I just had a mechanic replace my brake/hydraulic lines up front. However, there is a huge knocking noise while I drive now. The knocking goes away during braking and during acceleration. It sounds really bad and loud and the knocking/clunking gets faster the faster I go.

I've read forums and everything from the top strut mount to the stabilizer bar bushings have been mentioned to be replaced. I have setup to take my car in on Tuesday, 8/7, but i'm worried something might happen while i'm driving before then. Some say it's mainly the sway bar being loose or even engine mounts. I tried to call the dealership, but of course they want me to go in so they can look at it before telling me what it may be. Is there anyway I can check what it is before going into the shop and spending a huge amount of money? I've also read it could be motor/engine mounts, however, the mechanic did say that if would knock/clunk during idle or in park too. Any suggestions?

Thank you in advance!

Additional information.

I've had this car since Oct 2000. I've paid this car off in 2006, and never had a problem until this year, 2012, that's not the usual like blowout tires, changing rotors, etc. I've had to replace upper radiator hose, both front hydraulic/brake lines, steering column lock, and thermostat this year alone. Will have to replace the alternator soon, per the mechanic, due to it sounding like it's going out.

 

Welcome to the Forum!

Is the noise up high like behind the dash? Or is it low like under your feet? Up high is the strut mount area. Low is more difficult since there are so many things near your feet.

Does the sound happen only over bumps? Does it get louder the faster you go? Does it happen only when sitting still?

For me, worn motor mounts made the car shake noticeably when stopped, in gear, with your foot on the brake. It did not make a knocking noise even when going from Park to Drive, just started shaking the car.

You can remove the front wheels and look where the anti-sway bar curves under the body to see the anti-sway bar mounts.

For your alternator check this thread. This is my next project on my 2001 when I get home.
https://volvoforums.com/forum/volvo-...b4204t2-63472/

 

The clunking I can feel on the gas and brake pedal. Nothing in the steering wheel. It happens during regular driving. It does not make the clunking noise or feel when accelerating or braking. Just when I'm at speed. I've checked the upper strut mounts and they look good. No tears or breaks in the rubber. I've checked around the wheel well area, but cannot really get under the car since I'm at work and only checked while I was on lunch/break. The sound and clunking feel actually gets louder and faster the faster I go. No noise or clunking when I'm sitting still at all. When I accelerate to the posted speed limit, nothing until I stay steady at a speed. Breaking I dont get any clunking noise or fell either. Do you think they could have did something to the tie rods while replacing the actual brake/hydraulic lines up front?

 

I've rolled all my windows down to hear where the clunking is coming from and it seems like it's in the front driver side wheel well.

 

I believe worn tie rods would cause sloppy steering and worn out tires but not knocking.

Did this start only after the mechanic did the work? Your description sounds like a CV shaft but just replacing the brake lines should not have affected them unless someone jacked up the car improperly and bent something.

 

Yes. My car ran perfectly fine until after I got it back from the shop which was Tuesday. I drove it home, then to work on Wednesday. It worked fine. Today it started, and I didn't hit any potholes or curbs or anything. It just started on my way to work, which is a straight shot from where I live. The steering doesn't feel sloppy and my tires dont show any wear, other than normal. I got new tires about 6 months ago.

 

How much would a CV shaft cost to replace?

 

It may be coincidence but I'm highly suspicious of the mechanics work. I've replaced my driver's side brake line and it only involved removing the caliper. Can you take it back to the mechanic? Maybe he/she left something loose or missing?

The CV shaft is not a big deal to replace. It's still expensive if someone else does the work. Maybe 2 hours labor plus parts.

 

I found parts for the CV from $40-$50. How long does it take to replace it? Is it a quick swap?

 

I'm guessing 2 hours with the correct tools. I've never replaced mine though with 175K miles. As I said above, I'd take it back and have the mechanic look at it to make sure he did not leave something loose or missing.

 

Thanks. You replied right before I asked. The place I go to is owned by a really good guy. I've been going to him for years. Now some parts are expensive, but they are reasonable compared to the dealership. They did say they may have left something loose and that they would need me to bring it in to check it out. Hopefully that is the case. I'm going to check the anti-sway bar mounts when I get home, but do you have a picture that would assist me in what I'm actually looking for? I haven't really gotten back into working on my car since I'm still finishing school, while working a full time job, and raising a 2 year old.

 

I'm surprised all the issues I have is starting now. I've had this car for 12 years, put over 200k on this car, and it's now starting to go out on me. It's my very first new car that I purchased. I don't really want to part ways with it, even though my fiance and her family state it's time for a new car for me.

 

The anti-sway bar bushing is a 2 piece aluminum and rubber bushing. Look at this page:
VOLVO S40 SUSPENSION FRONT 2000-2012 at Swedish Auto Parts

Scroll down near the bottom and look at part number 30620990 and 30620989. Those make up the top and bottom. Notice the first part has one bolt hole? That is all that bolts it down. Both of mine broke next to the bolt allowing the bushing to lift and come apart. It only knocked over bumps though....

Let us know what you find.

 

So while driving home from work I noticed when I went really slow that the knocking sound and feel turned into a scrape. I tested this around my neighborhood. I thought if I lifted the car that I could see where it's scraping, but nothing. I took the wheels off and couldnt find anything loose or any metal on metal contact that would cause it. I replaced the wheels and decided to test my luck this morning. I did not hear a knock or any scraping this morning. It was colder this morning than last night so I don't know if this can be a factor. I did notice now that there is a faint knocking when I'm braking, and it only occurs around the 25-30mph and 0-15mph. It doesnt do it when I'm coasting, but just starts when I'm braking. I will check on it throughout the day, just to make sure it doesnt get worse like yesterday. Hopefully it's something I can wait on for parts, so it's much cheaper.

 

Do you think it could be the CV Joint or CV Axle? I didn't hear any knocking while turning today, whereas yesterday it was constant knocking noises while driving straight, turning, etc.

 

It could be something as simple as the brake pads. Did you get new ones with the brake hose work? If the old ones were put back on they could have been reversed so the inner is now the outer (which means they need time to seat properly) or maybe the little springs on the pads were bent or broken (pads have room to move too much).

I'm just guessing based on your description but it really sounds like something the mechanic did or didn't do. I'm guessing that it is not the CV axle.

 

Thanks for the advice. Ever since I've taken the wheel off and checked, the knocking has become more and more faint. They did not do brake pads or brake work when replacing the actual lines up front. I got my oil changed today and had them rotate the tires. NO MORE KNOCKING!!! I'm to a point of confusion now. The only thing I can think of was the tire being somewhat loose. I know when I took the tire off the first time, that it was really easy to take off the lug nuts. I do need to get my tires rebalanced.

 

I also do not know if I should even take it back in to check for a noise if the dealership didnt see anything wrong when they rotated the tires.

 

Sounds like the brake pads needed to re-seat. I'd just drive it and wait.

Having owned and driven the car for so many years I bet you know every squeak and rattle!

 

I planned on waiting until something happened. I've driven every year from CO to TX for holiday's and CO to WA for New Years. I hope I know every squeak and rattle. HAHA.

Sometimes it's good to know your car very well. Other times you get paranoid that it's worse than what it really is.