I am 99% sure that on-road emissions lead off-road emissions, correct? If that is the case (correct me if I am wrong) if off-road engnes are transitioning to IT4, where are on-roads? Yes, I did ask this somewhere in the past couple three weeks to a month ago.

BUT - where I am going is if IT4 engines can be produced without urea, or DEF, in the off-road industry why can't on-roads do the same? Take a look at the new Deere IT4 engine. It has a DOC/DPF as before in T3, but it is a more efficient/cleaner engine - with no use of DEF.

I had a conversation with someone a little while ago that said if Deere had to be running entirely up to IT4 right now, with no extension of the time frame on T3's for the transition, they would be running DEF. The time and development (or, shall we say, "tweaking and experimenting"?) isn't there to slam-bang knock out production on IT4's without DEF.

Or is that the same catch that caught up with on-road production? Not enough research/development time to do the switch without DEF?

I know on-road and off-road useage is completely opposite of each other (for most scenarios). Off-road, when sized correctly (something we don't, and really can't do, with on-roads as the options aren't there) can run nearly entirely in it's prime operating range (ideal engine load vs. RPM). On-roads, especially lighter duty pickups, aren't always used, or can always be used, that effectively. The passive regens are great but even a heavily worked off-road engine is going to do active regens sometimes.

Thoughts? Comments? I would be curious what others have to say