Skip the auto shop - Our mechanics make house calls

Q: 2004 Chevy Express makes noise while idling

asked by on

2004 Chevy Express 1500 402,000 miles. It makes a moaning sound when idling and gets louder the higher the RPM is. Transmission shifts kind of hard. What do you recommend?

The first thing you’d want to check is the power steering. A lot of times, they groan on those. If it’s not the power steering, a lot of times it would be the transmission. If it’s coming from the transmission, you’d want to pin-point where the noise is coming from inside there.

If you don’t have the equipment, call on a professional technician, such as one from YourMechanic. Depending on the situation they may put various mics on parts of the car and put on headphones on to listen to it with a receiver to see where the noises are coming from. If it isn’t the transmission, it’s probably going to need a rebuild. But you could try adding one quart of Lucas transmission fluid. That can sometimes help for a while. However, you’ll want to have the noise diagnosed if you want to find a long-term repair and prevent any further troubles.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Gauges not working

This is a common issue. The instrument cluster in your Hummer uses stepper motors to move the needles. Sometimes the stepper motors fail and wont work at all, and other times they give a crazy reading like needle in the...

Q: Issues with EVAP system

It is very possible you may have a vacuum leak causing a rough idle and too much air on acceleration causing sputtering and rough running issues. A smoke check of the induction system would be a good idea. Reading the...

Q: Brand new motor will not start

Hi there. From the description you have provided, changing the vehicle engine, shorting the alternator and now a no start, is going to require proper diagnoses. The computer recognizing a fault in the auto shutdown relay circuit, is encouraging, the...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.