2006 Grand Prix clunking in front end

[vibeguy]

my 2006 grand prix has multiple clunking when starting or stopping coming from the front end, both sides on occasions it seems. 2 shops couldn't find the source. GM dealer wants to start ripping apart the engine. Any ideas? Was thinking of replacing lower control arm bushings. Thanks for any info!

[BNaylor]

Welcome to AF.

What's the mileage on your GP?

[vibeguy]

It has about 40,000 mi. Thanks for responding.

[BNaylor]

Thats low mileage to get noises from either the suspension system or drivetrain or engine for that matter. Can you better describe the sounds you are getting or conditions? Was this purchased new or used?

[vibeguy]

It was purchased used with 14,000 miles. Maybe a rental? Was originally titled in CA. Anyway, at first it was the occasional single clunk when starting out. It's progressively gotten worse with multiple clunks nearly everytime accelerating and stopping. Doesn't really seem to be steering related, just starting and stopping. Time line from first heard till now is under a year but more than a couple months.

[3100]

Originally Posted by vibeguy

It was purchased used with 14,000 miles. Maybe a rental? Was originally titled in CA. Anyway, at first it was the occasional single clunk when starting out. It's progressively gotten worse with multiple clunks nearly everytime accelerating and stopping. Doesn't really seem to be steering related, just starting and stopping. Time line from first heard till now is under a year but more than a couple months.

sounds like the dog bone, or to use professional term "torque strut/mount"

[rkvons]

Couldn't it also be a broken front stabilizer link?

[vibeguy]

Thanks for the info guys. It's the wife's car and she's getting antsy and has her mind made up on bringing it in. I'm going to tell them to change the lower control arm bushings and check into the sway bar links. Seems common problem on GM's? I checked the dogbones and they seem alright. Held the brake and hit the gas. No noises, seem to be ok. I'll post an update after.

[3100]

Originally Posted by vibeguy

Thanks for the info guys. It's the wife's car and she's getting antsy and has her mind made up on bringing it in. I'm going to tell them to change the lower control arm bushings and check into the sway bar links. Seems common problem on GM's? I checked the dogbones and they seem alright. Held the brake and hit the gas. No noises, seem to be ok. I'll post an update after.

There is only one dog bone, don't confuse it with engine mounts on top. This one is on the bottom and on front passenger side. Control arm bushings you can check when front side is lifted in the air. The rubber part of the bushings should be in place. If the rubber part is hanging then it is bad.

[BNaylor]

Originally Posted by 3100

There is only one dog bone, don't confuse it with engine mounts on top.

It depends on the engine on how many dog bone engine mounts. The L32 (Supercharged) and L26 (NA) SIII 3800 engines have two. GXP with with LS4 5.3L V8 has one on left, top, front side of engine only.

To the OP what engine or model Grand Prix do you have?


Nonetheless, too bad the OP only has the 3 yr/36,000 mile GM factory warranty since this is a 2006. For 2007 and up it is 5 yrs/100,000 miles. An issue like the OP has could be covered sparing expense.

[vibeguy]

Took the car to the dealer as stated. They found it. Couldn't believe what it was. The brace above the Battery on the P.S. that goes on an angle was loose. Must have not been retightened enough after the battery was replaced last winter. They tightened it down, no more clunk. Second time I brought it in, figured it out after an hour this time. Didn't charge me anything. Can't complaign about that. Thanks for all the info though. Appreciate it.