Technical advances in diesel engines and drivelines.

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.

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

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

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.

Ivylog, you indeed did interpret my question correctly. And thanks to all for the advice. Although a seasoned mechanic, I've had no dealings with diesels. Most of your posts confirmed what I had suspected. With the longevity of diesels being what they are, I had hoped that buying a pre 2005 would not penalize us with less than optimum fuel mileage or power. Mr. Mark mentioned early 2000 Cummins wrist pin issues. Thanks for that. This is the kind of info I need before we give up our old 460 Ford class C.

I love my B5.9 uprated to 300 hp. It is 12 MPG at about 65. I stay pretty steady on all but the larger grades. My Allison MD3060 has ran flawlessly except for an ECU hiccup last summer. The old 12 valves are the king of the cummins small 6's and I have seen many built to over 1000 HP and about that much torque. There have for sure been many innovations over the years but I am not sure all the innovation was for the better. Common rail fuel injection did quiet them down but I did not see the fuel mileage increase with them. The so called advancements have added a great deal of cost along with in some cases lesser MPG. Any Diesel should get you into the 500,000 mile longevity range and beyond.

In all the 50 yrs I drove on the road I have never seen so many new trucks broken down on the side of the road because of some stoopid little computer part or fuse, slightly low water will shut them down where as the older engines would run forever down a gallon in water, electronic fuel pedal's another nightmare that I won't get into, Just give me an old manual controlled engine anyday, more power and better fuel consumption on most of them, it was very seldom you ever seen an old 220- 335 cummins broke down on the road and if it was it usually was fixed in a few minutes, not on the hook. Just my thought's.

OP, I interpreted "substantially more advanced, technologically" to mean improvement and IMHO the answer is still NO. Are the newer engine more complex... heck YES and more expensive. Has it been worth it??? only time will tell.
MM, I made sure my 04 Dynasty had a 03 engine in it as the 04 emission changes had not been in use long enough to know the results. Little did I know that the 04-06 bigger Cummins did not meet the new requirements but they were able to sell them by using credits from their 5.9 ISB engines that had a less restrictive emission standard. Cat not having any small diesel engines ended up paying a fine on engines they sold in those years. Now with a long track record the ISL and ISX engines have proven to be good with no ill results in those years so I was wrong to worry about it. I'm glad you did not have any problems out of your 'particulate filter' (the major change in 07) but as stated above I'll try to find one without it if I have to replace my 04. I do remember the smog in LA back in the 60s but doubt I'll ever be back in CA with my pre-emissions MH as I vote with my wallet.
Yes, I dislike the EPA as they have no idea what a cost/benefit ratio is.

You guys remind of the days when people would say "Don't buy a car with a catalytic converter"... Are you still driving a 1972 Ford LTD? LOL!

First, I respect Ivylog's, Executive's and John S.'s posts as we have all been here a long time.

But, don't scare the new guys away from new technology. Our 'particulate filter' Cummins has been fine with almost 70,000 miles and 7.5 yrs. of ownership. I've not heard of any major issues with these engines or even the DEF engines. Do they need repairs?, I'm sure some do as well as the older engines. Remember the wrist pin issues on the early 2000's Cummins?

I don't see the big 18 wheeler's piled up along the Interstate.

I think there is a horror story on everything on the Internet.

MM.

This time I AGREE with Ivylog....:B....his post is spot on IMHO.......Dennis