoeyB]

[quote="bob h"]

use the male end of a 1/2" drive extension, or the head of a 5/16" bolt (both measure a 1/2" across. place the 1/2" tool between the release bearing and clutch brake... if it fits loosely, the clutch is out of adjustment (9/16" max).

Yeah, I always used a long 5/16" hex-head bolt as a guage. I'd adjust it until the head of the bolt just fit, and then leave the clutch alone until wear caused the gap to get big enough to allow the bolt head to spin- that would be 9/16". Just an easy way to check it.

There are actually 3 seperate adjustments to make, although you should seldom if ever have to mess with #2 or 3. They are:

1-The pressure plate itself- to adjust for normal wear The main thing you should worry about here is getting the 1/2" gap we're talking about.

2-The linkage, to adjust the clutch brake so it compresses the clutch brake disc when the pedal is about 1" or less from the floorboard. If #1 and 2 are correct, you should have the 1 3/4" free-play you want. if not, you probably have some bent linkage parts or there's a small possibility someone has goofed with the pedal stop under the dash- so you might need to do #3

3-Set the pedal stop under the dash (if it's adjustible).

The important thing is to be accurate with your adjustments and follow the steps IN ORDER. You'll have a real nice clutch when you're done.

[bob h]

* when the free travel is properly adjusted (1/8" between release fork and release bearing);

you should be able to place a 0.010" blade-type feeler gauge between the clutch brake and transmission (input bearing retainer). depress the clutch pedal to the floor, and then you should NOT beable to pull the gauge out.

this procedure verifies clutch brake squeeze (ensures that you are not grinding your way into 1st and reverse at a standstill), and also verifies that the internal and external adjustment were both done correctly.

[RoadstarDallas]

Had the clutch adjusted at the TA shop in OKC, clutch and clutch brake are now working great and total cost was $32.99. I printed the instructions for the next time and will do it myself. Thanks again for everyones' help.

[allan5oh]

I printed the instructions for the next time and will do it myself.

No you wont, you need two people :P

[bob h]

I printed the instructions for the next time and will do it myself.

No you wont, you need two people :P

hey 5oh, it sure makes the job easier!

make sure the keys are out of the ignition when your hands go inside the bell housing

...my favorite spot for keys?....... in MY pocket!


many times, i've used my long prybar between the clutch pedal and seat...

...if there's no one around, you find a way ;0)