Victory Pete
Silver Member
Typographical error. IT3 should have been T3 (EPA Tier 3). IT4 is Interim Tier 4. Eventually IT4 will migrate to T4 (Tier 4). These are increasingly stringent limitations that the EPA has put on diesel emissions. Can't give many specifics, but generically the difference will likely be in the engine tuning, the addition of a DPF (diesel particulate filter), and possibly a catalyst. All new diesels between 50 and 750 hp are now IT4, under 50hp moves to IT4 in MY2014. T4 is the final and most stringent standard, but that's down the road a piece yet.
//greg//
I noticed for the IT4 the oil change schedule is reduced.
VP