Attention: TDR Forum Junkies 
I've had a noise (see the end of this thread for details) in the drive-train for a long time. I first noticed it when the truck had around 3,000 miles on it. The noise seemed to get louder over time and eventually leveled off around 10,000 miles. The service department wasn't sure what it was, we went on several test drives with different mechanics and even went out once with the original service manager. No one would say it was a normal noise, most thought it would take more investigation to find out exactly where the noise was coming from. They drove other trucks on the lot and did not hear the noise. A regional technician was scheduled to go on a test drive with me but that sort of fell through the cracks, not of my doing. All fluid levels were checked, there is no evidence of lubricant leaks anywhere on the truck except for the hose replacing the blow-by bottle. I installed the Mag-Hytec cover on the rear axle and replaced the original synthetic with Almasol LE607 oil. The folks at Mag-Hytec swear by the stuff. It's kind of sticky and looks like it would not get thrown off as easily as the OEM fluids. This change had no effect on the noise.
Since the noise seemed to level off and nothing was falling off as I drove it I sort of let it slip to the back burner as priorities go. As I get close to the end of my 36,000 mile bumper to bumper warranty it's starting to cause me some concern. I realize the transmission should fall under the 5 year/70,000 mile warranty. I guess it's me worrying that it might be some obscure $20 part that's not covered under the drive-train warranty but will cost several hundred dollars to replace.
The interesting thing is when I had the truck in for service the last time (around 30,000 miles) the new service manager (dealership bought by Lithia behemoth) boldly stated the noise was perfectly normal, they all do it, and there's nothing wrong with the truck.
The noise: it sounds like the drive-shaft or some drive-line component is ringing. The "ringing" is very easy to hear when driving in 4th gear, engine turning 1000 to 1200 rpm with little of no load on the drive-train. Imagine driving down a level city street at 30 mph or so. If I open the door while driving (or if the mechanic opens the passenger side door) the noise is impossible to miss. As I slowly accelerate the noise seems to diminish. I can't hear the noise at freeway speeds.
The truck was built in August, 2001 but has the larger clutch. I know the early NV5600 transmissions had some sort of problem with bearings or shafts(?) but can't remember the details. When I bring this subject up with the service department I get a blank stare, shoulder shrug, and the "we don't know of any issues with that transmission". Last year while waiting for the truck to get serviced I actually saw the DC tsb and it mentions needing a 20 ton hydraulic press to fix the problem. I just wish I could remember what they were replacing.
Based on my limited troubleshooting the noise would appear to be coming from:
1. drive shaft (u-joints, center bearing assembly)
2. transmission (I need to do more research to see if it happens in all gears)
3. pilot bearing in flywheel (I understand this part fails quite frequently)
4. clutch and/or pressure plate
I don't think it's the throw-out bearing since pushing in or letting out the clutch doesn't have anything to do with the noise and when it occurs.
I spend a good deal of time in these forums and can't remember ever seeing a post on this problem. Anyone have any ideas?
Since the noise seemed to level off and nothing was falling off as I drove it I sort of let it slip to the back burner as priorities go. As I get close to the end of my 36,000 mile bumper to bumper warranty it's starting to cause me some concern. I realize the transmission should fall under the 5 year/70,000 mile warranty. I guess it's me worrying that it might be some obscure $20 part that's not covered under the drive-train warranty but will cost several hundred dollars to replace.
The interesting thing is when I had the truck in for service the last time (around 30,000 miles) the new service manager (dealership bought by Lithia behemoth) boldly stated the noise was perfectly normal, they all do it, and there's nothing wrong with the truck.
The noise: it sounds like the drive-shaft or some drive-line component is ringing. The "ringing" is very easy to hear when driving in 4th gear, engine turning 1000 to 1200 rpm with little of no load on the drive-train. Imagine driving down a level city street at 30 mph or so. If I open the door while driving (or if the mechanic opens the passenger side door) the noise is impossible to miss. As I slowly accelerate the noise seems to diminish. I can't hear the noise at freeway speeds.
The truck was built in August, 2001 but has the larger clutch. I know the early NV5600 transmissions had some sort of problem with bearings or shafts(?) but can't remember the details. When I bring this subject up with the service department I get a blank stare, shoulder shrug, and the "we don't know of any issues with that transmission". Last year while waiting for the truck to get serviced I actually saw the DC tsb and it mentions needing a 20 ton hydraulic press to fix the problem. I just wish I could remember what they were replacing.
Based on my limited troubleshooting the noise would appear to be coming from:
1. drive shaft (u-joints, center bearing assembly)
2. transmission (I need to do more research to see if it happens in all gears)
3. pilot bearing in flywheel (I understand this part fails quite frequently)
4. clutch and/or pressure plate
I don't think it's the throw-out bearing since pushing in or letting out the clutch doesn't have anything to do with the noise and when it occurs.
I spend a good deal of time in these forums and can't remember ever seeing a post on this problem. Anyone have any ideas?
