car idles bad when brake pressed

[gotspeed]

97 J30 113,000 miles. when i get ready to shift my car from idle, the cars belts start squeaking and the lights dim a little. this happens before i put the car into gear. would a bad alternator cause the belts to squeak when the brake is pressed?'

[maxnix]

Yes, but so would bad pulleys or a worn out belt.

Maintenance history, please?

[gotspeed]

i bought the car with about 35,000 miles on it and i havent changed any belts whatsoever, i have had the trans flushed, oil filter, fuel filter changes. Maf sensor replaced this year. I know the belts are due for replacement, but i am still doing my research on how to change them all out. the car does squeal something awful when starting up from a cold start. but then it goes away when i hear this blower noise kicks in after about 4 sec. but then when i get ready to back up and put my foot on the brake to put it in gear and turn on the lights the squeal starts again, not as loud but it only starts again while either the light is on or when the brakes are pressed.

[Amesdude25]

agree, bearings and/or belts. also belt tension, maybe to loose