2001 Cl500 noises....
03-15-2018, 06:55 PM
#1
Junior Member
Thread Starter
2001 Cl500 noises....
Hey everyone,
So ever since I bought the car I noticed a loud rattle sound when the car is in motion. I cant seem to replicate it when revving the car when parked. Only when cruising around town. I put the car on a lift and did the test with a rubber hammer and confirmed that 2 of the cats are going bad (slight rattle when tapped). I just making sure that before i go and replace the 2 cats (passenger side primary and secondary) that its not something else that could be making the noise. I have checked the bolts on the heat shield for the exhaust and all bolts were tight nothing loose. I also checked the flex discs and center support bushing for the driveshaft and all checked out good.
So before i go and have them replaced do you think its possible that something else could be making the loud rattling noise? I thought cats since i confirmed 2 are starting to fail but I'm starting to think the rattle is way louder than what those cats made when smacked with a hammer. Could it be the rear brakes chattering? I do plan to replace the rear wheel bearings since I'm also dealing with a loud howling noise from the rear when I'm driving 30 mph or faster. Its the worst at 50 mph and seems to quiet down a little bit at 60 mph and up.
My plan of attack is as follows:
Replace the passenger side cats (Possibly do a muffler delete since I'm there anyways? Not sure how bad the drone will be in the cabin.)
Replace the rear wheel bearings
Flush the rear diff and refill with fresh fluid (When i checked the fluid before it was very black and pretty old)
I know a lot of people say howling noises can happen due to the ABC system. I have already converted the car to strutmasters and looped the tandem pump back to reservoir. I have not yet removed the old accumulators or valve blocks tho. Could they still be causing the howling noise even tho they are not being fed by the system anymore?
Any help on this is much appreciated. I figure at least if i get this all done i know it wont have to be addressed anymore and hopefully the noises are gone but who knows. Oh yeah the car has about 167k miles so i figure its about the time in its life for all these things to fail. Also to add onto this I have directional Z rated tires on the car all around (previous owner installed them before sale) and i have heard that they can make a lot of noise but the howling noise is so loud you cant hear anyone talking if they are in the back of the car. Its super annoying!!
- Logan
So ever since I bought the car I noticed a loud rattle sound when the car is in motion. I cant seem to replicate it when revving the car when parked. Only when cruising around town. I put the car on a lift and did the test with a rubber hammer and confirmed that 2 of the cats are going bad (slight rattle when tapped). I just making sure that before i go and replace the 2 cats (passenger side primary and secondary) that its not something else that could be making the noise. I have checked the bolts on the heat shield for the exhaust and all bolts were tight nothing loose. I also checked the flex discs and center support bushing for the driveshaft and all checked out good.
So before i go and have them replaced do you think its possible that something else could be making the loud rattling noise? I thought cats since i confirmed 2 are starting to fail but I'm starting to think the rattle is way louder than what those cats made when smacked with a hammer. Could it be the rear brakes chattering? I do plan to replace the rear wheel bearings since I'm also dealing with a loud howling noise from the rear when I'm driving 30 mph or faster. Its the worst at 50 mph and seems to quiet down a little bit at 60 mph and up.
My plan of attack is as follows:
Replace the passenger side cats (Possibly do a muffler delete since I'm there anyways? Not sure how bad the drone will be in the cabin.)
Replace the rear wheel bearings
Flush the rear diff and refill with fresh fluid (When i checked the fluid before it was very black and pretty old)
I know a lot of people say howling noises can happen due to the ABC system. I have already converted the car to strutmasters and looped the tandem pump back to reservoir. I have not yet removed the old accumulators or valve blocks tho. Could they still be causing the howling noise even tho they are not being fed by the system anymore?
Any help on this is much appreciated. I figure at least if i get this all done i know it wont have to be addressed anymore and hopefully the noises are gone but who knows. Oh yeah the car has about 167k miles so i figure its about the time in its life for all these things to fail. Also to add onto this I have directional Z rated tires on the car all around (previous owner installed them before sale) and i have heard that they can make a lot of noise but the howling noise is so loud you cant hear anyone talking if they are in the back of the car. Its super annoying!!
- Logan
Last edited by Maclogos; 03-15-2018 at 07:02 PM.
03-16-2018, 06:33 PM
#2
Junior Member
Thread Starter
So update time....
I called the local exhaust shop and they quoted me 520 for new primary and secondary cat for the passenger side. Walker brand and not high flow. I'm thinking that's a bit much to pay for aftermarket non high flow cats. My new plan is to go by there and see how much to just replace the passenger primary and delete both the secondary cats and keep the stock mufflers in place.
Im not expecting a huge increase in noise since I'm gonna keep the mufflers but i will definitely save some money by deleting the secondaries instead of overpaying for a replacement. I live in CA so i know there is risk of not passing Smog inspection but really i havn't seen a tech get under the car to count the cats and they don't do a sniffer test on 00 and up here. Should be all good and hopefully i save a bit of money. Will report back after.
Sadly.... I'm not able to make the time this weekend for the rear diff, front ball joint, and wheel bearing replacement. That gonna have to wait till next weekend.
I called the local exhaust shop and they quoted me 520 for new primary and secondary cat for the passenger side. Walker brand and not high flow. I'm thinking that's a bit much to pay for aftermarket non high flow cats. My new plan is to go by there and see how much to just replace the passenger primary and delete both the secondary cats and keep the stock mufflers in place.
Im not expecting a huge increase in noise since I'm gonna keep the mufflers but i will definitely save some money by deleting the secondaries instead of overpaying for a replacement. I live in CA so i know there is risk of not passing Smog inspection but really i havn't seen a tech get under the car to count the cats and they don't do a sniffer test on 00 and up here. Should be all good and hopefully i save a bit of money. Will report back after.
Sadly.... I'm not able to make the time this weekend for the rear diff, front ball joint, and wheel bearing replacement. That gonna have to wait till next weekend.
03-19-2018, 12:55 PM
#3
Junior Member
Thread Starter
Another update.... Replaced the passenger rear cat and the rattle is still there. Yesterday i went out to the car and started to shake the mufflers with my hand and found that the drivers side muffler has a piece of debris in it and it causing a loud rattle. Most likely a piece of the cat that probably made its way into the muffler or the baffle inside the muffler has started to come apart as well. Wouldn't be surprised since this car is 17 years old. Gonna take the car today to have the mufflers deleted and hopefully that's the trick to no more rattles on this car. Wish me luck haha.
I will be sure to report back with results. I did finally get around to replacing the mirror gaskets and found a nice little spider that was taking residence in my drivers side mirror housing. Not having the right length torx made this job nearly impossible to do but it was eventually taken care of.
I will be sure to report back with results. I did finally get around to replacing the mirror gaskets and found a nice little spider that was taking residence in my drivers side mirror housing. Not having the right length torx made this job nearly impossible to do but it was eventually taken care of.
03-19-2018, 01:56 PM
#5
Junior Member
Thread Starter
03-19-2018, 05:59 PM
#6
taking off one won't make it drone
03-20-2018, 12:22 PM
#7
Junior Member
Thread Starter
Driving me crazy!!
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03-21-2018, 10:45 AM
#9
Junior Member
Thread Starter
That’s interesting. I’m gonna have my mechanic check it out when he does the rear wheel bearings. In my case I pick up speed faster than 20mph then the rattling begins. I can’t replicate the noise when revving the engine at stand still. Only in motion above 20mph the rattle noise happens.
Now I’m ordering a new thermostat.... It's always something but lucky it’s been small stuff and fairly inexpensive so far. Car takes over 15 miles to reach operating temp (80c -95c on the gauge) but if I turn on my heater the needle will drop to under 70c. Pretty sure it should be maintained at 80c lowest. Eating a lot of gas due to this most likely. Getting roughly 16.5 estimated mpg on the highway cruising at 65mph. It should be better than that!
Now I’m ordering a new thermostat.... It's always something but lucky it’s been small stuff and fairly inexpensive so far. Car takes over 15 miles to reach operating temp (80c -95c on the gauge) but if I turn on my heater the needle will drop to under 70c. Pretty sure it should be maintained at 80c lowest. Eating a lot of gas due to this most likely. Getting roughly 16.5 estimated mpg on the highway cruising at 65mph. It should be better than that!
Last edited by Maclogos; 03-21-2018 at 01:35 PM.
03-21-2018, 10:46 AM
#10
Junior Member
Thread Starter
Oh and after the muffler delete I did notice a pretty significant loss in low end torque. Having to give it more gas now at lower rpms but it’s worth the trade off for the awesome sound!
03-25-2018, 11:12 AM
#11
Junior Member
Thread Starter
Update time! Huge win yesterday! Checked the rear wheel bearings and my rear passenger bearing was completely shot. Was able to cheat a bit by making some custom bearing pullers and was able to change out the bearing without having to remove the hub. Took a few hours but got it done.
No more humming noises or rattles! I thought my cats were done but turned out the wheel bearing was also chattering so much it sounded like failed cats. $50 bucks for new bearings and a few hours cursing at the shop turned into a huge success. For anyone that is wondering what is causing a rattling noise, make sure to check your wheel bearings!
I also went went ahead and changed out my third brake light (new assembly) and also changed all the interior lights and license plate lights to white led. Swapped out my drivers side mirror (auto dim fluid was showing through the glass really bad) with a made in China, heated, wide lens glass and it looks like new. Just gotta wire in the heated function. New hood badge for good measure as well haha.
Now the car car is super quiet and I can hear my awesome exhaust! Now just small things to fix but overall very happy!
No more humming noises or rattles! I thought my cats were done but turned out the wheel bearing was also chattering so much it sounded like failed cats. $50 bucks for new bearings and a few hours cursing at the shop turned into a huge success. For anyone that is wondering what is causing a rattling noise, make sure to check your wheel bearings!
I also went went ahead and changed out my third brake light (new assembly) and also changed all the interior lights and license plate lights to white led. Swapped out my drivers side mirror (auto dim fluid was showing through the glass really bad) with a made in China, heated, wide lens glass and it looks like new. Just gotta wire in the heated function. New hood badge for good measure as well haha.
Now the car car is super quiet and I can hear my awesome exhaust! Now just small things to fix but overall very happy!
Last edited by Maclogos; 03-26-2018 at 03:09 PM.
