my 2014 E350 4matic luxury has never been a great handling car but I always blamed the “extended mobility” tires it was equipped with. I changed them out about 6 months ago for Continental extreme contact dsw tires hoping that would help. It definitely quieted the road noise and they ride smoother but they seem even worse on the highway. The car wanders within its lane at about 65 - 70 and when you go to correct it will not react and then suddenly when you tweak wheel a bit more it will over correct and you have to turn the wheel back the other way. If it’s windy out at all its way worse.

Anyone else have have this Issue? My mechanic says he doesn’t see anything wrong with the suspension but I was wondering if maybe I put in some good quality aftermarket struts it might help. I have no interest in lowering the car and I would prefer not to stiffen the ride by a lot but the car isn’t fun to drive on the highway and it seems like it’s getting worse. This should be a great highway cruising car but I don’t look forward to long trips since you have to actively steer the car all the time. It has 42k miles on it and was aligned 6 months ago with the tire installation.

any suggestions or similar experiences welcome.

Hi and thanks for your reply. Sadly my car does not have adaptive cruise control and the lane assist is only passive, not active so we can rule that possibility out. The tires were purchased at Town Fair Tire in southern New Hampshire and were definitely “computer balanced” at the time of install. I will have to check and see if they offer free lifetime balancing, they offer quite a few other things. I don’t notice any thumping or vibration which you might typically expect from an out of balance tire but I’m not ruling anything out yet.

i really like the color but in dim light and when it’s not clean it can look like a dull grey.

i supose it might be worth trying even though it was just done 6 months ago. Maybe I’ll have my independent mechanic do it instead of the tire store.

you're in luck:
https://www.townfairtire.com/vehicle/tires/
They have free alignment as long as you buy tires from them.

What you describe is what I expected from this car and those tires. I think you and the others who questioned alignment may be on to something. The tire store may redo it for free but I might rather use my Indy since they have over 30 years experience with Mercedes. I’ll post back with results.

One other possibility is wheel bearings.

Interesting post guys I just got a 2011 and 350 sport package with 18 inch rims I’m coming from driving a 2004 8320 for the last 13 years The ride is completely differentThe new car is more stuff you feel everything and yes I noticed the same thing the car seems to drift slightly at higher speeds on the highwayI have a lifetime warranty so I got the car aligned it helped however I’m gonna take it back and see what else can be done because I feel like it’s still not 100%Adding nitrous to the tires instead of error made a huge interesting post guys I just got a 2011 and 350 sport package with 18 inch rims I’m coming from driving a 2000 4320 for the last 13 yearsThe ride is completely differentThe new car is more stiff you feel everything and yes I noticed the same thing the car seems to drift slightly at higher speeds on the highwayI have a lifetime warranty so I got the car aligned it helped however I’m gonna take it back and see what else can be done because I feel like it’s still not 100%Adding nitrous to the tires instead of air made a huge difference.

Okay, I didn’t mention the “only happens sometimes” part because I thought I must be crazy but that’s exactly right! Sometimes in heavy traffic on the highway it’s a white knuckle ride trying to keep the car in its own lane. Sometimes it seems fine, but less and less “good days”. Maybe it’s somewhr in the steering system, a low pressure condition in the pump or some other such thing. I don’t know but I really would like to get this resolved as I am stuck with this car for a while due to plummeting trade in values.

Need the alignment shop to hand you the printed camber and caster settings.

Outside edge of front tires being eaten is a problem and completely opposite of what should happen.

Took my old e500 in for alignment a few times at the dealer. The last time I took it in I used another dealership. It rode like brand new. The air suspension requires additional steps including a Romness tool, spreader bar, and weights. So I think a nonairmatic would require the last two, which most chain stores won’t have. As I understand, airmatic have to be at the dealership to adjust ride height with Star/Romness tool.

Camber / caster bolts are easy to be installed wrong. Did you get a printout of settings before and after changes? Call them if not.

Camber - Notches facing outward will reduce inside wear which is common. There is a line on the bolt. You should check if they are.

Caster - pulling back driver caster and pushing forward passenger caster will move car left. How did they install them? Check bolt lines. Passenger side line out and driver side line inward.

Only after this can the alignment shop do the only thing that they can do which is set toe.