I was workign on my IROC tonight. Had it sitting at idle for 15-20 minutes while I adjusted the IAC and TPS after swapping in a new throttle body.

When I went for my test drive, I could not get the tranny to shift into any gears. It wasnt grinding but I wasnt giving it much force. I could tell something was stopping me and could feel the car try to move. With the motor off it shifts just fine. With the motor back on and in gear I can feel the car is trying to move.

Is this pointing to my slave/master clutch cylinder? I checked the fluid and its still full. Ive had no signs at all of clutch problems till tonight.

 

maybe a bad pilot bearing..

 

Check to see if your clutch reservoir is full, and check the master cylinder, slave cylinder, and the line for leaks. If there are none, I would think the pilot bearing as well. That went bad on my dad's F150 once, and when you turned the key, the starter would actually move the car even with the clutch pedal on the floor. To shift, you would have to turn the car off, because it wouldn't go in or out of gear with the car running.

 

Now your scaring me. The clutch and roller pilot bearing have maybe 6000 miles on them

 

Bummer... It is the pilot bearing .. It's locked up on the input shaft of the trans.. When you installed it did you install it flush to the crankshaft ? It should stick out about an 8th of an inch or more. For some reason it matters if it is installed to far.. Mabe goes up against a taper of something.. But anyway it is a pilot brg and it's not that hard to do really. I bet it's spun in the crank and it will fall right out when you pull eveything apart.

 

I hate when people say they know exactly what it is without looking at the car. I had the exact same problem with my t-5. In my case, the ball that the fork pivots on backed itself out, and was causing a reduction in the amount of fork travel. The car wouldnt grind, but it wouldnt go into gear. When shut off, it popped in with no problem. Im not sure if the set-up on the t-56 is the same, but I would definently check that. Mine has an allen head slot, and the whole thing threads into the flywheel. I also think that the pilot bearing is supposed to be flush mounted. Do a search. I've gone through all of this on here. I heard all the same stuff, pilot bearing, throwout bearing, clutch, slave cylinder. You have to just take the time and eliminate them. The pivot ball was very easy, so do it first.

 

Put it in gear, push the clutch in, give the car gas, and if it moves you know the clutch isn't completly disengaging. Then go from there.

 

CHECK THE CLUTCH FORK

 

That is not correct, If the pilot brg is trying to attach itself to the input shaft of the trans the car would act like the clutch isn't disengaging. The splines on the clutch disc slide onto the input of the transmission. When you push in the clutch it allows the input to run free from the engine. if the pilot binds it keeps it in gear.
If the clutch feels right it probley is working right.

Here is a test. Car off put it in gear and start it with the cluch in and a foot on the brake. See if you can break it free. If it was a bronze bushing it would spin it either in the crank or on the trans. and break free. Becarefull with the roller, it may eat up the trans shaft because that isn't a very soft metal. That's why I chose to stay with the bronze bushing.

As far as people knowing something with out looking at the car. It's true. I'm here and he's not but I do get paid a pretty good chunk of change for my knowledge. If it was a bronze bushing I know for sure the pilot brg doesn't sit flush, now the roller I am not positive but it should ride on the input shaft of the trans in the same area that the bronze bushing does. I have had many cars with pilot problems causing just what you are explaining. Not just a hey my car did this or that. I've been a tech longer than a lotta people on this board are old. But regardless, it's gotta come out unless you find the trans is falling out or something. Besides it's easy.. pull it and check it out.

 

Actually I didnt go with the roller that I bought because I heard bad things. I forgot about that. I installed it 2 years ago.

Ill check out the hydrolics tonight and if they check out then Ill dig in and check out the pilot bearing. I just dont understand how that could have gone bad so quick . The hydrolics were the used ones I got with the tranny. Clutch, pressure plate, bearings, etc were all new.

What is the actual function of the pilot bearing? I thought it jsut gave the shaft a place to mount. I dont understand its function with engaging/dis-engaging the clutch.

 

If you know it's a bronze bushing.. Start it with your foot on the brake, clutch in and in gear. If it's the pilot it should free it up atleast to know what the problem is.

 

Well I tore it apart over the weekend. It looks like the pilopt bearing may have seized to the shaft. The shaft is fine but the pilot bushing has some metal bent out of the hole.. hard to described but its not the way it should be....

Also found a toasted clutch with a broke spring. Ill be replacing it all.

 

Your thoughts about the function of the pilot are correct. It does keep the trans in perfect alignment but it's actually the input shaft of the trans that it keeps centered. The input shaft is what the clutch disk splines up against so when you push the clutch in the disk runs free from the engine as does the whole input shaft run free. Now sieze it to the pilot and push in the clutch... The clutch disk is free but the input shaft isn't.. So it its still basicly engaged...

 

Thanks for the details... Makes sense now. I shall be back on the road this weekend. Had to order a new clutch and of course a new pilot bushing is going in.

 

Pilot depth.. pic right outta chevy power catalog