I have a '78 GMC pickup with a 3-speed manual tranny and add-on floor shift. After a bout with a snow drift, I developed a scraping, clanging sound in the clutch area. The sound isn't there all of the time, but it's getting more frequent. Nothing's loose on the linkage or anywhere else. There's no clutch slippage during driving. I can park the pickup, put the gear shift in neutral, and still get the sound when I rev the engine. However, when I depress the clutch and rev the engine there's no noise. I'm guessing it's something to do with the clutch or pplate. Maybe a loose clutch spring. I first thought I'd bent the shifter linkage, but it just doesn't sound like a transmission gear grinding. Any ideas?

Although someone might be able to help out in this section, you might want to ask the same question in this area of the forum...

http://texasfishingforum.com/forums/ubbthreads.php/forums/32/1/Tow_Vehicles_Auto_Discussion

Throughout bearing going bad?

Throwout bearing sounds like the place to start.

Thats what I was thinking as well

I would put money on the throwout bearing being bad. You can get a clutch pretty cheap for you truck nowadays, if i were going to go thru the trouble, i would do it all while i was in there. May even get the flywheel turned too.

There is one more thing that just occurred to me.

CLUE: "After a bout with a snow drift.."

Isn't there a thin sheet metal shield under the bell housing? Something could have wedged inside, during the bout with the snow drift. Look under it and see if it's bent. I bet it is.

Tiny rocks and debris can hit the flywheel and make it sound like it's coming apart. I seem to recall that happening to me on a 64 Chevy once. In fact, I think that piece of tin hit the flywheel on mine. It should come off with 4 small bolts.

Take a look.

i would but on a bent dust shield also. speaking of trans trouble, i gotta replace me clutch master cylinder soon...

Problem solved--on the road again.
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Transmission was the problem and the flywheel was also slightly damaged. I'd let the tranny run low on gear oil and when I got stuck it shelled some bearings. $330.00 bucks gone that would have been better applied to beer, bait,
and tackle.