Mechanics

VIBRATION/NOISE AT 30-40 MPH

2008 Chrysler PT Cruiser

Noises problem
2008 Chrysler PT Cruiser 4 cyl Two Wheel Drive Automatic 42000 miles

When car is running between 30 and 40 mph, there is what sounds like engine braking noise and vibration can be felt through the gas pedal. What could be causing this?
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SteveThroop
May 14, 2010.



Sorry for the delay in answering your question. What is an engin braking noise? Is it a deep rumble or a scraping sounds? Does it only do it in a particular gear? If you downshift and manually hold a low gear in higher rpms will it still make the noise at that speed?

Tiny
Jack42
May 24, 2010.
The vibration seems to be just related to speed. I have since put the car in neutral while driving at 30-40 mph, and the vibration and noise doesn't change at all. The noise is more of a low to midrange rumble.

Tiny
SteveThroop
May 24, 2010.
Have you tried rotating the tires front to back to see if the vibration changes. Does the steering wheel move back and forth when it is vibrating?

Tiny
Jack42
May 24, 2010.
I haven't tried rotating the tires. There isn't any vibration or movement in the steering wheel, just feel it in the gas pedal.

Tiny
SteveThroop
May 24, 2010.
If it is tire related the noise/vibration will change.A front end vibration wont always make the wheel shake, was just looking to narrow it down. Have you tried manually holding a gear to see if it is related to the trans?

Tiny
Jack42
May 25, 2010.
The car's an automatic, so I can't hold a gear, but when I shift into neutral when going between 30 and 40 mph the low to midrange rumble and the vibration through the gas pedal don't change.

Tiny
SteveThroop
May 25, 2010.
Start by rotating tires to see if it changes anything, also inspect the tires to see if the tread is seperating (bulges in tread), this can cause what you describe. If you put the trans selector in 2 instead of D or OD it will stay in 2nd gear. While rotating tires, check the front hub bearings as well.

Tiny
Jack42
May 26, 2010.