Our C300 Sport came with these beautiful 18" AMG wheels, the merits and liabilities about them has already been discussed by many of you, but there's one facet to them that may have been overlooked. That big / ///AMG block cast into the wheel is directly opposite the valve stem. Wonder why?
A few months back, our very own Green Car Advisor, John O'Dell, brought to our attention the proliferation of detached, lead, wheel weights in our land fills, storm drains, and the environment in general. According to the EPA, approximately 50-million pounds of lead is used annually to produce tire weights worldwide in autos and light trucks. Wheel weights are the greatest unregulated source of new lead in our in our environment, according to Jeff Gearhart, director of the Clean Car Campaign at the Michigan-based Ecology Center.
Mercedes-Benz added some fashion to its wheels by using a common technique to reduce the amount of weight that's needed to properly balance a wheel, especially with the tire-pressure monitoring system (TPMS) the government now mandates. Those TPMS transponders weigh something, and casting an appropriately heavy chunk of metal opposite the sensor is a logical solution.
Here are three parts of a Mercedes-Benz TPMS: valve-stem/sensor, receiver (white box), and wheel-well initiator:
Seems like a good idea to us.
Chris Walton, Chief Road Test Editor @ 20,416 miles
hondacura4 says:
11:22 AM, 01/ 5/09
Makes sense and without these AMG alloys the C looks quite naked. Ill take a C300 6MT Sport w/AMG 18s in white/black please. Handsome car!
joefrompa says:
11:29 AM, 01/ 5/09
I've seen non-lead-looking wheel weights available for quite some time, in both original "pound on the lip of the wheel" and new "look at me I stick to the inside of the wheel" format.
Why is lead still used?
Also, wouldn't bullet manufacturing/firing be the biggest source of lead introduced to the environment? Maybe gun-ranges control the lead better than I know about, but I feel alot more lead is fired (both in solid and in dust-like format) from a gun than attached and falling off a car, on a yearly basis.
Joe