We have a 2000 SL2 it has less than 80K miles and is needing a third motor. 1st motor spun rod bearing and I haven't open this motor yet. it was a junk yard motor with 135k on it. I paid 700 for it. It was making the same noise so I'm thinking it's the same, (rod bearing).

My question is this. Are the motors prone to spinning the bearings?

And yes !! I do keep oil in my motors. I know that is the first question on everyone's mind. I'm a 40 y/o army mechanic( I know, that's doesn't say much) and have had over 50 cars in my life. not one of them have spun a bearing.

 

If there's been a lot of that going on (rod bearing issues)- it's not been mentioned here. I'm assuming you are past the "tire-melting" stage, and don't spend the weekends drifting around your town ... I'd be looking at simple bad luck. Happens sometimes ......