NV5600 Grinding In 3rd And 4th Gears
 

Hey guys, lately ive noticed, mainly when i first start driving my truck after sitting for a few hours or more, my truck will grind going into 3rd gear, its not a bad grind but its a grind none the less. Also, just recently it started doing it in 4th gear as well. Im not sure if this would be signs of my already hurt clutch going out on me or if this is something else. Please give me your input.

hmmm just a guess but synchros maybe. only does it when cold? when was the last fluid change?

does it do it when you double clutch it? if it dosen't then i'd bet on the syncro's.....

it only does it when cold or if i shift it fast, today after work i shifted it a little slower than normal and it never once did it

Not at all sure on fluid change, has 110k on it, ive owned it for 14k of that and ive never touched the fluid.

Maybe thats an idea for the WI GTG in 2 wks???

Also i can show you guys what its doing that day too if it does it

Sounds like synchros to me, all shifting it slower is doing is letting the engine rpm match the transmission. That's the way big trucks r driven, because most of us never touch the clutch again after we get movin.

ok so my next question is, does anyone sell just the synchros for the NV5600 and is it a serviceable transmission or not

Chances are if the clutch is hurt and it not aftermarket like southbend with the up graded pilot bearing.Then I am going to say that your pilot bearing is not happy this can cause drag on the input shaft and cause the gears to grind.Or it is totaly destroyed and the added stress of the missing bearing is causing your input shaft to wear on the main shaft snout wich is right where 3rd and 4th gear synchros are at. My suggestion is to drain the fluid into a clean pan and look for any damage such as metal flakes.If no damage add new fluid make shure it is synchromesh and test drive. If the fluid change does nothing than I would take it to a compitant trans shop and have it completely gone through. You will have to take it completely apart for just synchros so why not do the whole thing while your there. Hope some of my babbling helped

same problem with my nv 4500
 

I have the same problem with my 97 2500 with the nv 4500 and I have changed the fluid with no improvement so I would be interested to see what you find on your truck.

ok

what does it generally cost to have the whole tranny gone through and fix any damaged parts.

The NV-5600 is NOT meant to shift fast. Shifts should always be slow and delibarate.