AMGRay

As some of you know, my newly acquired GLB250 is in the shop waiting on a back ordered replacement head. So now I'm wondering how reliable is the new replacement head for the GLB 250? Has anyone had their head replaced and put any decent miles on it like say 20,000 miles?

Thanks

Odd Piggy

The head on our GLK250 failed and turned on the CEL at 27,000 miles and we now have 43,000 miles. All okay so far. FWIW — The service manager says that Mercedes knows where the defect is and it won’t happen again. My SA says that Mercedes is covering the replaced heads for the life of the vehicle, but I can’t find anything online about it.

The best I can find says 2 years just like all the other repairs.
https://www.mbusa.com/content/dam/mb...20Warranty.pdf

The_MDA

2020 with AMG line is my car. No major issues this far - 30,500 miles - however of late the car struggles to start when it’s been sitting, especially overnight. Am I about to get bit by the cylinder head bug?

Also, good luck getting an OEM windshield replacement. I’ve been waiting since mid-January and nothing in sight. Multiple dealers telling me there is no stock anywhere and they potentially changed suppliers. I gave up and am just getting aftermarket.

Odd Piggy

Our C250 showed no symptoms other than the CEL. It started and ran fine. 75-80 MPH highway was no problem.

As for the windshield, I suppose getting an OE would be a must for a classic to keep it all original. But for a people/grocery hauler, a quality aftermarket windshield should be fine. Just avoid the Chinese budget brands like Benson, because they can have noticeable visual distortion.

AMGRay

Thanks,

I'm about to go pickup my car with its new cylinder head. I'm hoping the new head is designed better.

ILoveNY

what about off-lease GLBs? if the head is fine for the first 30k then it's fine or it may fail later?

Vladimir Livson

There is always a chance that it can fail later, if it was not replaced during the lease. Should be covered under 4 years / 50K miles warranty, after that you on your own. Unless they issue a Recall Notice, like they did in Canada.

Serhan

"The cylinder head was replaced the first time at 15000 miles, the second time at 29000 miles." per below post:
2021 GLA250 cylinder head replaced twice

AMGRay

Does the GLA and GLB have the same 4cl? That will sucks if so, my son has a GLA 45.

So far it doesn't seem too common on the second head. Still not sure if I want to ditch my GLB 250 for something else.

E55Greasemonkey

I predict MB will issue an extended warranty for these cylinder heads 10yrs/120k miles like they have for other models with similar design (assembly) flaws.

Serhan

They have the same engine, but GLA45 has AMG hand built engine in comparison to GLA/GLB 250/35 models. Also certain production years during covid has the problem due to parts, etc. Yes, not common in 2nd head.

They extended the engine warranty in Canada, not in US:
https://mbworld.org/forums/glb-class...nder-head.html

ILoveNY

is the GLB35 reliable or its engine head has similar issues?

E55Greasemonkey

Same problem.

ILoveNY

I hope they do it in the USA

Purekoryo

Had the cylinder head replaced due to cracked exhaust valve around 20K or more miles and now at 31K it’s showing symptoms again.

We have a 2021 GLB 35 AMG. Anyone know if it has the extended warranty for the cylinder head in the US?

Vladimir Livson

Yes. Refer to Warranty Repair Cylinder Head on this forum.

https://mbworld.org/forums/glb-class...nder-head.html

Odd Piggy

OMG — My 2021 GLB250 failed at 27k and is now at 55k. Yes there is an extended warranty in the U.S. But your GLB must be showing some very specific trouble codes to be covered. However, you should not have to worry because you’re still covered by the 4 year - 50,000 mile new car warranty.