CRANKCASE doesn't really care about MEGATRON; he just joined the DECPETICONS because he was in a bad mood, and it's prety much lasted. As far as he's concerned, everything is pointless and stupid. He sees no reasonw hy anyone else should be enjoying things when he's so miserable. That's why he spends his time grumpily ruining things for AUTOBOTS and DECEPTICONS alike. He's not much of a warrior, so he specializes in just being inconvenient. His blaster arm causes metal to rust instantly.
Crankcase appeared in the following 4 comic books: