First of all, merci beaucoup for this awesome game from an IndustrialCraft/GregTech maniac!
I recently got the "Steamrolled" achievement after flattening my 10th spawner, but definitely not by running them all over. My base is developping quite slowly due to my goal "Lazy Bastard". so I'm quite sure i wasn't crushing so many spawners with my car...
Searching for "Steamrolled" in the Forums did not result in any mentions of this issue. Hopefully this helps!
[kovarex] Achievement "Steamrolled"
Re: [kovarex] Achievement "Steamrolled"
Thanks for the report, I fixed that for 0.13.6