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Old 05-29-2015   #1
cadillac531
 
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Default Throwout Bearing???

Armed with my new fuel pumps and tires, I took the Beast for a little trip out of town last weekend. She ran like a champ, through the rain, and up the hills and mountains with the AC on and the cruise on, it pulled down 23.2 mpg. I was pretty happy, as this makes the ZR my most fuel efficient vehicle

Anyway, when I left my folks' house to come back home, the trans made a high pitched bearing-like sound just as the clutch engaged. It did it as I would engage reverse and as I would engage first. I took it around the block before heading on back, and when everything warmed up, the sound went away and didn't come back.

I started the car again today and it gave me the same sounds, I rocked the car front and back with the clutch and after the third time of doing this, the sound stopped and the clutch engaged quietly like usual.

Can anyone describe to me the sound a throwout bearing makes? The trans shifts fine, and there are not any other audible sounds other than the ones a ZF usually makes.

Thanks.
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Old 05-29-2015   #2
QB93Z
 
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Default Re: Throwout Bearing???

The sound you describe could be the pilot bearing. It is sometimes hard to differentiate between pilot bearing and throw out bearing noise.

In my most recent experience, the pilot bearing gave the symptoms you have. The noise would go away after the first few clutch operations. A bad throw out bearing doesn't usually get quieter.

Either way, the transmission and clutch need to be removed.

Jim
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Old 05-29-2015   #3
GOLDCYLON
 
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Default Re: Throwout Bearing???

#2 on the pilot bearing. Throw out bearing noise does not go away. Kinda like fidanza flywheel noise that only goes away when you enguage the clutch or while cruising
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Old 05-29-2015   #4
cadillac531
 
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Default Re: Throwout Bearing???

Thanks for the replies guys. I will drop the trans and get this all fixed up.
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Constantine

Registry Founding Member #0235

1991 Corvette ZR-1 -- Stock, 94 ZR-1 exhaust system, muffler delete.

1956 Chevrolet Belair -- Pro Street, 531ci Cadillac, 8-71 Blower, 8pt roll bar, built TH-400, 9" rear, 1,100 HP -- Street Car.
https://www.youtube.com/watch?v=z8y4cwcvK0s

1968 Mustang "Pegasus" -- Zeeker Chassis, 584ci Dart Block, Brodix Big Brodies, 2-1150 Dominators, FTI 'Glide, 1168 hp, best ET & Trap(holding back) 8.57@159 -- 7.9X -- 1/4 mile car.

1970 Chevelle -- 468ci, TKO600, shaved and smoothed everything.
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Old 05-29-2015   #5
XfireZ51
 
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Default Re: Throwout Bearing???

Use the brass bearing, not the needle bearing pilot. Fewer parts to go bad.
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Old 05-29-2015   #6
cadillac531
 
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Default Re: Throwout Bearing???

Quote:
Originally Posted by XfireZ51 View Post
Use the brass bearing, not the needle bearing pilot. Fewer parts to go bad.
Thanks for the reply. In a previous post I found, Mark Haibeck suggested this pilot bearing gm pn14061685 saying it won't come loose. Do you happen to have a part number for the brass one you suggest?

Thanks.
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Constantine

Registry Founding Member #0235

1991 Corvette ZR-1 -- Stock, 94 ZR-1 exhaust system, muffler delete.

1956 Chevrolet Belair -- Pro Street, 531ci Cadillac, 8-71 Blower, 8pt roll bar, built TH-400, 9" rear, 1,100 HP -- Street Car.
https://www.youtube.com/watch?v=z8y4cwcvK0s

1968 Mustang "Pegasus" -- Zeeker Chassis, 584ci Dart Block, Brodix Big Brodies, 2-1150 Dominators, FTI 'Glide, 1168 hp, best ET & Trap(holding back) 8.57@159 -- 7.9X -- 1/4 mile car.

1970 Chevelle -- 468ci, TKO600, shaved and smoothed everything.
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