My husbands work truck is a 2001 s10 4 by 4. It just started making a sloshing sound behind the dash when it first starts going. Then when he gets to about 55 and lets off the gas it starts making a VERY loud whining sound that gets louder as it slows down. The sound stops when the car does or when he pressed the accelerator again. Any ideas before we go to the shop Monday?