today i drove home and my service engine light came on, everything was fine though i turn it off to go in my house go back out to start it up and the engine was moving very rough side to side and the rpmwent crazy going up and going down then the battery dropped all the way to dead and i heard a whistle noise think it was the alternator i turn the key to off and it still wont stop about a few min later it died something was smoking under the engine and my battery is at 10 volts

did my alternator just die?

when i bought it i noticed a new battery its a autolite now that i look at the alternator it says remanufactured ac delco. the truck got 110,000 miles on it exactly today, is this normal to go through 2 alternators on these trucks? or is there something else that can be the problem thats causing this

edit, its a 95 blazer

 

Sounds like a vacuum leak , maybe a burned vacuum hose ?

Zed

 

alright i took it out charged the battery replaced it now it works

 

You should get a battery light if it were your alternator. The engine/tranny and so much more is controlled electronically. These truck run like absolute crap if the battery gets real low (i drove my last blazer with a failed alternator for like an hour and it drained the battery so low that the truck literally wouldn't drive anymore).

 

Do you mean that you turned the ignition off and it kept running? Or the noise woldn't stop after you turned the key off??