Damfare

Hello this is my first time here. I am looking for help diagnosing my 2000 chevy stepside with a 4.8 liter and nv3500 manual transmission. My nv3500 is acting up. 1ts issue is with engine running I have a noticeable noise like a bearing going when I press the clutch and hold it down it goes away when I release the clutch it's back. I believe this to be the input bearing ? 2nd issue only happens when shifting from first to second. when the transmission is warm and I press the clutch down, shift into second and on the release of the clutch it clunks when engaging into second. This does not happen on the down shift and only when going into second. Any help would be really appreciated. J am planning on fixing myself but better diagnosis would be much needed. Thanks damon

adamnC

you are correct in the first issue. As far as the second, try shifting without clutch. Find the sweet spot on deceleration. If no clunk then check for excessive driveline slack. 4wd tend to have more slack than 2wd. If shifting without clutching is impossible, synchos will need replacement

hanky

Your best bet is to remove and carefully disassemble the trans. There are at least 4 bearings to be concerned with. Since 1st and 2nd gear are at the rear of the trans , you will need to go the full disassemble route.You could have a broken bronze synchro ring and the noise may be coming from the back end also.Make sure you have enough room to lay out the parts so you can get them back together correctly.. Once you see the entire parts condition you can get what you need and after cleaning the parts well reassemble everything. Just take your time and go slow so you don't miss anything. A manual can be quite helpful if you have never done this before..
It is not difficult, you just have to be careful not to overlook anything..