0-60 should be in the 9 second range. I'd definitely rule out the oxygen sensors; if they were that far off they would set a code. Your gas mileage is good; I do well to get 20 highway but then I never ran a set of brake pads for 90K on anything. The rev limiter should be somewhat over 6,000 rpm; my ML sees 6 grand every week (118K and going strong). My hunch is that it's the MAF sensor, but there's got to be a way to prove it. Replacing parts on a hunch is very expensive. Seems to me if it's that low on power it should have set a code.

The stock rotors and Pagid pads work fine for me in all kinds of weather. I have never had the brakes hydroplane on the ML.

Last one's easy. I use Valvoline DOT 4 on the street and Wilwood DOT 3 on the track. Reason being, on the street you want the highest wet boiling point you can get, on the track dry boiling point is more important because you change the fluid every couple of weeks.

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Lenny

There are only three sports: bullfighting, motor racing and mountaineering; all the rest are merely games. --Ernest Hemingway

'10 GL550/'04 BMW 545/'99 BMW 323/'98 ML320/'87 VW GTI (race)