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Car Clunk

I was on my way into work this a.m. and was at the end of my trip (a 30 mile drive). While there was a lot of taffic congestion, we moved at about 20 mph. When I accelerated, I felt a “clunking” sensation. It happened a few times more when I moved from a idling position. I didn’t have enough open space to see if it continued through all gears as I arrived at my destination. My car is a 2002 Chevy Impala with 149,000 highway miles and is well-maintained. What could it be? Transmission, U-joint? Please advise.



Thanks!

If I were you, the first thing I would do is to check the level, the color, and the smell of the transmission fluid. This car does not have u-joints, so you can rule that out. It does have CV joints on the front drive axles, but worn CV joints don’t make a clunking noise when driving straight ahead–at least not in my experience.

Thanks for the response! I have noticed a burning smell from the engine lately that permeates through my vents when I use outside air. I guess I should retrack my comment about the car being “well-maintained” and get it to my mechanic pronto!

Lizzy, Is It Just One Clunk Per Acceleration?

VDC Driver has given you good advice. Have the mechanic take a look at engine mounts, too. I have seen Impalas with broken front mounts. The smell could be related or an unrelated problem, possibly minor, caught early.

Yes, just one clunk per acceleration. However, I do recall that on a long trip back in early January with a fully loaded car, I noticed the clunking through all gears…that probably was my first warning.

If you’re familiar with Impalas, I’ve had trouble with my Traction Control and had it in to the dealer last year. They couldn’t find anything wrong except some issues with my power steering. They replaced the belt and added fluid. It was fine for a while and started acting up in the fall. Since then, I’ve been driving with the traction off. There’s a grinding noise when I make sharp turns and my message center says “traction active.” I would appreciate any thoughts? Thanks!

I’d Still Have Everything Checked Out.

That traction control problem and the grinding turns can be related. Your Impala might have a worn wheel bearing or bearing/hub that needs replacement. Extra movement in this area could cause a grind and also cause the wheel sensor to activate the traction control light. I wouldn’t wait too long to have this checked. Grinding noises are often Mother Nature’s way of making you aware of a problem that can get worse with use or become dangerous. Have you had any ABS (Anti-Lock Brakes)warning? This would relate, also.

I hope this Impala has been good to you. You didn’t say if you are the original owner or how long you’ve had it. Hopefully you haven’t spent too much on maintenance and repairs. You might have to spend a little to get it back in shape.
Find out which items require immediate attention and take care of them now.

By the way, do you have a 3.4L or 3.8L engine? I think the 3.8Ls say 3800 right smack in the middle of the cover on top of the engine.

Let us know what you find out.

Yes, the anti-lock brake message came up one time after the grinding. And thankfully not since then. I forgot to mention that right before I had the dealer check it out, I had the Traction Control in the off position and I still had grinding. That has not happened since, but I guess I’m pushing my luck…

I am the original owner/driver and it is a 3.8L. This car has had hardly any maintenance/repair issues until recently and with the car at its 150,000 mile mark, it’s probably time for an overhaul/makeover. I am happy to report that it gets 28 mpg highway which isn’t too bad for a car this size. I also plan on keeping it as long as possible and will take action to get her back in shape. Thanks for your comments and recommendations!

That Is A Great Engine. The MPG Can Be 27-31. I Like These Impalas.

You’re welcome. Good Luck, Lizzy!