Reliability of coaches using DEF

[midasman]

I have wanted to upgrade as my Holiday Ambassador is moving toward it's 10th year. How are people doing with the newer coaches using DEF? It's made me wonder if moving back to a gas coach makes more sense. Or, keeping and modernizing my diesel pusher. We do Ouray, Colorado every year which means pulling my Jeep Wrangler over the Million Dollar Highway, climbing higher than 12000 feet...

[Mr_Mark1]

Midasman, you have legitimate concerns. As with anything in life that has a motor, it can fail or any of it's components.

Our DPF Monaco Dynasty gave us no trouble in the emission dept. We drove it almost 70,000 miles in 7.5 yrs.

We now have a little over 11,000 miles on our new coach. So far, no problems in the emission dept.

Sure, something can happen, I don't lose sleep over things I cannot control.

Safe travels,
MM.

[midasman]

I guess my concerns have been:
1. Electronic glitches even if the other equipment is operational
2. Half way to Colorado, or climbing the Million Dollar Highway and HELLO Limp Home Mode
3. Mr. Cummins dealer says "Hey buddy, you need a $15,000 DPF replacement
4. Or worse yet, the dealer tells you "Uh, we're just not sure what is wrong...
Remember, my concerns have arisen due to the dealer's inability to repair a long haul Dodge Cummins diesel with very great loss of ability to generate REVENUE...
I must, however, acknowledge that unexpectedly, no one with a new rig has come forward with campfire HORROR stories about emission nightmares.
??????????

[JumboJet]

Dtank wrote:
Awww - he just wanted to stir the pot or elicit responses.

Of course he knows better.......I think...:W

.

The diesel will go into limp mode under a few conditions - DEF fluid depleted and all warnings ignored. DPF full and no way to purge. Probably a few other items - maybe water in fuel.

[Dtank]

Mr.Mark wrote:

wildmanbaker wrote:
O.K.

What are you two wanting? In both cases, something needed to be removed from the fuel in order for the clean-up to work, on a extended basis. Gas, was lead, diesel, was sulfur. Problems, gas, valve seats and valves did not like the anti-knock replacement for lead, which is also poisoning our ground water, which the oil companies tried to tell them, but oh well. Problems diesel, removal of sulfur, which caused leaks and some loss of performance/mileage. The fix, different material for seals/gaskets in the fuel system. These are the facts that I know/experienced, if you do not like them, I sorry. Just like the "Laws of Physics", I cannot change them. If you do not agree, fine, unless you subscribe to the theory of if you repeat an old wives tale enough, it becomes fact.

I see you are stuck in the past. We are talking about regen of the exhaust. The NEW systems added to the current production diesel engines since 2007.

You said that 'regen' would effect hill climbing. Did you just pick that our of the air?

MM.

Awww - he just wanted to stir the pot or elicit responses.

Of course he knows better.......I think...:W

.

[Mr_Mark1]

wildmanbaker wrote:
O.K.

What are you two wanting? In both cases, something needed to be removed from the fuel in order for the clean-up to work, on a extended basis. Gas, was lead, diesel, was sulfur. Problems, gas, valve seats and valves did not like the anti-knock replacement for lead, which is also poisoning our ground water, which the oil companies tried to tell them, but oh well. Problems diesel, removal of sulfur, which caused leaks and some loss of performance/mileage. The fix, different material for seals/gaskets in the fuel system. These are the facts that I know/experienced, if you do not like them, I sorry. Just like the "Laws of Physics", I cannot change them. If you do not agree, fine, unless you subscribe to the theory of if you repeat an old wives tale enough, it becomes fact.

I see you are stuck in the past. We are talking about regen of the exhaust. The NEW systems added to the current production diesel engines since 2007.

You said that 'regen' would effect hill climbing. Did you just pick that our of the air?

MM.

[wildmanbaker]

O.K.

What are you two wanting? In both cases, something needed to be removed from the fuel in order for the clean-up to work, on a extended basis. Gas, was lead, diesel, was sulfur. Problems, gas, valve seats and valves did not like the anti-knock replacement for lead, which is also poisoning our ground water, which the oil companies tried to tell them, but oh well. Problems diesel, removal of sulfur, which caused leaks and some loss of performance/mileage. The fix, different material for seals/gaskets in the fuel system. These are the facts that I know/experienced, if you do not like them, I sorry. Just like the "Laws of Physics", I cannot change them. If you do not agree, fine, unless you subscribe to the theory of if you repeat an old wives tale enough, it becomes fact.

[Mr_Mark1]

Tyoungs... maybe Wildmanbaker will respond to us.

MM.

[DSDP_Don]

"tyoungs".....your comparison made perfect sense and was probably the best example that could be given!

[tyoungs]

Mr.Mark wrote:
Tyoungs, I was responding to Wildmanbaker. I understand what you are saying.

MM.

I was responding to Wildmanbaker also, guess I should have "quoted" his post - did not mean to point my response at you, just responding in the string

[moisheh]

Although RV'rs do not have much trouble with DPF's and DEF I would never use the hundreds of thousands of OTR trucks as an example. They have lots of problems. Big fleets buy say 1300 trucks when they need 1000. That is the only way they can have 1000 running trucks. The other 300 are either waiting for parts or sitting until the mfrs. find a fix. Even users of Sprinter diesels have troubles. The only reason MH owners do not have troubles is that we do not drive very many miles. remember that OTR trucks do at least 150,000 miles a year. That would be 25 years for a MH. Maybe in 10 years the mfrs. will have things fixed.

Moisheh

[Mr_Mark1]

Tyoungs, I was responding to Wildmanbaker. I understand what you are saying.

MM.

[tyoungs]

Mr.Mark wrote:

wildmanbaker wrote:

tyoungs wrote:
In general, when you can do the clean-up after the combustion process, then you can run the combustion for best efficiency and not lowest emissions. If you remember back in 1975, that was the first use of catalytic converters on gas engine vehicles. Everyone bemoaned having to use unleaded fuel but the 1975 vehicles with converters ran so much better and with such better fuel economy (because the converter cleaned up the exhaust "after" the combustion process)as compared to 73 and 74 that most people soon stopped complaining about having to use unleaded fuel.

Same with DEF, it allows the clean up to be done after the combustion process and with the advent of the digital controlled diesel injection, the engineers have much more control over every point of the combustion cycle. They can tune the combustion event for better efficiency and allow the clean up to happen in the exhaust after treatment devices. Lowest emissions in the combustion cycle and maximum efficiency in each cycle are usually not the same point.
If you have to "tune" the combustion process for lowest emissions with no after treatment, you generally are not at the point where you have max efficiency.

Not a very good comparison, unleaded gas to DEF. DEF does not harm the engine, unleaded gas was a BIG learning curve for auto manufactures. No one has mentions what happens when the engine control decides to go into re-gen, in the middle of a steep climb.

OK, what happens when it goes into regen on a steep climb?

We had the 2008 Dynasty for 7.5 yrs. and it would regen about once every 9,000-10,000 miles. Never noticed anything was going on unless I looked down to see the symbol lit.

We just went through our first regen on the new coach (11,000 miles). A message came up in the instrument cluster to let me know a regeneration was activated. Never noticed any difference in performance.

But, it never happened to us on a steep climb in either coach.

So, tell us what happens?

MM.

The point I was trying to make comparing unleaded fuel and catalytic converters on gas jobs, and DEF with Diesels is that both allowed the clean-up of the emissions to happen in a device after the combustion chamber. That in turn allowed the folks calibrating the engine to optimize the combustion process for power/torque/economy and not have to bugger up the combustion process to minimize emissions.

True that there was some learning curve with unleaded fuel (hardened valve seats and such) but that fuel allowed the use of the catalytic converter to do the major clean-up of HC and CO emissions. The side benefit was much longer life for spark plugs since you were no longer fouling them with lead.
Same thing with DEF, it lets you use an aftertreatment device to reduce emissions and the engine calibrators don't have to do all the clean up in the combustion cycle.

[wildmanbaker]

Oh, I guess I didn't answer the question. In limp mode, the ECM reduces engine power, and some times speed, until the regen is competed.

[wildmanbaker]

Well, most if the time, nothing. The regen is for the Diesel Particulate Filter. I'll admit, I have not messed with an RV with the new clean air requirements (2010 and later). Other diesels, usually have a 2 or 3 position regen switch for controlling the regen cycle. What this does is raise the temp of the DPF to burn the soot into ash by injecting fuel into the exhaust system. This happens more at colder temperatures, with extended idling. What happens if you plug the filter, or overheat the cat., contact your local repair shop for prices.