I own a 1997 Chevy 1500/Silverado/Z71, 3rd door, 4 X 4, 5.7 L., 104,500 miles - I love this truck. It runs and rides very well. I noticed on the interstate that if you punch it down around 40 - 60 mph (wide open) the truck takes off like normal and sounds really good. But when you get up to around 3500 - 4000 rpm and 70 mph you suddenly here and feel like you're going over rumble strips. But louder and you can feel it in then seat (vibrations.) The sound, when you're sitting in the driver's seat, sounds like it is coming from the trans hump, in the front and up through the dash. Oil pressure, coolant temp. and voltage all stay in the normal positions. You cannot feel it in the steering wheel or gas pedal. The "Service Engine Light" does not come on. You can just hear it and feel it in your butt (through the seat.) If you back off the throttle, it stops immediately. But does it again 7 out of 10 times you put it through the motions that I described. If you keep the throttle mashed the noise will stop after about 6 - 7 seconds but I can't say that it stops when it shifts. Any advice or tips that anyone of you good people could provide would be appreciated. Doc, if you're reading this I would appreciate your opinion. Thanks
- posted
19 years ago