Pontiac Tech Tip: Grinding and/or Growling Noise in Park on Incline

Pontiac Tech Tip: Grinding and/or Growling Noise in Park on Incline

Owners of some vehicles equipped with Hydra-Matic front wheel drive transaxles may comment on a grinding and/or growling noise that is noticeable when standing in PARK on a hill or slope with the engine running and the parking brake not applied.

Affected Models:
2007 and prior Pontiac passenger cars and light trucks with Hydra-Matic front wheel drive (FWD) automatic transmissions.

Service Information:
Owners of some vehicles equipped with Hydra-Matic front wheel drive transaxles may comment on a grinding and/or growling noise that is noticeable when standing in PARK on a hill or slope with the engine running and the parking brake not applied. Under these conditions, the weight of the vehicle puts a load on the parking pawl which can create a “ground-out” path through the drive axles, front struts, springs and spring towers. Normal engine noise can be transmitted to the passenger compartment through the “ground-out” path.

Owners concerned about this condition should be advised to apply the parking brake prior to shifting into PARK. This is the recommended procedure described in the owner’s manual. Applying the parking brake first will put the load of the vehicle on the rear brakes rather than on the parking pawl.

Refer the owner to the appropriate owner’s manual for additional details and instructions.

Courtesy of Mitchell 1.

For more information on Mitchell 1 products and services, automotive professionals can log onto the company’s website at www.mitchell1.com.

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