Engine/Transmission (1994 - 1998) NV4500 4th gear question

[Proram]

Need a little input here guy's, i have a 97 3500 2wd with a 5spd, 197,000 miles. bought the truck a couple months ago outa texas, truck was Horriblely neglected but a VERY good price, Here's the question, it grinds going into 4th. (4th only) motor and trans are outa truck as of now for a good cleaning and reseal, have top and input off trans, Fluid looks Perfect, as do 4th gear syncro's and hub. (syncro teeth are nice and crisp , no rounding at all) as is hub and gears, not even a filing in the bottom of trans. clutch was wasted, input was sloppy, would an excessivly sloppy input bearing cause the 4th gear grind? (had to double clutch it for smooth shifts) being the 4th gear is closest to the input shaft/bearing. Trans was smooth as glass cept' for the 4th gear. also the input shaft bearing seems to be in good shape too.

i think i've given all the info i can for some good input. Thanks for any thoughts.



Scott@RDP

 

[SRadke]

Sounds like you've got a problem with the 4th gear syncro. Possible some of the friction material from the inside of it has been damaged. If it was grinding that bad I'd pull the shaft out and replace the syncro. It's only a long hour of work from where you are now. My $. 02



-Scott

 

[NBowlin]

Synchros have a clutch like material(lack of a better term) on the inside of them? it wears out. I could be wrong, but when I replaced my third and it was pretty much worn away. You may have looked at this, or it may not matter. Just thinking.

 

[GAmes]

When my input shaft bearing went out there was no noise or grinding at all in shifting gears. However, once in 1,2,3 or 5 there was plenty of noise when the clutch was engaged. With 197k and the trans out of the truck now might be a good time for a total refresh and a fully spined 5th gear fix if it hasn't been done.