goober71

Hi,
I bought a 2014 CPO with 17K miles, with the extended warranty from the dealer, a couple of months back. Have done about 1K miles so far. I love the car, but i'm trying to make sure everything works as expected and there aren't any hidden issues that come up down the road.
When i'm driving at very low speeds (just starting off out of my driveway), with the radio off (to make sure i can hear clearly), i feel a slight hop or shake every second or so. Not MAJOR by any standards, just like a light bump. Once i speed up to over 20MPH, i can't feel it anymore. The steering is normal (no shake or pull at all). Trying to figure out if this is imperfections in the road (concrete surface) or tires/bearings on the car.
The tires are all in very good shape (as per the CPO guidelines, they had over 75% tread remaining when i bought the car).
Just wondering if this is normal, and if anyone else has seen the same.
Thanks!

G

apg231

Where are you feeling the hop? In the steering? Could the car have a flat spot on the tires? Have you had them checked for balance? Need a little more info on where you are feeling it to diagnose it further.

goober71

I feel it in the back. Almost like a slight jump and a sideways shimmy, if that makes sense.
I have not had the tires balanced. I assumed that by buying a CPO from the dealer, all the necessary checks and maintenance would be done prior to sale.
Thanks.

G

The G Man

Is it a 4matic?

apg231

that was my next question. The OP might be feeling the all wheel drive system. Not sure if he had driven an AWD vehicle before but they certainly drive different than a FWD or RWD.

goober71

no, it's RWD. But i've never driven a RWD either (all japanese FWDs till now :-)).
How about the rear suspension? Is it different than what a toyota or honda has? maybe that's why i feel it move differently?

G

apg231

I am sure the suspension geometry from a Honda/Toyota is way different than that of the Mercedes Benz you are referring to.

goober71

so, should i bother going to the dealer and getting it checked? Or just drive for a few more weeks and see if it gets any worse? Doesn't seem to be a commonly noticed issue on here.

G

apg231

If it's not too much trouble I would take it to another mechanic who you know and trust. Have them drive it and report back if anything "feels" weird to them. If you take it back to the original dealer they will try to assure you everything is fine. Doesn't hurt to get a second unbiased opinion.

goober71

that's a good suggestion. i'll try that. Thanks!

G