Help Diagnosing 2000 Silverado

whitty5 · February 16, 2017

Hey Y'all,

I've been lurking here for a while, but finally had a good reason to post.

So I have a 2000 Silverado 2wd with the 4.3 automatic and 190,000 miles on the original motor and transmission.

A couple of days ago I was driving home sitting at a stoplight. I came out of the stoplight and felt a loss of power from the motor and a little bit of jerking. It finally pushed through and I got up to speed.

After about a mile, all of a sudden it slips out of gear like I shifted into neutral. I thought I had hit the column, but I hadn't. I tried to manually shift into gears with no luck.

I pulled to the side of the road and put it into park. I tried a couple of times to get the truck to go into gear but it never would. So I turned the truck off and began to call a buddy of mine for some help.

After a couple of mins I fired the truck back up and tried again to put it into gear. It went into gear and I was able to drive. Luckily I was close to my house and was able to make it home.

Now the truck will drive normally for about 1/4 mile then I will lose all gears. But if I turn the truck off and let it sit for a couple of mins I'll be able to get it into gear, but only for another 1/4 mile of so.

Now onto the sounds that it is making. When I turn the truck on and leave it in park the motor runs smooth with no sounds at first. After a couple of mins of idle a slow clunking sound starts to come on. I'm having trouble describing this sound so if a video would be helpful I can try to get one uploaded.

I got under the truck to try to pin point the sound. It's coming from right at the bellhousing of the transmission. This sound directly relates to when I lose all gears even if I never put it into gear. This sound gets worse when put into 2 and N, but will all but go away when I put into R.

I have checked the fluid level and that seems good, the color is a little brown red but no burnt smell and no signs of metal shards.

Does anybody have any thoughts as to what this problem could be?

Any suggestions would be greatly appreciated.

TLDR: Truck loses all gears shortly after startup. All gears will come back after turning the motor off and back on. Clunking noise coming from front of transmission around the bellhousing. Noise will go away when put into R. Noise gets worse when put into N and D. Noise isn't always present, but is related to when I lose gear.

Thanks for y'alls help!