Grinding sound, hard to get in gear - went away? (Page 1/1) 842m4SE OCT 19, 02:30 PM I recently made a 160 miles journey in my stock 84 without issue, the duke and the car ran great the whole way. Yesterday was my first time driving it since, and it was fine on the highway up until I got on the offramp, when it started making a grinding sound and I had to shove it into 1st gear, then going to the ramp to get back home, I had to shove it grinding into 3rd and then it went easier into 4th. On the offramp to my home, it wouldn't go into any gear, so I had to shove it hard grinding into first just to get it to limp back home. Double clutching didn't help. The clutch pedal felt and feels normal and the master cylinder is full of fluid, though a bit dark. I've replaced both the master and slave and ran about a liter of fluid through the system trying to bleed it about 4 months ago. Now the weird thing is after waiting about 20 minutes I tried driving it around the parking lot and it shifted just fine! Went into 1st, 2nd, 3rd without any weird sounds. The clutch fully disengages the gears, and with the engine on I can put in the clutch and go through all the gears without grinding or movement. Drove it about 10 minutes and it was just fine. I'm glad but very confused. I have to make the trip back on friday... I would prefer not on a trailer. Any help or advice is greatly appreciated. Gall757 OCT 19, 05:00 PM if it aint broke.....yadda yadda.. but it could be that dirt in the master cylinder is the problem, and it cleared itself. Patrick OCT 19, 05:07 PM How high does your clutch pedal sit above the brake pedal? It's possible you just barely have enough "throw" to disengage the clutch, and it therefore doesn't take much to prevent disengagement. Your slave should be moving about 1-1/8". Any less and you're courting disengagement problems. fieroguru OCT 19, 07:44 PM Air bubble in the clutch slave. When cool, the bubble is small and not very compressible so everything works like it should. Drive it for a while, the slave heats up which causes the air bubble to expand and become larger and more compressible, possibly to the point you no longer have enough travel to properly disengage the clutch. reinhart OCT 24, 05:14 AM quote Originally posted by fieroguru: Air bubble in the clutch slave. When cool, the bubble is small and not very compressible so everything works like it should. Drive it for a while, the slave heats up which causes the air bubble to expand and become larger and more compressible, possibly to the point you no longer have enough travel to properly disengage the clutch. If it's a Duke the slave is no where near the exhaust unless I'm mistaken. On a 6 the crossover is near the slave. fierofool OCT 24, 08:12 AM I agree with guru for heat causing bubbles. Isn't there a coolant hose near the fluid line, even on the Duke? I like to slide a length of ribbed wire loom over the fluid line to insulate it. Visit http://gafiero.org Message Board Club News 2021 Newsletter. There is a clutch bleeding article in this months edition. fieroguru OCT 24, 09:49 AM quote Originally posted by reinhart: If it's a Duke the slave is no where near the exhaust unless I'm mistaken. On a 6 the crossover is near the slave. The duke exhaust loops up and is within about 6" or so of the slave. However, I have seen this happen with HTOB applications on steady state cruise where the "slave" in inside the bellhousing and only subjected to normal engine/transmission operating temps. cvxjet OCT 24, 12:05 PM I just wanted to suggest checking your Trans fluid level...Also, when you get a chance, make sure you are using the GM Synchromesh-type fluid....You can buy it cheaper from a number of other companies (Pennzoil, etc) Greatly improved the shift-ability of my Getrag..... reinhart OCT 26, 05:34 AM quote Originally posted by fieroguru: The duke exhaust loops up and is within about 6" or so of the slave. However, I have seen this happen with HTOB applications on steady state cruise where the "slave" in inside the bellhousing and only subjected to normal engine/transmission operating temps. I stand corrected. It's been so long since I had a duke. It might be informative to feel the temperature of the slave cylinder when these symptoms present themselves next time.