What size hex is required to remove the caliper bolt on a 2006 Mercedes ML500?

Probably 17, 18, or 19.

Mercedes specifies to not reuse these bolts but rather to replace them with new ones.

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Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

I think this size is too big. I am thinking it is a 9mm which is a very odd size. If anyone knows for sure please respond!

Yes, 9mm inhex to remove the pads.

Probably 17 or 19 hex to remove the caliper.

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

And 7mm - another odd ball size - to do the rears.

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1973 280SE 4.5 (Sold)
1984 LWB 280GE (Sold)
2000 G500 NMLE - "Deep Throat"
2007 ML320 CDI (Sold)
2010 Porsche Cayenne S Transsyberia TipTronic (Sold)
2010 Audi Q7 3.0 TDI (Sold and Sorely Missed)
2014 ML350 BTC
2015 Audi Q7 3.0 TDI (On Order)

Yes, this 7mm stuff started, I believe in the 1990s--have also seen it on Volvo and VW.

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles