1/2" Drive Long-Reach Convex 6-point Socket-17mm (NSB.17) - the Facom NSB.17 socket
is the original factory tool for safe and effective
removal of the convex ("flower
head") lug bolts on late model Mercedes S-class (W221), GLK-class,
M-class, CL-class and Maybach cars. The socket was included with the factory tool sets
sent to each Maybach dealer. Use of standard 17mm hex impact
sockets will likely damage these costly lug bolts. Also available
in 5-packs for additional savings. Surprisingly, very few
Mercedes dealers stock this item.
replacement (includes return shipping) when purchased
through Ultimate Garage. See comments below.
- this socket was constructed the same as Facom's standard deep
socket without the chrome plating. Since the wall thickness is a
full 2mm thinner than Facom's standard 17mm impact, it cannot
withstand repeated high torque and impact without eventually
cracking. With the use of a breaker bar for lug removal and a
torque wrench for tightening, the chance of socket failure is
reduced to near zero. If your impact gun has torque settings,
dial the setting back to under 200 ft lbs. Broken sockets can be
sent back to Ultimate Garage for immediate replacement ($15
charge per socket to cover shipping costs to France) or returned
directly to Facom in Europe.
- this socket intentionally has a looser fit (8-9 degrees of play
between the bolt and the socket) compared to the tight fit with a
standard hex socket (3-4 degrees of play). The thin polished
aluminum cover on the Mercedes bolts is easily deformed from the
torque and impact blows during R&R. Once the cover is
deformed, the tight fitting hex socket will no longer fit the
bolt. The convex socket will be now required to remove the lug
bolt. See photo details.
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