Hi,

I have a 2000 S10 Blazer 4.3 Automatic 180K miles. Looking for a little insight on what could be causing a whining noise. The whining is only heard when coasting (no pressure on gas pedal) 30-70mph. The first bit of gas applied whining goes away. Also noticed when coasting and slight turn on a right curve whining also stops. Not left turn just a right turn/curve. Shifters great and no slipping or sluggishness. Not sure if I'm looking at wheel bearings, something with transmission, a pinion gear or some other issue in drive line. Also feels like there is a bit more force then normal put back on transmission when driving and I let of gas. Any help or "check this" ideas would be great.

Thanks

 

I have a 1999 that whines but my problem is the serpentine belt ! maybe you have a bad belt, the idler pulley or clutch fan making a noise !

 

Belts are good and belt tensioner was replaced this summer. It's only whining during decelerating. I'm afraid after researching everything points to bad or going bad pinion bearings. I'm going to get a second opinion on that before tackling that project.

 

My '99 Blazer made a strange grinding/ whining noise as well. It would happen at random- while coasting, while on the gas, while on the brake... Does putting it in 4wd make it stop? If so, you may need to replace the vacuum actuator switch on your transfer case. It was a $20 part and an easy fix.

 

My 2000 blazer ls has done the same thing for 40k miles. I think I have found the problem in the rear differential. The carriage bearing and a spider gear is shot. Bought new bearings and spider gears and found the carriage needs additional shims, 0.045” play right and left on the carriage. Bought a shim pack today at advanced auto for $5.99.
Waiting for garage to warm up before install of shims. Will post if it fixes it.