I have a '90 5.0 convertible that has an automatic transmission and a little over 120,000 miles.
I am trying to diagnose a noise that is some where between a fan roar and a loud hum. I can drown it out with the radio, so it isn't extremely loud, but is very noticable.
The noise is absent revving the engine or slowly increasing rpm to 3500 rpm, while in park, at the curb.
The noise begins reliably at about 30 mph and builds to a slightly higher frequency as speed builds. Not a whine really, not that high pitched. It diminishes a bit above 65 mph.
I have the impression that it is in the front of the car. My initial suspicion was the fan. I had replaced the water pump, installed a thicker radiator, and now the fan is inside the shroud a good bit. The fan has had the edges trimmed to make them all even, since some had been cut on the shroud before I bought the car. A rough attempt at balancing the fan, if you will. But since it is speed related and not rpm related, it seems I should rule that out. Same for the smog pump. It is original, but that would be rpm related, were it the problem.
Also, the car has a Maximum Motorsports lowering and handling kit installed, the sport box. The kit had been on the car a while before this noise started.
Next guess.... wheel bearings?
I am trying to diagnose a noise that is some where between a fan roar and a loud hum. I can drown it out with the radio, so it isn't extremely loud, but is very noticable.
The noise is absent revving the engine or slowly increasing rpm to 3500 rpm, while in park, at the curb.
The noise begins reliably at about 30 mph and builds to a slightly higher frequency as speed builds. Not a whine really, not that high pitched. It diminishes a bit above 65 mph.
I have the impression that it is in the front of the car. My initial suspicion was the fan. I had replaced the water pump, installed a thicker radiator, and now the fan is inside the shroud a good bit. The fan has had the edges trimmed to make them all even, since some had been cut on the shroud before I bought the car. A rough attempt at balancing the fan, if you will. But since it is speed related and not rpm related, it seems I should rule that out. Same for the smog pump. It is original, but that would be rpm related, were it the problem.
Also, the car has a Maximum Motorsports lowering and handling kit installed, the sport box. The kit had been on the car a while before this noise started.
Next guess.... wheel bearings?