Best Guess on a NV4500 Problem

[1stgen4evr]

My Brother has a 2000 with a NV transmission. It has gotten hard to shift (all gears). Any thoughts or previous experience from the membership. It isn't noisy. Sometimes it works perfectly. I can drive it even though it is hard to shift up or down sometimes. The other drivers have a bit more trouble.



No metal in the sump. Bright clean gears. Syncros have plenty material. Using the liquid gold transmission fluid. Synthrol I think it is called.



Pilot brg maybe?



Shift assembly?



Shift Interlock balls?



Preload?



Remember I'm a Getrag man myself and have not built one of these. (and ain't fixing to)



James

 

[McCRam]

On my last transmission. I put in some mopar limited slip additive into the new oil. After 500 miles or so, it started to shift easier again. I did all that to try to get the transmission to last a little longer. It was making a lot of gear noise, and I was having a heck of a time getting it into reverse. Fifth gear went out again and I am in the middle of putting a new 4500 in, but the additive helped for about 3000 miles, and it kept shifting better.

 

[Philip]

Sometimes it works perfectly.

I would look around the hyd clutch. The slave cyl might be sticking or the master cylinder going bad or both.

 

[BJMarshall]

James,

Thy're not any harder to work on that the 360's. With the shifting being hard, I would suspect pilot bearing first or clutch hydraulics as Philip said. It is odd that it doesn't do it all the time though. That would also make me lean more toward the hydraulic clutch than pilot, but the stock type pilot will not last near as long as the clutch in most cases.

I've got my 4500 apart on the table right now, and it looked perfect from what Icould see through the PTO covers as well, but when I got it apart I found all kinds of problems. None were major taken by themselves, but all of them together were fixing to cause major problems.

Also remember the clearance on the mainshaft and countershaft are only supposed to be . 002 to . 006 so just about any discernable movement is loose.

Barry

 

[1stgen4evr]

James,

They're not any harder to work on than the 360's.



Let me be a bit more honest Barry. At least more than the guy that sold me one claiming it to be 'good'. It was a run low with ruined input shaft and companion gear on the cluster. It did however introduce me to the certifiable Rube Goldberg fifth gear engineering. I didn't reassemble it and have sold all but the mainshaft with gears and shift cap (old style). I didn't lose money on it.



Since I have two spare Getrags, and since I don't do transmission repair for any one but local swapping buddies, I don't expect to be repairing a 4500. Clearly they work well as can be determined by the number of members that have made the change.



From the comments I am leaning toward the clutch, either the slave/disengagment malfunctioning or the pilot brg causing a problem. The guys at the shop had this transmission out and back in without any input from me. Only after reinstalling the unit and then experiencing somewhat the same problem, I was asked for an opinion. I did see the transmission (open) on the bench and it was very clean without damage to anything I saw in casual observation. The problem that was being addressed related to the fith gear shifting/hanging in gear. Even when it hangs up, it can be shifted with a bar through the shift lever hole. A few new parts were installed in the fifth gear workings. I really don't think that a new/different transmission will help.



Unless it is just pulled and a reman installed, I will reply later when the solution is reached.



Thanks

James