NV4500 (or clutch) vibration

[Archive]

Howdy gents,

I usually post on the 1st generation site, but I upgraded my gearbox a few years back to an NV4500 found in your vintage trucks.

My question is regarding a slight vibration when starting off in 1st gear under load (horse trailer). Halfway through the clutch release, I get a slight squeeky vibration that lasts about a second. After the truck is under way, no problems.

All u-joints in the driveline were recently replaced, so I'm pretty sure I don't have a problem there. I'm thinking more about the throw-out bearing. Has anyone had any similar problems?

Any help would be much appreciated.

Thanks,

 

[Todd T]

It sounds like you are right.



if you are at idle, does it chatter any? or if you leave it in neutral and press on the pedal until it just comes into contact with the pressure plate do you hear then?



you could be getting some squeaking from the bearing retainer if it has dried out. or if the grease caked up with dirt.

 

[Archive]

No chatter at idle, but if you are on a slight incline and you let the clutch out, the gearbox makes a slight vibration. To complicate matters, it doesn't happen all the time and only when starting off in 1st gear.

I guess I'll take it in and have someone look at it.

Thanks for the help,

 

[jrobinson1]

I have a vib in first also also first OD (have aux box). Also does it in reverse. I haven't heard the squeak. Have always assumed it was a slightly uneven pressure plate.



My thought, haven't looked into it though. no load start up in higher gear ratio allows more slip and you don't notice the uneveness. I was supicious i got grease on my clutch last time I replaced the pilot bearing.





james