First you need similar code to the below in your unit. Then you need to go in and create a new fx in the fxlist.ini, you'll probably also have to go in and edit some particle systems. I havn't done too much with this...so sorry I'm not too much help
Code:
Behavior = SlowDeathBehavior ModuleTag_blitzexplode
DeathTypes = ALL -CRUSHED -SPLATTED
ProbabilityModifier = 100
DestructionDelay = 700
DestructionDelayVariance = 600
OCL = FINAL OCL_MedTank
FX = FINAL FX_BlitzGenericVehicleDieLarge ;FX_BlitzGenericVehicleDie
End