As the tiers progressed there has been learning. Of course I see the remarks that the current emissions regs are the responsibility of the current administration while in truth they were set in 2004 with Republican controlled White House, Senate, and House of Representatives. Conclusion - people want clean air no matter what party. They do jot want the US to be another China with people wearing masks and traffic being shut down completely on the high pollution days. Black smoke out of the exhaust is carbon from unburied fuel. Wouldn't it be better to burn all the fuel making more efficient engines? Cars went through their learning cycle but today's cars eat the old timers alive when it comes to fuel economy and engine life. Jets used to leave a trail of smoke behind when they took off. They had to clean up their act. Cooled EGR, a big energy waster? When John Deere came out with it on their 8000 series tractors they set new standards for low fuel consumption per unit power meaning if you do your design work, you get your engine right. Several engine manufacturers are now selling their engines as meeting tier 4 final with no treatments, just efficient engine design. Are they right? Time will tell. I read articles saying defeating cooled EGR (plenty of kits for truck engines) will make your engine run cooler. It depends on which part of your engine. Exhaust gas is cooled by the engine coolant which is controlled by the thermostat. If the design is done right, coolant temperature will remain the thermostat temperature until you reach the limit of the cooling capability. The internal engine parts, however, see different temperatures which don't show up on any gauge. Increase the oxygen in the cylinder, more fuel can be burned and components sensitive to combustion chamber temperature like the valves and head gasket may fail earlier depending on the component design. When I worked for a Case we switched from Navistar to Case-Cummins (Consolidated Diesel Company) engines. The original design had a cast iron insert in the aluminum pistons to prevent the high combustion temperatures from eating away the top edge of the piston. Somebody's cost reduction idea was to eliminate this insert on combine engines because they don't see the steady high load of a tractor. They didn't ask the combine guys who knew the opposite was true. Cost Case $11 million dollars to replace the pistons on the affected engines, all to save $6 per piston. Same us true of all new engine designs - engineers think they can design a lower cost engine than the other guy and sometimes it blows up in their face. One major change on a lot of CUT's is a switch from indirect to direct injection. Indirect allowed lower injection pressures but is inefficient. Now most have the efficient direct injection, many with common rail injection systems which break up the fuel droplets allowing them to burn more efficiently. Less unburied fuel out of the exhaust. I looked at Kubota's engine specs and the new
L6060 engine is 20% more efficient than the
L5740 it replaces. Many companies are reducing engine cost by replacing 6 cylinder engines with 4s, 4 cylinder engines with 3's. Can I guarantee your Tier 4 engine won't have problems? No way - they are designed and built by humans who are flawed. Would I buy a Tier 4? In a heartbeat. I have an 2011
L5740 for which I expected top dollar based on people's statements here on TBN so I could sell mine at the premium price and get a
L6060 which Kubota would have to discount to move. Did it happen? Dream on. My
L5740 value has plunged because there is an upgraded model available and the
L6060 gets the same dealer discount I got on the
L5740. So if you really want an older
L5740 to get away from the DPF, I can sell you one 3 years old with only a little over 600 hours for the visit of a
L6060 and you won't have to worry about a DPF.
