Attention: TDR Forum Junkies ok... little long but here is the story.
VP44 died in september. replaced it with a newer "revised" version of the stock pump. ran it about 200 miles easy (no hauling or towing) seems that everything is fine. at that time i also put a MBRP 4" exhaust with no muffler on it as well. after that it went to the paint shop for over 3 weeks and then due to my work schedule didn't get finished and run until last week. (about 3 months total).
so now for my issue... i was towing last week about 7500lbs. and as i was accelerating on interstate ramps in 3rd and 4th and then up hills on the interstate in 5th gear i could hear a new and different sound that sounds like a cross between geartrain noise and a hissing sound that appears to come from the front left of the engine. boost was holding steady at 22psi EGT's were under 1200* pre-turbo. the turbo was whining normally and no loss of performance is noted. check oil and fluids, everything is good. my concern initially was air oscillation or pulsation (i think) that will destroy a turbo quickly, but then my other though was maybe the new VP44 being a little noisy. it only seems to happen under heavy acceleration and under heavy load... any thoughts or ideas???
VP44 died in september. replaced it with a newer "revised" version of the stock pump. ran it about 200 miles easy (no hauling or towing) seems that everything is fine. at that time i also put a MBRP 4" exhaust with no muffler on it as well. after that it went to the paint shop for over 3 weeks and then due to my work schedule didn't get finished and run until last week. (about 3 months total).
so now for my issue... i was towing last week about 7500lbs. and as i was accelerating on interstate ramps in 3rd and 4th and then up hills on the interstate in 5th gear i could hear a new and different sound that sounds like a cross between geartrain noise and a hissing sound that appears to come from the front left of the engine. boost was holding steady at 22psi EGT's were under 1200* pre-turbo. the turbo was whining normally and no loss of performance is noted. check oil and fluids, everything is good. my concern initially was air oscillation or pulsation (i think) that will destroy a turbo quickly, but then my other though was maybe the new VP44 being a little noisy. it only seems to happen under heavy acceleration and under heavy load... any thoughts or ideas???
