nv4500 grinding in every gear

[v-jeffl]

I have an 87 suburban and just finished installing a junkyard sourced nv4500 using an AA bellhousingh and hydraulic slave bracket. The junkyard said it was a great trans and had taken it out of a truck that they had been driving around the yard. When sitting still with the clutch pedal depressed it slides into every gear smoothly but when moving it grinds in every gear every time. It doesn't matter if I shift fast, slow or at high or low rpm it grinds. I checked clutch disengagement and it seems ok, Im getting about 3/4 of an inch movment from the slave cylinder but I dont know if thats a normal amount. The clutch engagement seems fine. Im using properly bled factory spec hydraulics. I fear a worn out trans but before I pull it back out I wanted some feed back. Any help would be appreciated.

 

[bucket]

A sticking pilot bushing comes to mind. But I assume that's new?

 

[86Peter454]

sounds like a synchro issue.

actually. those transmissions where VERY picky about what fluid you use.

i suggest getting actual GM ********* they want you to use. i have heard decent things about the royal purple (thats what i was going to run in mine before its fully took a dump on me)

what fluid are you currently running?

 

[bucket]

Oh yeah, they take GM's Syncromesh. I'm really curious what fluid is in it now.

 

[v-jeffl]

I put in a new pilot bushing. Im using the trans fluild that dodge uses in there nv4500 trans I asume it is the same $30.00 a quart. However when I drained the old stuff out it was thick like gear oil and smelled like gear oil and the nv4500 oil was clear and much thinner. There's a good possibility the wrong oil was in it before and fried the syncros. I dont have any experience in manual trans but have rebuilt a couple of np208s . I might give it a try, can anybody recommend a good rebuild manual preferably with good pictures.