The tires on any four wheel drive vehicle need to be rotated about every 5,000 to 6,000 miles. Otherwise you will get the wear pattern you describe. Have them rotated now and you will have no problem. Leave them up front too long, and you will get cupping wear.

Our old 320 can go 300 miles on a tankful, about all my bladder can usually stand. My wife would have no problem in one of the old M-B diesels that goes like 700 miles!

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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)