If you are a new 1987 300D/TD owner, please read
this article... lots of information in there you'll want to know.
You need to verify the speedo with a GPS. Make sure the tires are proper size... 195/65/15 was factory, 205/60/15 is acceptable... anything larger diameter can cause the speedo to be off. You also have to check how far it's off at various speeds.... 25mph, 50mph, 75mph, 100mph (if you can safely do so). Mine are accurate within 1-2mph up to approx 100mph, yours should be the same. "Seat of the pants" does not count as a calibrated instrument, no matter how much you'd like to think so.
A vacuum pump for <$90 from eBay? I sure hope it was a Pierburg. If it's not... send it back and shell out the $300 for the Pierburg and be happy about it. You don't want a cheap Chinese pump to kerplode and do something like
this (which is highly unusual, regardless of pump brand). I would never, ever trust an offshore clone pump on an engine that costs $3k for a USED one ($8-$12k for a rebuilt long block). Not worth the risk!
