I had a grind-scrape at the rear axle also. Turned out to be a bad rear wheel bearing. I should be changing it shortly. Might want to check your rear wheels for binding or excessive free-play.

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Denis

1979 300TD 189,000 Miles, now running WVO with a home-made 2 tank conversion
1974 230 Gasser 189,000 Miles, For Sale
1961 VW Microbus 162,000 Miles
1961 Ford Fairlane 500, 53,900 original miles
1951 Oliver Super 55 Tractor
2002 Chocolate Lab