although it sounds like "the deathtrap carb" this is just accent. the words should be "deathtrap cab"
With steam engines there was a solid mass of steel in front of the drivers cab that would take a lot of any impact if there was a collision. A diesel cab being right at the front of the engine and built with only relatively flimsy metal would crush on impact along with the driver.
Hence "And the way things are as smashed there's bound to be They won't find very much of me"