Whining w/acceleration and deceleration in 1st and 2nd gear

chevrolet
malibumaxx

#1

I have a 2006 Chevy Malibu Max with automatic transmission, 129,000 miles. It’s got a higher pitched whine that increases as I accelerate between first and second gear and between 2nd and 3rd. I can’t hear once it’s in 3rd gear. It sounds like an RC car or early video game race car sound. I can hear it winding down as I slow down through those gears. It’s also audible when the car is in neutral or park, but not then the brakes are fully applied. I can’t really hear it in reverse.

I bought it used with 65,000 miles on it. I’m not sure what was done before that as far as maintenance/preventative maint. I did get a transmission flush three years ago (sorry, don’t know the mileage at that time). I don’t think this will impact things in any way, but I just changed the spark plugs and wires a few weeks ago.

It has a rough/shuddery idle (but doesn’t feel like it’s goign to stall out) and seems to be riding rougher than usual lately. I feel it more in the seat/overall car vibrations than through the steering wheel.

Any ideas? Transmission Oil Pump? Planetary Gear Set? I was really hoping to not have an expensive repair, but I am fearing the worst.


#2

Sounds like a transmission or differential problem. First step – presuming you don’t want to start with a transmission shop diagnosis – is to do a proper service on the transmission. If your transmission is so configured, drop the pan, replace the filter, new fluid. If that helps but doesn’t solve it, wait a week and do it again. If the differential is serviced separately, do a proper service on that too.

If you decide to just take it to a shop, you could do a couple of tests first, that will save some time. For example get it to the point this is happening, then shift into neutral and coast. How does that effect the sound? Next get it in the next higher gear, going faster than when you hear the problem, then let your foot off the accelerator and coast (while in gear) back through that problem speed. Note how the sound changes. Do the same thing, but coast in neutral back down through that problematic speed range.


#3

Are you sure the whine is coming from the transmission? The most common item to whine is the power steering pump.