The dpf "scare" is history. It in itself is NOT problematic and I honestly think that too many folks put too much emphasis on deleting them, at least on smaller tractors like the standard L-01 series. Having worked in the field on hunderds of L01's for various issues, I've had TWO that needed the DPF cleaned, and both were victims of ignoring the lights, beeper, and power reduction. Flat out ignoring them 100%. Everyone else I spoke to said that the system works good once you figure it out. Seamlessly is what most have said.
Removing it doesn't solve the expense of the high pressure common rail fuel system parts failure. It only makes the owner feel all warm and fuzzy inside knowing that he can now roll coal like an old tractor.
If you want the dependability and "cheap" maintenance of the old tractors, by all means buy an older one. I personally think that's going to be a better option.
And no mention of the legalities of removal and/or tampering with them in such a way that takes away from their original operation and the liability that an owner takes into their own hands. To each his own. I've seen what happened to a medium sized company who supported oil field work-they had a fleet of 11 (as I recall) Ford 6.4's and deleted every one of them for mileage and maintenance concerns. It took no time for the highway police to nail them on a separate incident (speeding), then report it to the EPA, then guess who comes in for a spot check?
My question is how do the people that make the delete kits for tractors get away with the liability and legal issues of disabling/removing the DPF? On road cars/trucks, they generally have "for off highway use only" as their way of releasing their liability. But that doesn't work for tractors obviously.