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1990 k1500 new tranny or throwout?

So about a month ago, I noticed a small whining coming from under the gear selector, but up a little bit. It only started very quiet, barely loud enough to hear over the already loud old engine, that is straight piped and now dumps right under the passenger door. The whining came from what sounded like the bell housing but it only happened when the truck was starting into motion so I never stuck myself under it to find out exactly where the noise was coming from for safety reasons. The whining started to get louder and started to move closer to right under the gear selector, still only when the clutch is just hitting the friction point. The noise stopped getting louder and some days it wouldn’t even make the sound (it’s a very moody truck). I ignored it. I figured that first gear was just giving out on me and I don’t have enough money to buy a whole new rebuilt tranny. Now the sound has moved to the clutch pedal itself, just under the floorboard. When in gear, and the clutch is fully depressed, when it hits the bottom of the speed range of said gear, a very very loud KRRRRRRRRRRR can be heard from just under the gear selector. It sounds like the throwout is keeping it in gear just enough that gears are slamming into each other. Is it something else or is it the bearing?? Anything would help. Thank you.

To help with some possible confusion. The sound was constant until it moved to under the clutch pedal. That’s when it became intermittent.

The whine only comes when at friction point. The KRRR sound is well after the clutch is engaged, then disengaged (pedal up to floorboard).

A faulty throw-out bearing tends to make noises whenever the clutch pedal is depressed, more or less independent of what gear the transmission is in. There’s a bearing where the transmission input shaft connects up w/the flywheel, right in the center of the flywheel. If not the throwout bearing, could be that. There’s so many moving parts in the transmission proper, hard to say about that. You’ve check the gear oil level, right? There’s a weird problem sometimes, the crankshaft end-play is too much. When you press on the clutch it pushes on the flywheel and the flywheel is connected to the crankshaft, so pressing on the clutch tends to push the crankshaft towards the front of the engine. there’s gadgets there to prevent it from moving too far, but sometimes those wear out.

No not yet. First time I’ve heard to check the oil level. Will definitely have to. I thought the pilot bearing as well, but it never struggles to get into gear, and it doesn’t struggle to stay in gear, so that’s why I was pointing towards throwout.

I’d guess throw-out bearing at this point too.

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