When is an oil dip stick considered a specialty tool and not a part?, asks Sir Tools. "When DaimlerChrysler decided not to include them on many of their vehicles." In response, the company offers 4 unique graduated measuring dip sticks for checking ATF or engine oil. While Mercedes vehicles will garner the most use of these tools, Sir states that many of the new Chrysler models use the same type of gear box. The company also reminds users that these dip sticks are not designed to be left on the vehicle.