2nd Gen Non-Engine/Transmission Gear Grinding ETH

[HCuervo]

Need help from someone who understands the manual transmission NV5600

(ETH): we have a 2001 2500 Sport with the 6 speed manual shift (it's the wife's truck). It has about 68 K miles and started to grind the gears when going from 3rd to 4th or when downshifting from 4th to 3rd - only.



There is no grinding when shifting any of the other gears, including 1st or reverse.



The grinding always happens when you are in a hurry to shift (merging traffic). If you wait a little, you can shift without grinding. Unfortunately, sometimes you want to shift quickly and it grinds.



Is this a clutch problem or a synchronizer problem? Is this a common problem?

I want to get it fixed with the extended warranty, but need a diagnosis.

Thanks!

 

[Oil Burner]

It's very common. Unfortunately, it is most likely the synchros. I don't think I have any left in 3rd gear. I get a wicked grind upshifting or downshifting to 3rd.



Mine has always been notchy going into 3rd even when new off the lot. It's worse now, but I try to drive around it. I really don't think anyone else could drive it right now without grinding.



Mine has 102k and I don't plan on fixing it anytime soon. Good luck with the extended warranty. I just changed fluid again and looking through the PTO cover, leading edge of the gears really doesn't look too bad at all.



Jason

 

[HCuervo]

Thanks, Jason.



I suspect it is the synchro and not the clutch.

 

[AggieJustin]

I've got the same thing, although the grind occurs going into 5th. I've learned to drive around it... but it will still show up if I get too carried away shifting.

 

[Nyoest]

Be very careful about neglegant maintenance, I had just bought my 01 used and was tickled pink with it but always had a little trouble getting it into 6th. After a week I was used to shifting pretty good. A day after that my 6th gear syncro grenaded and lodged in between two gears locking up the trans and drivetrain. This happened in my driveway, thankgoodness, backing up . it could have been a lot worse. $1,800 later at the dealer and I had a great shifting transmission But at least I had their cheezy 30 day warranty :-laf



It's like the fuel pressure gauge, you know it's a problem why put it off?

 

[C. Harlan]

I got a 6 spd from Blumenthal's, got it out of the crate, put it in, and have never had a 2nd gear synchro. . kind of stinks, but you learn to drive around it! Now Reverse synchro is gone as well. if I put it into first then go to reverse, all is fine, no grinding! Oh well, just thought I would chime in!



-Chris-

 

[Silver_Ram]

Change the trans fluid

I have noticed with my truck, it's starts the same grinding, just as you described when the trans fluid needs to be changed.



If you do alot of stop & go driving, you may have to change it every 12, 5000 to 15,000 miles.

 

[Ted Constantine]

I have a lot of trouble normally down shifting mine but no trouble at all if I double clutch. I always double clutch anyway as I have a couple vehicles without syncros. I agree that changing the fluid on these trannies makes a huge difference.

 

[metal tech]

Here's my . 02. Mine was a little tough to shift brand new, dealer said it's "normal". I run RP Synchormax which has helped. I have found that when upshifting, clutching while still on the throttle lightly helps it slip into gear much easier. Downshifting works better for me when I blip the throttle then push into gear.

 

[HCuervo]

Grinding Gears

Wow, I had no clue there was so much grinding going on out there. We are taking the transmission apart tomorrow and will report back with a pathological diagnosis. This is nothing more than exploratory sugery. All comments are well received and I can appreciate the need for changing the transmission fluid frequently. We did.

Thank you all, more to follow.



HCuervo

 

[Mhannink]

I just changed fluid again and looking through the PTO cover, leading edge of the gears really doesn't look too bad at all.



Jason

first id like to clear up a common misconception u don't grind the gears in the transmission the gears never move there is a collar(no syncro shown)on the out put shaft these engage the slected gear the grinding happens hear where the dog teeth on the collar engage a gear which the hooks it directly to the output shaft the layshaft is where u get ur rations from as far as griding it cause of the quick shift the syncro bad or just not very good is not meshing the gear properly when u try to shift and u end up pushing thro it while shifting slow allows the engine to mesh w/o the use of the syncro just as if u where doing it w/o the clutch what u can do when u downshift is raise the rpm up till it slides into gear its best for the clutch and trans anyways a good transmission fluid will help but changing it often will not cause there virtually no contaminets in it besides it has no filter idk what dc says about changing it and would go w/ what they say tho our 99 450 ford psd 6spd has never had any trans problems in 130k and im almost positive we never changed the trans fluid anyways i hope that helps in understanding what goes on i side there there should be a pic of a 5sp trans in this tell me if there isn;t so i get it on here im not sure how to yet so that would help too also a better discription of how a trans works is at http://auto.howstuffworks.com/transmission.htm

 

[JEccles]

This started happening to me recently (only down shifting into 3rd) i thought it was my clutch (needed a new one anyways after putting in the dd2's) so i put a new one in. it still continued to be a problem so i changed out the fluid (red line MTL) and after some miles it started shifting better across the board but you still had to be carful with third, as time passed it got better and better and now its no problem.