Yeah you got that right. I bought my 240D with a stopped Odometer. My 300SD was in great shape with 150K on the clock when I bought her but I soon found out the odometer was slipping at high speeds.
I got a good price on the car because I had a 3-4 flare on the trans. I got the car up to 200K before the trans gave up. But still, I would have paid less had I known it had 10-20% more miles as I estimated by GPS measurement vs. the readout.
The car actually looks better now. New Tex. Clean paint. New window rubber. It's actually shocking how many 123s and 126s on Craigslist have less than 200K after 35 years. They don't of course. Bad odometers on them all at one point or another. There's no way that any of these cars have made it this far on their first odometer. I've owned three of these things and everyone had goofy odometers.
And I took my car out on the highway today. I didn't have my GPS but I swear the odometer still slips a bit at speeds over 70. It's fine at 60. Goes one mile in a minute. But the odometer seems to slow down as I get over 70. That is, I should be doing 0.1 miles in less than six seconds but it takes ten seconds to do so. Like it still slips at high speeds. So I hay have another issue besides gears. My speedo reads correctly so it is hard to image what else is wrong.
Oh well, I will continue to investigate.