Hi All. Yesterday my car was making an unusual thud or tug or pull whenever I turn to either side (left or right) when moving forward or back but not when going straight. It seems like it's catching on to something when steering left or right. I inspected all the mechanical components connecting to tire and found none loose or any rubbing. Has anyone had this problem? Any ideas what could be potential issue? Thanks.

Possibly the CV joint , take it to a place where they will test drive it with you and show you the problem. Most big muffler brake shops will.

thanks for the tip, i'll look into that

Is yours a 4Matic? If so, my thought is check the front diff as well. I would also have the steering system checked: all linkages connected to the steering as there may be some wear that's causing it to catch.

Yes it is 4Matic, 2010 with only 43,000 miles on it. No grinding, clicking or growling noise but like a thump/thud when turning either way. I've checked the linkages, control arm, CV joint boots, bushings - all seem to be good, no tears, not even sign of rust anywhere. very puzzling. i was wondering about the steering column too if there is a coupling that could be getting loose? Have not replaced steering columns before so not sure about it. Will take to a hopefully honest shop who can pinpoint problem and see if it's doable fix. I hate to buy parts and find out it's not the issue. Thanks for the tip.

I wonder if yours is covered by the recall affecting some steering bolt. Ours is but I haven’t gotten it in the shop for the free repair yet.

Maybe do a quick VIN search on NHTSA site or MB site to see if yours is included?

Sorry for the long silence/response, got tied up with fixing my other vehicle brakes. Got that fixed and out of the garage so on to the next.
Update on the GLK350, I test drove it again and was feeling that the car was stuttering while driving and got worse as you accelerate. It does go away when decelerating or easing off the gas. Took it to the dealer and their diagnosis was bad transmission and torque converter - they both have to be replaced. My first reaction was, WHAT!!! But it only has 44,000 miles (43,000 was typo), how would that be failing too soon? MB response was it was out of warranty (4 years or 50,000 miles) they can't do anything. Dealer(Stealer) quote was about $8300 to replace transmission and torque C. I did see some videos about the transmission solenoids and conductor board failing which are easier and cheaper to replace but none mentioned about the stuttering symptom. I wonder if those could be cause of the problem before i dive in to spend more money. Has anyone experienced this before or any knowledge of these components symptoms when they fail?

Before spending that kind of money on a 10 year old car, I would get a second and third opinion. I can't see the transmission and the torque converter both failing with that little mileage.
You could even try changing the fluid and filter. Kits are available from FCP Euro for around $220.
Stuttering is very often caused by an ignition issue causing a misfire. Specifically a bad ignition coil. Does the stuttering get worse the harder you accelerate? This is usually accompanied by a check engine warning light though after driving it that way for some distance.

Its been a well documented problem with that generation of GLKs. Unfortunately its an expensive fix, but you can have the transmission, differential and torque converter rebuilt by a shop rather than MB. I don't have this problem on my 201e GLK, but when I inquired about a full rebuild, they quoted me around 2,200 CDN to rebuild and install the transmission. Not a bad deal..

What kind of stuttering ? Usually that’s fuel or ignition related . Did a regular non Mercedes mechanic look at it?

Thanks for the inputs. I did bite the bullet and spent the money to replace the transmission and torque converter - but not from the dealer. I'll give a plug in for AAMCO here in Connecticut who did a good job and reasonable price. To compare, the dealer wanted $9800 with 1 year or 12,000 mile warranty. While AAMCO did it for $5200 with 3 years and unlimited miles, plus they did oil change, belt and tensioner, and replaced front brakes on top of that. Stay away from the dealer (stealer) at all costs if you want to save some money.

The stuttering feeling/symptom is somewhat similar to a miss fire. A quick way to check fuel delivery and electrical system firing is revving the engine while parked if there's any hesitation or unusual (not smooth) rev of the engine - there wasn't any so I kinda ruled that out. Then I did drive up to a shop for quick diagnostic.