ZF5 Question

[Diesel Max]

I've just started to notice a noise comming from my transmission in all gears while driving and in nuetral with the clutch released. Not really a "whine" sound but more like a "grinding" sound or a bearing spinning real fast with no lubrication. It only seems to be there when the clutch is released with it in gear driving or the clutch released in nuetral. If you push the clutch in a couple of inches while idleing and in nuetral, the sound goes away as well as if you push the clutch in driving down the road the noise stops.

There are no noises at all when the clutch is depressed. The truck runs and shifts fine and the clutch is not slipping. You can't really hear the noise from outside the truck but it's fairly noticeable inside the truck with the windows rolled up. Truck has 147K on it and I'm not sure of the history since i bought the truck about 6 months ago. The fluid is clean and was changed about 8K ago. No leaks of any kind.

Any ideas ??????????

 

[snicklas]

Throw Out Bearing? Since the noise goes away with your foot on the clutch, the TOB is not spinning, but does with no clutch pedal pressure......

The cluch guys will be along shortly to chime in, but that is my first thought......

 

[towcat]

Throw Out Bearing? Since the noise goes away with your foot on the clutch, the TOB is not spinning, but does with no clutch pedal pressure......

The cluch guys will be along shortly to chime in, but that is my first thought......

scott-
you're dead on.
throwout bearing is slowly committing suicide.

 

[Diesile]

Yep. In that setup there is always a little pressure on the t/o bearing so it is constantly
in motion, I believe.

 

[IDIDieselJohn]

Surprised mine ain't dead yet, been doing it for a couple years now, and the Dual Mass Flywheel is knocking louder than an old Chevy 305!

 

[SparkandFire]

Surprised mine ain't dead yet, been doing it for a couple years now, and the Dual Mass Flywheel is knocking louder than an old Chevy 305!

I had a 305 in my first car (an 81 el camino) what a POS that thing was!!!

And, yes, it knocked... had a lifter or two tapping away, one day it quit tapping... pulled the engine apart, pulled the cam out and found two flat lobes.

Pick-n-pull got that car!

 

[IDIDieselJohn]

I had a 305 in my first car (an 81 el camino) what a POS that thing was!!!

And, yes, it knocked... had a lifter or two tapping away, one day it quit tapping... pulled the engine apart, pulled the cam out and found two flat lobes.

Pick-n-pull got that car!

I bought brand new in 1978, a '78 GMC half ton auto. with a 305. It started knocking after 8,000 miles. Exact same thing that happened to your '81. Dealer fixed it, back on the road, and another 10,000 miles later, brought it back for the same thing.

Pulled it out and put a 350 in there, totally different truck!!

 

[Diesel Max]

Thanks for the info...............

Whats the average life expectancy once it starts making noise and will it cause any serious damage if I drive it a little longer ???

 

[towcat]

Thanks for the info...............

Whats the average life expectancy once it starts making noise and will it cause any serious damage if I drive it a little longer ???

hard to say how long it will last, but when it goes, you're stranded.

 

[jwalterus]

my truck was purchased with the whine, sounds like a real quiet loose alternator belt right??

I have a new TB and clutch fork behind the seat, and I have been driving mine for 1500 miles

 

[hesutton]

What can help that TOB stop the noise is to pull the slave cylinder, pull the clutch fork and reach in there and lube the TOB by hand. I know...... not easy, but difference will likely amaze you. It would be great if there were grease zerks on those suckers, but there isn't.

Heath