Engine/Transmission (1994 - 1998) noisy nv4500

[rdrose]

i have a question about some noise in my transmission. the transmission is in a 97 with 180,000 miles. at around 160,000 miles the pilot bearing went out. no problem had a brand new clutch waiting to go in. while i had the transmission out I had a fully splind 5th gear shaft and a new input shaft and bearing put in. now when i release the clutch in neutral there is like a bad bearing noise. i had the transmission looked at and they didn't see anything that was bad. i know there is something bad in there i just need a clue what to look for. my question is what in there moves while turning in neutral and what should i look for? I also put a different clutch in to see if it was the clutch same noise.

 

[PaulG1]

By no means am I an expert - but have you checked the mainshaft endplay (clearance)?



A few questions:



1. Was the bearing "like" noise detected immediately after the rebuild or was it detected later?



2. Is the noise always there in all gears and at all rpm?



3. Does the noise peak in a specific gear at a specific rpm range?





Hopefully a NV4500 buff will chime in here.



Paul

 

[EGaskamp]

I'm no expert either, but if I had to take a guess I would have to say that it sounds like a throw out bearing or some call it a release bearing. I had the same noise in my NV4500 on my 95. I had a new throw out bearing put in and no more noise. Good luck, hope this helps.



Eric

 

[Deezul1]

I had the exact same experience. after the installation of the fully splined mainshaft I could hear whirring bearing noise when stopped in neutral. The trans shop said it was normal (dont ya get tired of hearing that BS?). After breaking 3rd gear and having it replaced the noise is gone, big surprise, they put it back together right this time.

 

[Jff24Gordn]

If you hold your foot lightly on the clutch, does the noise change?? If so, its the throw out bearing. If it dont change, its internal to the transmission. When the transmission is in nuteral, these bearigns are spinning... bearing on input shaft, main piolet bearing, main thrust bearing, counter shaft and bearings main bearings, 3rd gear needle bearings, 2nd gear bearings, 1st gear bearings, reverse gear needle bearings, reverse idler gear and bearings, 5th gear bearings, and the shift collar for 5th is spinning on the fork. Put it on jack stands and put it in each gear. If its quiet in one gear and not the others than its the bearings for that gear.



First thing to look for is shaft end play. Take off the PTO cover and grab a big old screwdriver and pry on the shafts, if the shafts move more than 0. 006" than it is out of spec. The gears on the main shaft will move back and forth a little on the shafts depending on the wear on the thrust washers. Form there on, it gets hard to find problems over the internet.

 

[rdrose]

sorry to take so long to answer but it's rough here in south fla. i told the transmission shop that they will get it back soon. i told them to look at the end play when they get it back out. unless anyone knows of a good transmission shop here in s. fla that knows these transmission. thanks jff24gordon for what moves in there. its not the throw out bearing it's in the transmission

 

[Gene Arnold]

I had a new Luk clutch installed two years ago when my throwout bearing went bad (old clutch was good but didn't want to have to tear it down twice). Since the new clutch, throwout bearing, and pilot bearing were installed, I get a "rattle" when things are hot and I'm idling in neutral. Goes away when I kick the pedal real quick or when I keep the pedal down. I think it is most likely the springs on the clutch disk (seems there was a thread on this some time back). It has a completely different sound from the one heard when the throwout bearing went bad. Could be the problem with yours.

 

[rdrose]

the noise goes away when i put the pedal to the floor but i also feel a vibration in the pedal. i've had two sbc and the same with both. i'm pretty sure it's in the transmission i asked the guy who put the my transmission together about the end play and he didn't remember if he checked i'm sure he didn't. i'm about tired of having my transmission in and out. 5th times the charm? i just need to find someone who know more about these transmission's.

 

[Coalsmoke]

the noise goes away when i put the pedal to the floor but i also feel a vibration in the pedal. i've had two sbc and the same with both. i'm pretty sure it's in the transmission i asked the guy who put the my transmission together about the end play and he didn't remember if he checked i'm sure he didn't. i'm about tired of having my transmission in and out. 5th times the charm? i just need to find someone who know more about these transmission's.

rdrose, did you ever figure out what the problem is? My transmission does the same thing, not getting any worse right now but it is a little un-nerving. thanks.

 

[Gene Arnold]

I responded to this thread (#7) when it first showed up and now I have some additional comments.



The previous install never was completely right. I had a little grabbing and a quite a bit of rattle at idle that would usually go away if I kicked the pedal a bit. Mid year 2005 my clutch got so grabby that I was afraid I was going to break something, especially when backing my trailer, so I took it to a reliable shop and had them do a clutch replacement. They ended up doing the complete clutch, throw-out bearing, pilot shaft bearing, and flywheel.



When the mechanic showed me the pilot bearing in the old flywheel it was nearly completely through the flywheel with perhaps a third of it still in and it was cocked at an angle! I think this caused insufficient support for the input shaft (not sure of the right term) thereby allowing the rattle when at operating temperatures and also was undoubtedly responsible as well for the terrible grabbing condition. I surmise that this condition was the result of faulty installation during the previous job.



New clutch (same brand) works like new.



Gene

 

[K5IP]

Input shaft and it's bearing.

Rog