I've been talking to alot of owners with the new engines and they are less then satisfied with their mileage. Is this true with most people??
Along with bad mileage there is a miraid of problems with maintaining the system. One fella replaced a thousand dollar part 3 times under warranty since 08.......
Also there is a problem when the truck decides to go into burn out mode which I have been told is necessary if there is too much soot or something built out in the system....During burn out mode truck's computer gives you acouple of minutes to get yours truck off the road before it shuts you down.......... Then it idles at high idle for 20 minutes to burn off the soot...........what if your on a major bridge!!!! geez
Is there truth to any of this?? Sounds like a major step backwards.

 

my boss has 2 09 T660's. 550 cats, 18 speed and 3.55 gears. he pulls race cars with them both all over the country. before that he was doing it for what we do (us. mail) a friend of mine driving one of them says that at 65mph it was barely getting 6.2mpg.

for comparison i know someone with a 03 379, 550 cat, 18 speed 3.36 rears and he says at 70 he can get about 6.

i've been thinking about this a lot lately... i'd be really looking in to a glider truck.

 

The EGR system is what causes the poor mileage and is also the reason the truck has to "regenerate".

Many trucks have had catalytic converters built in to the mufflers since the late 90's. They have caused many problems related to increased back pressure in the exhaust system because they plug from the soot of a diesel engine.

When they added the EGR system to the engines in 2006 the mileage dropped and the catalytic converters began plugging even faster. Anyone that's had to replace one of these mufflers with the catalytic converter inside knows that they cost nearly $2000.

I think it was in 2008 or 2009 they started putting the regeneration system on the trucks that forces the engine to run very rich so the exhaust gets very very hot to "burn" the soot from the catalytic converter which causes even worse mileage. If your traveling on the expressway when the regeneration is needed it will allow you to keep going but if the truck decides to enter the regeneration while your in town, you will have to sit and wait for it to complete. I have a friend that has a 2010 Pete that pulls belly dump locally. He frequently has to sit and wait sometimes for an hour and a half for the regeneration to complete. Some times it happens twice in a day. The truck has been to Cummins and Pete many many times and they can't seem to resolve the problem.

I would NEVER consider owning a truck with EGR or even a catalytic converter. I would go with a glider kit and an N14 if I needed something new. Even less expensive would be buying an older truck and going through it from top to bottom and then put it on the road. Unfortunately too many companies want to dictate how old your truck can be.

One of the things that surprises me is that the government always talks about the "carbon footprint" of things like power plants and manufacturing facilities but they don't look at trucks that way. The government mandates regarding emission controls on heavy trucks actually increases the carbon footprint of the trucks.

Hydrogen injection (aka:hydrogen boost) on a diesel truck would improve fuel mileage and power while greatly reducing overall emissions, all without EGR or catalytic converter. The process is simple but the government doesn't want to hear about it. More importantly, the government doesn't want YOU to hear about it.

 

Come on, Schnerdly, that's a truckstop lunch counter story if I've ever head one. You've got your facts all mixed up.

Fuel mileage does suffer with EGR and DPF. No getting around that. But the DPF will do its regeneration when it wishes, and you DON'T have to sit on the side of the road and wait for it to complete. An hour and a half? BS!!!

 

Shnerdly
Thanks for your very informative post. I found it strange more people aren't discussing this topic. This would explain why its so easy to sell a good quality older truck with a n-14 engine.

 

BS is not something I'm prone to Bandit102. In fact, I'm not even into idle chat. When I post, it's from experience relative to a specific question or problem.

This particular truck is one of ten in a fleet of identical Peterbuilts all purchased at the same time. It has spent as much time in the shop as it has on the road and neither Pete or Cummins has been able to resolve the problem with it in over 10 months.

The other 9 seem to do just fine as far as EGR engines and city work goes. By that I mean when they need to regenerate, it only takes them about 20-30 minutes and usually only happens once or twice per week. But even that is a pain in shorts when your being paid by the ton.

As far as the basics of EGR trucks that require regeneration, what I said is absolutely correct. If your on the expressway it probably wont be a problem but if your in town or not cruising for some reason, you WILL have to stop and wait for the regeneration to complete unless the company or truck owner has enabled the computer option for the driver to postpone the regeneration until a later time but you can not postpone it indefinitely.

 

ERG(exhaust gas recirculation) has nothing to do with the regeneration system.

 

Though the EGR system and regeneration of the catalytic converter are not directly linked in function, it was the introduction of the EGR system that required regeneration so actually, the EGR has everything to do with regeneration.

Because of the inefficient design of the internal combustion engine and the related fuel systems, the government decided that the EGR system should be developed to introduce exhaust gas back in to the engine in an attempt to re-burn more of the fuel that wasn't burned the first time around. The first problem with the EGR system is that it's a government mandate with no science behind it. The second problem is that when you reintroduce the exhaust to the engine, your reducing the amount of air going in to the engine causing it to require many other components to compensate, all of which provide the combined result of poor mileage and the need to regenerate a catalytic converter on a diesel engine to remove the resulting soot.

To get a truly cleaner burning engine you need to modify the fuel to burn more efficiently. This can be accomplished in a number of ways. Hydrogen boot causes the fuel to burn longer in the cylinder providing more complete combustion which translates to better mileage and improved performance. Another method would be to vaporize the fuel before introducing it to the engine. Fuel injection systems atomize the fuel which is better then carburetion by far but not nearly as good a vaporization. If you combine vaporization and hydrogen boost along with the proper tune of the engine you can get some very serious mileage improvements. In some cases a 50% improvement.

I worked on a project with my father-in-law back in the early 80's where we modified a Ford 3/4 ton 4WD pickup with a 400M engine, automatic transmission and 4:10 gears, to run on vaporized fuel. On a trip from Minnesota to Arkansas, we got a little over 26MPG. Prior to the modification the truck was lucky to get 14MPG. Thats almost a 100% improvement and we did that with a backyard system. Admittedly we had problems not the least of which was frequent backfire that eventually caught the carb on fire but we're not engineers so I wonder what would have happened if some automotive engineers tackled the project. We later learned that vaporized fuel burns faster then atomized fuel so we would have had to reduce the camshaft overlap to eliminate the backfires but that was beyond our capabilities. The same is true to run a vehicle on 100% hydrogen.

 

EGR's have been used in auto's since the 70's. It's been on trucks manufactured since late 2003. (cat "bridge" motors the exception) It's not a new technology. DPF has been required since late 2006. Most trucks use the burn-off method for the DPF,catalyst method requires frequent replacement of the filter. You can put an "add-on" DPF on a motor without an EGR(reefer unit upgrades are an example) Neither system is dependent on the other.

 

I am aware that EGR has been in use on gas engines since the 70's but that doesn't change the nature of the technology. A government mandate does not make the technology sound. With every cubic inch of exhaust gas that you introduce to the intake of the engine, that displaces a cubic inch of fresh air. Fresh air is REQUIRED for combustion. More precisely the oxygen in the fresh air is required but the exhaust being introduced to the engine displaces some of that air and is 100% counter productive to good combustion. That's why your mileage drops with the EGR system. When you reduce the MPG, you increase the carbon footprint of the engine. The EGR actually increases some of the undesirable gases in the exhaust such a carbon monoxide.

I didn't say they were dependent on each other. What I did say was:
Let me clarify. The EGR decreases MPG by displacing fresh air with counter productive exhaust gas thereby increasing the soot produced by the engine which is the only reason the catalytic converter needs to be "regenerated". Neither system is dependent on the other for their individual function but the EGR definitely has an effect on the catalytic converter.

No matter how you look at it, EGR is a flawed technology invented by a bureaucrat and mandated because that same bureaucrat has no concept of how an internal combustion engine works. The more efficient you make the engine the cleaner the exhaust will be. Whats the next mandate, using FOOD for fuel. Oh, wait, we're already doing that.