Mercedes-Benz Forum banner

1 - 20 of 36 Posts

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #1
So I bought my 2001 SL500 3 weeks ago with collapsed engine mounts and low tread tires. I drive it one hour back to home and had no vibrations. Week later vibrations started and only happened on the freeway at like 40mph + when driving on the bad parts.

I changed:
-both engine mounts (Corteco- I know not oem but they’re OE, and the only motor mounts sold on FCPEuro for my car, and I read Corteco is a good quality and German madthough fcp euro said made in China)

- Transmission mount (Corteco)

-New tires correct size and staggered (Previous owner simply threw on 245/45/18 on all four wheels)

Does anyone have any idea why I’m getting freeway vibrations still? Is it suspension related? Flexdisc?
 

·
Registered
1998 SL500 Pano
Joined
·
146 Posts
Have you got a bent rim and are you using spacers? Are rims correct offset for the car? Is the steering damper in good condition?
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #3
Have you got a bent rim and are you using spacers? Are rims correct offset for the car? Is the steering damper in good condition?
I had my exhaust looked at today, and the best mechanic there said he couldn’t see any rim bends. I don’t know what spacers are so I guess I don’t have them and rims are stock 18x8.5 18x9.5

steering damper I’m not sure of , will need to get it looked at
 

·
Registered
1994 SL500
Joined
·
2 Posts
Maybe a wheel weight came off since you had the new tires put on. Couldn't hurt to have them all rebalance again. Also a wheel could be bent and not always visible to the eye.
 

·
Registered
94 SL320 98 SL500 99 SL600
Joined
·
871 Posts
Tie rod ends and steering damper may be bad also control arm bushings. Does the vibration change with speed? Is it all freeways and smooth roads? Some freeways are pretty noisy.
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #6
Tie rod ends and steering damper may be bad also control arm bushings. Does the vibration change with speed? Is it all freeways and smooth roads? Some freeways are pretty noisy.
Vibrations only happen on the freeway on the bumpy messed up lanes when I go from 40mph+. If I change lanes to a smoother lane itle go away then come back again the second the lane gets bumpy

When on the streets no vibrations even with bumps and cracks

FYI I live in Southern California and the roads are horrendous
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #7
Maybe a wheel weight came off since you had the new tires put on. Couldn't hurt to have them all rebalance again. Also a wheel could be bent and not always visible to the eye.
Would you recommend a wheel alignment as well?
 

·
Registered
94 SL320 98 SL500 99 SL600
Joined
·
871 Posts
Vibrations only happen on the freeway on the bumpy messed up lanes when I go from 40mph+. If I change lanes to a smoother lane itle go away then come back again the second the lane gets bumpy

When on the streets no vibrations even with bumps and cracks

FYI I live in Southern California and the roads are horrendous
I too live in SoCal and some of the freeways are rough I get the same vibrations in all three of my SL's and they are all in new condition. Love to travel NV and AZ, great fast roads. 60E is real bad but I ain't tried it since the repairs. Parts of 215 shake ,15 south of Corona will take your turn signal lenses off, lost two on that one. Some tire brands suck Sumitomo will drive you nuts with noise also Hankook after a couple thousand miles. I think you need to address all the bushings and ball joints. How many miles on your car
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #9
I too live in SoCal and some of the freeways are rough I get the same vibrations in all three of my SL's and they are all in new condition. Love to travel NV and AZ, great fast roads. 60E is real bad but I ain't tried it since the repairs. Parts of 215 shake ,15 south of Corona will take your turn signal lenses off, lost two on that one. Some tire brands suck Sumitomo will drive you nuts with noise also Hankook after a couple thousand miles. I think you need to address all the bushings and ball joints. How many miles on your car
75,100 miles currently. I know my ball joints are smushed cause my local mercedes Indy showed me and told me that’s why my brakes creak when pressing/releasing

This vibration issue is so annoying and surprising given I drove on the horrible 10 freeway to get back to Riverside with collapsed engine mounts and old tires after purchase and ride was pretty good
 

·
Registered
94 SL320 98 SL500 99 SL600
Joined
·
871 Posts
75,100 miles currently. I know my ball joints are smushed cause my local mercedes Indy showed me and told me that’s why my brakes creak when pressing/releasing

This vibration issue is so annoying and surprising given I drove on the horrible 10 freeway to get back to Riverside with collapsed engine mounts and old tires after purchase and ride was pretty good
See if 40lbs rear and 37lbs front help any. I have the same wheels as you my tires are 245/40 front and 275/35 rear
 

·
Registered
1994 SL500
Joined
·
2 Posts
Would you recommend a wheel alignment as well?
If you've changed the tires to the correct sizes I would get a wheel alignment. Does it pull or wander to one side more than the other? If so get it aligned. Also check your tire pressures. It could be something simple and inexpensive. Compared to changing out all kinds of parts hoping you find something.
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #12
If you've changed the tires to the correct sizes I would get a wheel alignment. Does it pull or wander to one side more than the other? If so get it aligned. Also check your tire pressures. It could be something simple and inexpensive. Compared to changing out all kinds of parts hoping you find something.
After paying attention to my driving today, I realized that I’m not necessarily vibrating but my front end is rocking/jumping up and down even at low speed stop and go on the freeway....
 
Joined
·
1 Posts
So I bought my 2001 SL500 3 weeks ago with collapsed engine mounts and low tread tires. I drive it one hour back to home and had no vibrations. Week later vibrations started and only happened on the freeway at like 40mph + when driving on the bad parts.

I changed:
-both engine mounts (Corteco- I know not oem but they’re OE, and the only motor mounts sold on FCPEuro for my car, and I read Corteco is a good quality and German madthough fcp euro said made in China)

- Transmission mount (Corteco)

-New tires correct size and staggered (Previous owner simply threw on 245/45/18 on all four wheels)

Does anyone have any idea why I’m getting freeway vibrations still? Is it suspension related? Flexdisc?
Could be the way they tightened the flex disk but it's probably the way they tightened the mounts on the sides and back of the trans under the car. You have to tightened certain ones down first otherwise it'll vibrate
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #14
Do you kno
Could be the way they tightened the flex disk but it's probably the way they tightened the mounts on the sides and back of the trans under the car. You have to tightened certain ones down first otherwise it'll vibrate
Do you know if I can can diagnose the flex disc to see if that’s the culprit?
 

·
Outstanding Contributor
R129 500 SL 1991
Joined
·
892 Posts
You would need to get underneath and inspect flex disc. If it’s cracked, it’s a gonna.

Logic suggests the vibration is either due to the new Chinese engine mounts or new tires, because you wrote that vibration wasn’t there before. Presumably mounts and tires were done at same time?

Who diagnosed that the engine mounts had failed? And do you know how they arrived at that conclusion?

So, working this through... in my mind... you had the tires changed. So, if the wheels were out of balance at 40+ it would vibrate on smooth and rough highway, so it can’t be that.

You wrote that front rocks up and down... so my guess is that when you bought the car and drove it home, the old tires were maybe under-inflated, masking problem with front shocks. New tires would be stiffer and pumped up. Problem with front shocks no where to hide. All is laid bare? I let you decide.

If it were me, I would entertain the following possibilities: -
  • knackered front shocks (struts) and/or bad strut top mounts;
  • possibly bad/incorrectly fitted engine mounts (first retighten in correct order as per previous post; then park car, hood open, brakes on, select reverse and apply slight throttle - does engine lift noticeably?);
  • possibly steering damper or idler (tell tale slow speed vibration through steering wheel when going over speed hump?);
  • possibly flex discs (easy check for cracks).
  • Front anti-roll bar (torsion bar) bushes worn (check for play with pry bar)
 

·
Registered
2001 SL500
Joined
·
32 Posts
Discussion Starter #16
You would need to get underneath and inspect flex disc. If it’s cracked, it’s a gonna.

Logic suggests the vibration is either due to the new Chinese engine mounts or new tires, because you wrote that vibration wasn’t there before. Presumably mounts and tires were done at same time?

Who diagnosed that the engine mounts had failed? And do you know how they arrived at that conclusion?

So, working this through... in my mind... you had the tires changed. So, if the wheels were out of balance at 40+ it would vibrate on smooth and rough highway, so it can’t be that.

You wrote that front rocks up and down... so my guess is that when you bought the car and drove it home, the old tires were maybe under-inflated, masking problem with front shocks. New tires would be stiffer and pumped up. Problem with front shocks no where to hide. All is laid bare? I let you decide.

If it were me, I would entertain the following possibilities: -
  • knackered front shocks (struts) and/or bad strut top mounts;
  • possibly bad/incorrectly fitted engine mounts (first retighten in correct order as per previous post; then park car, hood open, brakes on, select reverse and apply slight throttle - does engine lift noticeably?);
  • possibly steering damper or idler (tell tale slow speed vibration through steering wheel when going over speed hump?);
  • possibly flex discs (easy check for cracks).
  • Front anti-roll bar (torsion bar) bushes worn (check for play with pry bar)
Before purchase three weeks ago, I had a Benz shop inspect the car, which went on for about an hour. They determined engine mounts were completely collapsed(was true as when I had the three mounts done, I saw the old collapsed mounts, and the tranny mount had minor tears though inspection never noted them to be bad) and I needed new tires.

The strange vibrations started a week after purchase, so I changed the three mounts. Still vibrating freeway only. Changed tires still happening.

I tried the engine jump test on Thursday but in park. I’ll try in reverse.

FCPEuro only sold the Corteco engine mounts for my year and model and it said OE so I figured what the hell... Tried to find Corteco reviews got a ton of BMW pages and people said they were good..

and isn’t Lemförder built in China as well?
 

·
Registered
M113 SL500
Joined
·
466 Posts
I never found the R129 to ride particularly well on rough roads and I've replaced all wearables on my car and had it properly aligned. Perhaps you're expecting a typical wafty Mercedes sedan ride?
 

·
Outstanding Contributor
R129 500 SL 1991
Joined
·
892 Posts
...The strange vibrations started a week after purchase, so I changed the three mounts. Still vibrating freeway only. Changed tires still happening...
Ok, I misunderstood. So you changed mounts and tires after vibrations started. Did you pump up the old tires before vibrations started? Inflating soft tires can make a big difference to ride.

Sounds like the roads in So Ca are a challenge. Maybe even after a front end refresh, those roads would still reveal the true nature of the R129, along the lines of what Brauhaus suggests?

I second replacing the ball joints and bushes as @FATHERTIME suggests, but probably time the front struts and top mounts were replaced as well.
 
1 - 20 of 36 Posts
Top