NV4500 hard to shift

[RDMueller]

Over the past few months I’ve started to have problems shifting, but the problem is not consistent. Sometimes no problem at all, other times it can be almost impossible to get it into gear. It happens both when at a standstill shifting into 1st, 2nd or R, but also while moving and up shifting / down shifting.

Based on what I’ve read online the first thing to consider would be the clutch not fully disengaging, so I may just start by replacing the clutch master and slave since it’s easy and fairly inexpensive. Before I do that though, just thought I’d check here to see if there’s anything else I should look at or consider.

Btw, the truck is a 2001.5, 2WD, basically stock with 90k on the transmission and 130k on the clutch. Thanks in advance for any tips or advice!

 

[GCroyle]

RDMueller,

Hydro's, does the pedal feel loose when you just start to push it like it has freeplay at the top or does it start to create PSI immediately as you push on pedal? Freeplay not good, immediate PSI good sign hydro's are OK. More details are available.

At mileage the two things that are now bigger suspects are possible pilot bearing drag turning input shaft but the overlooked at clutch R&R is a through cleanup of the splines and a light film of grease on splines to prevent rust. If the disc cannot slide, your disc is still driving the mainshaft, shifting is difficult. These two are more from the some times it does sometimes it doesn't category.

Go feel the pedal like a safe cracker checking out a safe tumbler.

Gary

 

[RDMueller]

Thank you Gary, checked and found almost no pressure in the first 1/3 of pedal travel. In fact, I was able to get that 1st third of travel with my little finger, guessing force needed would be measured in ounces not pounds. After that, the amount of force needed for further movement builds very rapidly. I guess this indicates that even if there are other issues, replacing the master/slave is needed anyway.

 

[RDMueller]

I’ll update after that.

 

[GCroyle]

Check fluid level, roughly middle of reservoir is typical. Fluid level low? OK now look for any wet spots on master, master cyl where the push rod goes into master, weeping? Next inspect line and outside of slave cyl. None found?
Now remove slave cyl from bell housing. Carefully remove push rod and dust boot. Do not push clutch pedal with cyl removed. Fluid behind boot? shouldn't be any.

No leaks allowed.

Good luck.

 

[RDMueller]

Went ahead and replaced both the master and slave with a pre-filled kit. The job was easy and took no more than an hour. The difference is night and day! The shifts are smooth as silk now, hasn’t been this good in tens of thousands of miles, wish I had done it a lot sooner.

 

[GCroyle]

Good news.

The pile of clutches replaced due to air in hydro's is massive. Basic observations and testing beats pulling a trans.