I'm trying to isolate this resonating vibration I have on the w210 e300D between 65-75 mph. Long story -- Its been there since i had it and i've been trying things as i've driven it the last year. i thought it was just the tires because they had some flat spots where someone skidded. But they were 80,000 mile michelins with only 40,000 miles on them. So i wanted to get more miles out of them. I thought it may be a warped disc rotor. They needed changing anyway so i did that and had it aligned at this local mexican alignment shop I like. They have a nice machine and let me work with them. it Didn't help. Rotating tires seemed to change it a little but then it came back.

Last week I changed out the tires with a good looking set of used ones from the same tire place that did the alignment. It definitely helped and changed the situation. Now it really oscillates mainly when you hit a bump to trigger it. The steering will will just keep vibrating and. Once you get to 80 though it smooths out and feels like it should.

I put it on the lift and checked all the suspension and everything and it all feels good -- tie rods, ball joints, axles.

One thing to note is I got tires that are a little taller. P215/60 R16 instead of P215/55 R16. Thats the only ones they had. I just had a thought that maybe that changed the alignment and it needs to be realigned.

I also wonder if the motor mounts could cause this. Them and trans mounts were replaced at 150,000 miles at a local indie shop. I can shake the engine with my hand though and it rocks pretty good. But it doesn't move when its idling. You see it rock good when you shut it off as it shudders to a stop. I felt the back sides of the motor mounts and they are soft on top. Anyone know a good tell tale sign motor mounts are bad? Does it sound like they could be collapsed? Yesterday, It seemed when i put on brakes, something surges forward but it could be in my head. Made me think bad mounts. I'm going to drive it here in a minute to work and see if i feel it.

I checked the flex discs too . They show a little cracking but none are busted. i am going to order some of those.


So in summary -- oscillations between 65-75 mph especially triggered by hitting bump . Any ideas?

Thanks

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

Deskpite your inspection that is one of the sypmotoms of something worn or loose in the front end.

I am suprised the place you did then alignment did not inspect too much play in the Wheel Bearings or other loose Joint issues.

It is possible to have multiple problems going on but I don't think the Engine is going to make your Steering Wheel do what you said it did.

Some of the Newer then 1985 Mercedes have issues where part of the Suspension Frame can get rusted through.

A change int he diameter of the Tires does change the alginment. I am less sure if wider or narrow Tires do that.

I would google "Now it really oscillates mainly when you hit a bump to trigger it. The steering will will just keep vibrating and. Once you get to 80 though it smooths out and feels like it should." and see what you come up with as a general cause of that problem.

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84 300D, 82 Volvo 244Gl Diesel

I am looking at a generic source and beside what was mentioned they list worn Socks (I assume Struts can do the same), it said steering knuckle Busing but I am going to say idler arm bushing, stabalizer bar issues, and what if your Steering Box or Rack is worn.

If you can find someplace that does it for free have the suspension check there. A Shop that is looking for work is going to take a very hard look at your suspension.

If they find something you don't have to have the work done there. Just ask for an estimate and tell them you don't have the Money to fix it right now and get out of the Shop.

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84 300D, 82 Volvo 244Gl Diesel

Did you check the tire dates when you bought the used tires?

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92 e300d2.5t
01 e320
05 cdi
85 chev c10

What are the total miles on the car??

Things that can cause what's happening - in addition to the suspects you think are cleared up:

Steering linkages

Has car been wrecked, or clipped? Are you certain of your answer?

Engine mounts are checked by their remaining thickness of MMs.

Flex discs are suspect.

Rear-differential mount - suspect.

Transmission mount - suspect.

Improperly installed (loose) wheel-bearings.

Worn suspension parts/bushings.

the lower ball joints can cause this and to some extent the uppers too. This is intensified if the front bushing of the lower control arm is completely shot. This starts an oscillation.

I had a similar experience in my W124 where the car would go into a death shake at 60 mph and the culprit were the lower ball joints. Both were shot beyond belief. New joints tightened up the car. The tires were the items that threw it into the death shake, the ball joints then played along. With new ball joints I would then get the steering shimmy vibration of bad tires and I eliminated that with new tires.

These cars have the nice old school front bearings (the one you packed every year on ol american cars). It never hurts to repack them with fresh grease and set them correctly, Sloppy bearings are a nuisance.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

On my daily driver (not a Mercedes, see sig) I had the same issue. Every time I hit a bump I'd have a rattling vibration going through the car and the vibration was there constantly at speeds between 60 and 70 mph. Almost felt like a cupped tire. Above and below those speeds the vibration wasn't there.

Anyway, long story short: Turned out to be the rear shocks. The shocks looked fine, and when pushing the car firmly down at the rear, it wouldn't bounce at all so they didn't appear worn out, though the dust boots were completely rotted off.

Still though, replaced shocks and dust boots and no more vibration. Well, in all fairness: I had the dealer replace those items, I didn't feel like dealing with a spring compressor.

Again, my daily driver is not a Mercedes, but I thought I'd share this with you since your symptoms seem to be the same as I experienced, and I was dealing with it for 2 years...

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"The MB W123 is so bulletproof, you can drive them forever. Which is a good thing as it takes that long to get anywhere."
Betsie: 1984 W123 300D (hobby, 280k miles)
Myrla: 2001 Mazda Protege 2.0 ES 5spd (daily driver, 130k miles)
The Turd: 2007 Toyota Camry (wife's car, 118k miles)

I'll second the vote for front bearings, but lots of suspension / tire problems can cause what you describe. Start simple/cheap and work toward complex. Use the test procedures in the service manual (WIS online in this case) to eliminate possible causes like ball joints, idler arm, front struts or rear shocks.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I'm going to bet on the sway bar bushings and/or links...about as cheap and easy to do as there is on this list. I'd did them on the passenger side and noticed some difference. My vibration range is about 10mph less than the PO's.

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Treetops
06 E320 CDI 127K Miles
87 300TD 231K Miles

99 E300 269K Miles-Sold

is that the car that rust,and the front wheels can fall off.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Yup.......

This is the answer I'm thinking. Thanks. When they did the alignment we did check suspension and bearings. We adjusted one. It is time for a repack or replace. I love these bearing systems. So easy. I'll check everything closely but the problem was different before the tires were replaced. It was more wobbly at 60 plus and not oscillation. the new tires which I'm happy with for the 140.00 I paid out the door and have lots of even tread, ride probably really nice. I think having those fixed revealed this other very consistent problem.

I don't recall a record of ball joints being replaced. Also that fits with the shifting feeling I feel when breaking hard. But I didn't notice it today. Car has 220000. I'll check close and take some pics. Looks like some suspension fun is in order. This car rides so smooth otherwise and isn't rusty at all and spring perches look good. I'm betting ball joints.

Thanks

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

From all of the Posts I have read it seems like a better check of all of the Front End cpmponents is in order and perhaps the rear.

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84 300D, 82 Volvo 244Gl Diesel

the lower joints on these cars are a weak point, good thing about their repair is that they are very easy to do.

while at it, get a jar of grease and repack the wheel bearings if they are not noisy or have no signs of damage like heat or metal dust (any grease claiming disc brake wheel bearings will work) - its best to do this all at once as removing the joints without the brake and hub in the way would be a piece of cake.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Glad to hear it. No pressing in and out needed it doesn't look like. I may have to run to the dealer to get them tomorrow. I'm excited to get this fixed. Hopefully with my shop discount they will be only about 30 or 35.00. I got a cool lyle bearing packer i used on a w124 a few months ago. I'll probably just grab new bearings too. But maybe not . Mine spin and don't make any noise and i don't feel grumbling.

I went through all the maintenance records for the car I have from the PO at one shop and they totalled $12,250. No record of ball joints or tie rods. The motor mounts and trans mount were just done at 196,000 so that was 25,000 miles ago. They are good i'm sure.

Pelican has lemforders for 29 and that karlyn brand. I got some karlyn tie rods for a w124 and they seemed good. If its an easy job it may be worth trying.

Thanks.

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius