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Older Mercedes shudders when I go over 60 mph

I had my front and back struts replaced about 8 months ago. Before they were replaced the entire car would shudder violently when I went over 40 mph.



In the last week, my car has started shuddering badly when I go over 60 mph. Someone told me that my overdrive might be out. If that’s the case, I know it will be terribly expensive to fix. Any other suggestions?



Additional info: my brakes are metal-to-metal right now and are desperately in need of fixing. I don’t know if this could be contributing in any way to the shuddering by messing up alignment or something like that.



Please help!



-Grace

You need to get this looked at ASAP. There are anumber of things on an old car that could cause shuddering over 60 mph. You could easily have a suspension component ready to fall off. You drop a ball joint or a tie rod end and you’ll be in serious danger.

Your brakes are a very serious safety issue and need to be address whether or not they’re coontributing to the shuddering or messing with the alignment.

What year and model is your Mercedes? This may get you more precise troubleshooting on this forum.

One possibility: Check the amount of air in the tires. The PSI fill settings are listed on the door jamb and inside the gas filler door. If the rear tires have somewhat different amounts of air between the two this can cause shuddering, especially the faster you go.

Anohther possibility: The driveshaft may be loose. On my 1992 a flex disc is used instead of the traditional U joint to connect the driveshaft. Either way, if the shaft is loose it needs to be fixed soon and it is a relatively inexpensive fix. You don’t want the driveshaft to fall off the car.

Find a good independent mechanic that works on Mercedes and you will probably save a lot compared to the dealer–this has been my experience. But from what you’re describing I would get this looked at soon.

Reading your whole message tends to make me think that maybe maintenance on this car has been neglected over time. I suggest it is time to bring it into a good suspension shop and have them do a complete check including tyres and brakes and bring everything back to normal. Anything else would be a safety issue.

I agree with Mr. Meehan.

If someone is knowingly driving a car whose brakes are now in a “metal on metal” state, that tells us a lot about the owner’s approach to maintenance, as well as her concern for her own safety as well as the safety of others.

This vehicle needs to be gone over very carefully by a mechanic familiar with Mercedes vehicles, simply because deferred maintenance may have led to catastrophic failure of a component, and/or the imminent failure of more than one component. Just be sure to bring a credit card with a very high credit limit.