Technical advances in diesel engines and drivelines.

[dobroman]

New to forum. Maybe old timers or an RV mechanic can answer this.
My wife and I are looking to buy a used class A pusher. Question is, are the newer diesel engines and transmissions (2010 and up) substantially more advanced, technologically, than early (2000 to 2010) rigs?

[mci7]

Progress is good, being from the older days, never liked the computer age anything BUT I have learned the new way ain't so bad. My ISM500 runs great for 112,000 miles so far, uses no oil at all and gets nearly 9 mpg depending on how its driven.
The new DEF engines can go way up HP wise due to the lack of emissions due to the DEF sprayed into the muffler , so the HP can be turned up a lot and still satisfy the EPA.

Do not for get back in 1925 Rolls Royce was the greatest engine ever cause it could go 25,000 miles before needing rebuilt.

We came a long way baby.:)
Dave M

[Exracer2]

JimM68 wrote:
Wow..... you old guys sure do hate progress?
The original cummins ISL was what, 300 hp?
My 2008 DPF engine is 360...
A new one, with DEF, is what, 425 now?

So much for power...

I'm no fan of the government.... or the EPA, but really...

Just to use cars as an example, my Jeep wrangler is 14 years old. It has a multiport injected ODBll versionos AMC's venerable 4.0 liter inline six...
It has 279,400 miles on it.
It requires zero maintenance (Ichange the dino oil and filter every 10k just to make myself feel good, that 4-0 don't care) It uses zero oil between changes. It runs like a top, always...





Iremember cars from the "good old days"...
They ate spark plugs every 10,000 miles...
got 10mpg or worse.
Pinged like the devil if you got a load of bad gas...
And rusted to dust before they were ten years old...

Wow old guys? I thought 50 was the new 30! You young guys wish you had as good as us old guys back when they made real diesels! Lol

[dobroman]

Thanks all. Really good info here. No doubt that advances in gasoline engine technology has been worth it. Better mileage, hardly ever have to have a tuneup, change oil every 3 to 6k and they last and last. I've used diesel equipment on the farm when I was a kid. Fifty years ago. Always hated the smoke and stench. I was told that the newer diesels didn't smoke or stink. Since my wife and I plan on going full time next year, I thought I'd better get all the info I could before we went looking for a rig. I worried, that if we bought a decade old rig that we would really miss out on some great advances. Leaving the "clean air" debate for another time, I think an earlier rig is what we need. And, it's gonna have to last until were hang up the keys. Thanks again. I'm feeling much more informed.

[cwdavis]

Went to a Cummins engine seminar at the spring FMCA convention in Perry thinking we might learn something useful; problem is, the presentation started with ISC and what we learned, or re-learned, is that most 'progress' in engine design since the mid-1990s have been made to offset increasingly rigorous emissions standards.

As much as we love our all mechanical, low maintenance Cummins, though, we are not against the progress that has been made -- in the long run, we will all be better off with the current crop of lower emitting diesels!

So in answer to the original post, it may hard matter which model year is chosen for a used diesel Class A, so long as the coach is is good shape and floor plan favorable. One is not penalized for buying an older coach from a performance point of view, at least from the '90s onward. In fact, when our chassis suspension assessed at Perry, the mechanic driving the coach was really impressed with its power and handling.

[xctraveler]

The answer to op is yes there have been significant changes in diesel engines (gas too) over the last decade. Some are for the better and some may be problematic. I am not a tech or particularly biased user. I own my first diesel pusher, Cummins isc 2012 with def. From the pov of a fulltimer who runs maybe 15k miles a year I expect the engine to outlive me. It is quiet, the loudest noise is the radiator fan. It doesn't stink. It is 50% more fuel efficient than my 2004 gasser. Dang about every 3 months or so I need to put some def in the tank. At 2.79/gal (at the pump) it may cost me a penny a mile or 2, less if I stay out of cities and out on the open road.

The benefit to the environment of the epa requirements cannot be denied. I don't worry about it for me, I'm over 70, but I have 5 grandsons and I'd like them to be able to breath clean air. Not to mention their children. Loving the old ways may feel good, but it is pretty selfish. Leaded gas spread lead through the atmosphere and reduced the iq of everyone. It's gone thanks to got regulation. End of rant!

[jplante4]

Yeah, I think it's less about progress than it is about the gummint forcing change. RVers are free spirits and really don't like to be told what they should doing.

[JimM68]

Wow..... you old guys sure do hate progress?
The original cummins ISL was what, 300 hp?
My 2008 DPF engine is 360...
A new one, with DEF, is what, 425 now?

So much for power...

I'm no fan of the government.... or the EPA, but really...

Just to use cars as an example, my Jeep wrangler is 14 years old. It has a multiport injected ODBll versionos AMC's venerable 4.0 liter inline six...
It has 279,400 miles on it.
It requires zero maintenance (Ichange the dino oil and filter every 10k just to make myself feel good, that 4-0 don't care) It uses zero oil between changes. It runs like a top, always...

Iremember cars from the "good old days"...
They ate spark plugs every 10,000 miles...
got 10mpg or worse.
Pinged like the devil if you got a load of bad gas...
And rusted to dust before they were ten years old...

[Pogoil]

Exracer2 wrote:
I have been a diesel mechanic for 30 years. I have 2 cummins 12 valve trucks and a 1998 cat in my m/h. The most repairs that are made now days are fuel systems and exhaust . I will never buy one of these new diesels because of the cost to repair them and the lack of reliability. Gone is the million mile reliability of the diesel. The engine might last but at what cost to the remainder of the rest of fuel systems and exhaust? There are just so many sensors and computers on these things that just won't go that long anymore. Also the amount of labor to trouble shoot and repair is just crazy. Our main tool now days is a computer to plug in to the truck before when can do anything to them. I truly hate it. I will just keep my old reliable stuff going till I can't drive it anymore. Exracer2

I was waiting for a mechanic to chime in.

I have to agree, right now trying to help my son sort out an idle problem on a newer gas pickup way to many sensors to sort out very time consuming.

That said I hope my 1995 12 valve mechanical Cummins 8.3 in the motor home runs forever.

Pogoil.

[Exracer2]

I have been a diesel mechanic for 30 years. I have 2 cummins 12 valve trucks and a 1998 cat in my m/h. The most repairs that are made now days are fuel systems and exhaust . I will never buy one of these new diesels because of the cost to repair them and the lack of reliability. Gone is the million mile reliability of the diesel. The engine might last but at what cost to the remainder of the rest of fuel systems and exhaust? There are just so many sensors and computers on these things that just won't go that long anymore. Also the amount of labor to trouble shoot and repair is just crazy. Our main tool now days is a computer to plug in to the truck before when can do anything to them. I truly hate it. I will just keep my old reliable stuff going till I can't drive it anymore. Exracer2

[John_S_]

A 2012 cummins will run regular about 210 degrees in my cummins pickup. In my coach we run at 180. Both are normal but one is hotter then the other and in rear radiator coaches the issue then is cooling and the extra space needed for the radiator. The new Foretravels have much bigger radiators now then a few years ago on the same engine. Also I bet your 450 horse us an ISL not a heavy duty ism or ISX.

[Ivylog]

The Cummins wrist pin problem is for the ISL #46543077 - 46603939 for the 2005- 2006 years. Guess you could try and negotiate a lower price on a MH with one of those engines but by now it would have failed if it was going to IMHO.
The average DP use/year is 5-8K miles and at 10 years I'm at 68K miles. I plan on keeping my 04 Dynasty for another 10-15 years and doubt I'll have any major drive train expense... OK tires but I got 10 years out of the first set and with care and careful inspection plan to do that again.
From my reading the engines using DEF appear to get slightly better fuel mileage but when you add the cost of the DEF it appears to be a wash.

[two-niner]

First of all, the DEF is a red herring. It's usage is very little.
Second, we have a 2012 Tour with a Cummins 450hp engine (heavy & tag), has never run "HOT" in the past two years. And we cross the Rocky Mountains (going & coming) 95% of the time. At various rallies I have asked other owners about the heat gauge not going over the middle mark and they say theirs doesn't do it either. So I believe the running hot, from my personal experience is a non-issue.
Our last 6 month trip, out west (mountains) we averaged 8.4 mpg over 5,800 miles as measured at the pump. Our 08 Tour 40', no tag, with a particulate filter did about the same after about 10,000 miles.
I do agree every time the EPA makes changes, the engines and owners suffer.

Kerry

[moisheh]

If this were a forum for OTR trucks then the answer would be: Do not buy any truck after 2002. But we are driving RV's that do not get a lot of miles. There have been next to zero problems with 2007 to 2010 engines in MH's. This would be those with a DPF. The 2010 and up have the DPF and SCR. Idling one of those newer units will result in expensive problems. Eventually the mfrs. will solve the problems. The EPA forced them to use technology that is not reliable. I have seen comments from industry leaders that it could take 10 years to fix the problems. There is a reason that large fleets ( Werner, Swift,etc.) buy about 30% more tractors than they actually need. This is the only way they can keep units on the road. BTW:2002 was the last year with next to no pollution controls. In 2003 EGR became standard and that too can be problematic. Truck mfrs. are doing big volumes selling complete trucks called Gliders. This is a new body and chassis with a rebuilt pre emission engine and the rest of the drivetrain. Slightly cheaper than a new truck and no headaches. However those trucks cannot enter California and soon the EPA will prohibit the mfrs. from selling these kits. If only we could arder a new MH with say a DD60 from 02 !!! On the bright side the new engines are very fuel efficient and the air coming out of the exhaust is cleaner than he air going in!

Moisheh

[John_S_]

The first generation of particulate filters had issues. Still do in places. Buddy set his field on fire when his pickup decided to regen in the field as he was delivering hay. Def seems to be pretty trouble free but it is an added issue. The big issue is that from 06 to 12 we have had constant change. Engines run hotter now and that remains to be seen what the outcome is. My 01 cummins runs at 180 my 12 runs at 210.