Between-overhaul mileage of a well maintained RV gas engine?

[Geocritter]

I read about people getting huge between-overhaul mileages out of diesel engines, one fellow just wrote about getting 368,500 miles from a Cummins diesel and I’ve heard about truckers running diesels well over 500,000 miles. Some of this is to be expected since diesel fuel is also a cylinder wall lubricant, whereas gasoline is a detergent. Nonetheless, this leads to the question, what kind of between-overhaul mileage can one expect to get from a well-maintained large bore gasoline engine? Years ago, gasoline car engines wouldn’t go much over 100,000 miles without a major overhaul. My last 1998 V6 Caravan engine was still running great at 286,000 miles without ever having been overhauled. I realize that car usage is a lot different from truck and RV usage, but I still have to wonder what kind of between-overhaul mileage these large V8 and V10 RV engines are capable of, assuming that they’re well maintained.

Steve

[BillMFl]

Lets make this analogy. If you only got off your sofa once or twice a year your moving parts would not last very long. Run your engine until it reaches operating temps even when stored on a regular basis, and change oil and filters per manufacturer specs and your engine should enjoy a long healthy life. Sitting unused is no good for moving parts. Including both yours and the the MH.

[Mr__Jeff]

Recently sold my 1994 Southwind with over 200,000 miles on it. All original F460 engine. The new owner just returned from a 2,600 mile trip without worries of the drivetrain. According to Ford Fleet Services one should expect 400,000 miles from the F460 with proper care. This one is well on its way!

[Daveinet]

wolfe10 wrote:
I would differentiate between older vs newer engines.

The newer Vortec GM engines and Ford V10 engines will go at least 50% longer than the older engines they replace.

Or more specifically, GEN IV or higher block. Basically as soon as they came out with roller lifters (not that is the only difference).

Fireman-dan wrote:
yes the newer motors will last a lot longer. also the newer oils help get more out of a motor . even a older one will last longer .

I believe I would disagree with this statement. ZDDP is still the best anti-wear agent, and the newer oils have less of it. To compensate for this weakness newer engines have the cam pre-treated before it is installed in the engine. Newer engine also have more than double the size oil pans to compensate for the weaker additive concentration. This slows the depletion of the additives, more specifically ZDDP. If you are running an old engine, you should use an oil that still has the older quantities of ZDDP, or ad it to the oil.

To specifically answer the OP, someone eluded to the real answer in an earlier post, stating the biggest issue with an RV engine is how it is used. If the engine sits - especially in humid environments, it collects condensation inside the engine, which makes it rust. One is much better off to have an engine that is used regularly, that is unless it is stored in the southwest where the air is very dry.
We do talk about modern engines lasting much longer than older ones, but I do know of a guy who had an old Revcon, running a 455. At the time I talked to him, he had 275,000 miles on his gas engine, and had not done anything other than regular maintenance to it. It was still running strong. The issue was that it was maintained well, and was driven regularly. I would also say that it was probably not strained badly, as a Revcon is fairly light for its size.
I would say that unless you have been in control of the engine all of its life, the old standard of 100K for GEN VI and older/200K for GEN VI and newer applies in most situations.

[Flasho]

A gas engine can reasonably be expected to go 200,000 miles.

[okgc]

Million Mile RV hauling Silverado

I believe to many motorhomes just sit, if they are driven they will last many miles.

[Geocritter]

427435 wrote:

Actually, thinking about it a little more, the age of the engine (gas or diesel) may be the bigger issue. Rubber, electrical, and plastic parts get tired after 10-20 years.

I agree about the rubber and plastic parts. I learned a long time ago that whenever I did transmission work on a +100K mile vehicle it was a good idea to at the very least replace the rear engine seal while I had the transmission out. As far as valve seals go, they're pretty simple to replace without having to do a big-time engine teardown or cylinder head removal, so why not.
Steve

[rjstractor]

For the most part, the engine will outlast the house part, maybe except for full timers. I know a guy who spun a rod bearing in his 8.1 Workhorse at just 81,000 miles but that seems to be an anomoly. Many go 200,000+. The durability gap between gas engines and light duty diesels seems to have shrunk somewhat.

[427435]

With today's synthetic lubricants and good maintenance (including keeping the cooling system in good condition), there is no reason a V10 or 8.1 won't go 200,000 miles. At 7,500 miles per year, the house part will be falling apart first.

Actually, thinking about it a little more, the age of the engine (gas or diesel) may be the bigger issue. Rubber, electrical, and plastic parts get tired after 10-20 years.

[Geocritter]

I recently purchased a class A that has 58K on the odometer. Supposedly, but I don't have the records to prove it, the engine and trans were both replaced at 30K. Currently, my coach is a monument to deferred maintenance, so I can well imagine that the engine and trans had to be replaced based on the lack of maintenance I've seen throughout this rig. However, the 460 V8 engine runs very good and shifts very well with no lubricant leaks or other issues, so maybe the engine and trans actually have only 28K on them. My future plans are to explore North America in yearly 5,000 mile loops, staying mainly on interstate highways with the RV (I'll explore the back roads with my 25mpg Dodge Caravan and a small 60mpg motorcycle). I'm figuring that with mainly steady speed highway driving and sticking with Mobil 1 synthetic oil and an oil change interval of once a year or 5,000 miles, should be more than adequate for the type of usage I'll be subjecting the rig to. I'm hoping with the this maintenance schedule I can expect to get another 50K out of the engine before I have to start worrying about its future.

BTW the Dodge Caravan I sold with 286K had 151K on it when I bought it used. It hadn't been maintained well and the first thing I did was replace the noisy varnish encrusted valve lifters. Nonetheless, other than parts like timing belts and water pumps, the engine was literally trouble free for the 136K I owned it (using Mobil 1 synthetic oil and an 8K oil change interval). However, like I said, RV usage appears to be a much different thing, which is why I'm asking questions.

Steve

[Clay_L]

When the Chevy Vortec 8.1L engine came out they announced that it was designed to last 200,000 miles before overhaul.

[kaz442]

Had a fleet of ford 5.4 E-350 with 480,000-635,000 miles on them. Everyone org. Drive trains.
JKaz

[Dale_Traveling]

Geocritter wrote:
What kind of between-overhaul mileage can one expect to get from a well-maintained large bore gasoline engine?

It's becoming pretty rare to overhaul an RV engine or transmission. Once you start getting usage high enough to consider reworking the power train the costs involved may exceed the value of the coach. The question becomes one of economics.

Maintenance of the power train is only 1/2 the picture, usage is the other. If the coach is loaded to max GVWR and towing 5K Lbs. daily up and down I70 between Denver and Grand Junction then the expect life of the power train might be a bit less than average.

[Fireman-dan]

yes the newer motors will last a lot longer. also the newer oils help get more out of a motor . even a older one will last longer .

[wolfe10]

I would differentiate between older vs newer engines.

The newer Vortec GM engines and Ford V10 engines will go at least 50% longer than the older engines they replace.