I used shoe cream on my blue leather 83 300SD (came with the car). It does rub off, the trick is to burnish it with a soft cotton polishing cloth. You need to do few applications cause the burnising removes allot. Seems to have worked better when you let it dry for a couple hours. Kinda worked, but I think SEM or another product is the way to go.

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1999 E300DT (131,800) 154,000 Black on Black SOLD

2006 CLK 500 coupe Capri Blue on Grey (zoom,zoom)
47,000mi

04 VW TDI Passat 80,000mi
(Techno)

How to eliminate oil dependency through market-driven approaches.
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The Sound of Diesel Speed
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