johnnyG55

My CLK63 is nearing 50k miles. It's primarily for spirited summer driving.

I'm trying to decide if this is the year I finally upgrade the head bolts as preventive maintenance. I plan to keep this car long-term.

So, anyone out there at the 50k mark and still driving with original head bolts?

Should I go with OEM at the dealership or aftermarket (ie RENNtech)?

JPMD

This is a question I also have.
my new to me approx 3 mos CLK BS has 47K miles. She is doing great and has been well taken care of and serviced prior to my ownership however there is no documentation of head bolts being done.

ET550

I have 71K miles on mine with original headbolts and I am the original owner. No current plans on doing headbolts and am not aware of any BS owners having headbolt issues. There were some old TSBs posted in another thread trying to show that BS engines predated the head bolt issues. Only maintenance issues I have had after 50K miles were replacing the motor mounts and one of the fuel pumps.

Doctodd33

it's an overblown problem.....i.e. not really a problem

NYC_Z06

Low risk/catastrophic consequences. So the incidence of occurrence is rare, but when it happens it's a very expensive repair. Kinda like homicide stats in NYC.

PJK

I've got about 93k miles on mine, original head bolts.

borgreko

58k miles on my CLK63 B.S. factory head bolts with no issues, know a few cars with the M156 with over 160k still with factory head bolts.