03 NV5600 Hard to shift

[Kohl]

My 03 3500 dual 4x4 with 110K miles is starting to not want to let me shift up. Added short shifter with 25K miles on the truck.

The problem started with not wanting to go into 5th. It is as if something is blocking that slot. This problem is getting worse. It would not go into reverse one time. This problem seems to be or with 3/5 and R.

Now when shifting into 3rd I get a high speed gear grind more frequently. The synchronize seem to be "by-passed".



EDIT: I do have trouble at time getting it into gear. It acts up stopped as well as rolling down the road.



I am in central Florida near Ocala. Who knows of a good transmission shop?



I am planning on replacing the clutch since they will have to pull the transmission.



Having trouble justifying a new truck.



Help - guidance, suggestions.



Thanks.



John

 

[steved]

When was the last time you changed trans fluid?

 

[Kohl]

I changed with Amsoil at 80K.

 

[rscurtis]

I would look at the clutch first- a bad pilot bearing or a clutch that doesn't release all the way could be your problem.

 

[steved]

First thing I would do is change fluid again... 20k to 30k is when I typically start feeling the same issues you describe.



Did changing to Amsoil give you an intial better feel or same feel as the fluid it replaced? The NV5600 is very finicky and each one is unique in what fluid it "likes".

 

[steved]

I would look at the clutch first- a bad pilot bearing or a clutch that doesn't release all the way could be your problem.

If this was the case, it wouldn't go into gear (or will be very difficult) at a standing stop...

 

[GCroyle]

Basic clutch release test:



ENGINE OFF



1. Raise one rear wheel, support with jackstand. Saftey first.

2. Select any gear, trans stays in gear for entire test.

3. Two people required, one driver, one wheel man.

4. Driver presses pedal to floor.

5. Wheelman rotates wheel.

6. Observation: Can you spin the rear wheel easily?

7. While spinning rear wheel, slowly bring clutch pedal up, observe for initial catch point and observe for reserve travel of pedal prior to initial catch point.



This test may not pinpoint if you have a pilot bearing failure, still might release clutch but jamming in pilot bearing may still cause input shaft to rotate from pilot.



Pilot bearing failure has been noted at your mileage or less, can cause drag and difficult shifting. If you splines are rusty and not allowing the disc to slide on shaft, also causes shifting issues.



This test removes trans from equation and just looks at what the clutch is doing. Remember, the clutch really has no idea what gear you are selecting, it just turns the disc or not at your command.



Minimize pilot bearing wear by selecting N at lights when conditions permit, remove foot completely from pedal.

 

[GCroyle]

REVISION TO PREVIOUS POST



We usually do this on the rack with all wheels off of the ground and we turn the drive shaft by hand. Not sure how anti-slip diff will behave under same one wheel up test.

 

[steved]

I just went through this with a warped pressure plate in my NV5600... being the OP didn't state any issue getting into gear from a standstill, it sounds like a synchronizer issue which is likely related to the miles on the fluid.



In my experience with several manual transmissions (not limited to a NV5600), a bad throw-out bearing, warped clutch pressure plate, or bad pilot bearing will show up in all gears, not just 3rd and 5th. If the clutch isn't releasing (i. e. dragging) the transmission will be difficult to get into any gear from neutral at a standstill.



Being I have been there... start with a fluid change as its cheap and easy. Mine does the same thing once the fluid gets some miles on it... and its always just 3rd and 5th. New fluid typically makes all the difference... FWIW, I found Red Line MTL works the best in my particular NV5600.



FWIW, my OE clutch was replaced around 180k... all components were in good shape. My trans sits with 266k... it has always done the 3rd/5th thing with between 20k and 30k on the fluid, in fact; it is doing it now and I need to change fluid. I have ran Amsoil, Red Line, Royal Purple, and Pennzoil in this thing...

 

[Prairie Dog]

The hardest gears to get into is 3rd and 5th for me too. Seems to be somewhat the nature of the beast.

 

[CKESSEL]

My 5600 was tough to shift for awhile until the clutch assembly was replaced. The fingers at the edge of the diaphragm had flat spots worn in them causing the t/o to hang up and not operate properly at like 50k. Once replaced, no more problems.

 

[RVTRKN]

My 5600 was tough to shift for awhile until the clutch assembly was replaced. The fingers at the edge of the diaphragm had flat spots worn in them causing the t/o to hang up and not operate properly at like 50k. Once replaced, no more problems.

Do you ride your clutch, that is normal wear for riding your clutch.

 

[steved]

Its also a sign of a warped pressure plate...

 

[RVTRKN]

Its also a sign of a warped pressure plate...

But wouldn't that be uneven wear on the fingers?

 

[Kohl]

I put the truck into a transmission shop. They trouble shot all possible options before opening the transmission. He started checking availability of parts to rebuild and found the compression ring of the synchronizes was back ordered. The plant burned down and a new production is expected around Sep or later.
So I took it to a deal that had 2012 3500 dually with 4:10 so I traded up.

 

[Prairie Dog]

So the "repair" only cost like $50K?

 

[AABEN]

Do you drive with your hand on the shifter. If so this is a no no

 

[Prairie Dog]

Do you drive with your hand on the shifter. If so this is a no no

Been doing that for most of 78K miles. What happens?

 

[CKESSEL]

I don't ride the clutch or rest my foot on the pedal. When at a stop, I'll put it in neutral and let the clutch out. I've changed enough clutches to know better. When I talked to the trans tech at the dealer I used to work at, the first thing he said was the the pp was the problem. I had it changed and sure enough, the fingers had flat spots on them. I am running the ZOOM ZVT in it since then and no more issues for 70k+ miles.

 

[S.Morris]

Been doing that for most of 78K miles. What happens?

It wears the shift forks on the loaded side(side pressure applied by shift lever having weight on it). It will eventually cause the stick to jump out of gear as the fork will no longer push the sliding clutch into the gear far enough.