Diesel motor home engines

Looking at older motor homes- I want to pull a car trailer with old car or tractor, Ma wants to pull a horse trailer with a horse or 2. I know the 454 or 460 car engines won't do it, V10 would be marginal, so looking at diesel "pushers". Most have Cummins, either 5.9 liter turned up to 300 HP, or 8.3 liter. Would the 5.9 be adequate for what I'm going to do with it? I don't want to pull the guts out of an engine that isn't up to the job.

My first thought is, 1. your not going to be pulling all that much weight. 2. I would think the the rear gear ratio would be something to look at. The rear ratio is probably matched to the engine whatever engine is in it. I had a single axle Mack dump truck with a 11.1 liter diesel engine, it had a 5 speed transmission and a 3.91 rear. It pulled very strong. Then I had a single axle freightliner dump truck with a 7.2 cat engine, automatic transmission and a 5.28 rear. It didn't pull as good as the mack but it did the job.

An engineer where son worked lost his wife and decided to retire. He bought a new motor home with rear Diesel engine and a lot of fancy accessories. Drove the new motor home from CA to
FL; He hated that motor home so much that he took a big loss, sold the motor home in FL and flew back to CA.

Not knowing anything about motor homes, but owning both of those Cummins engines, I would guess the 5.9 would be OK for short runs. For cross country/high speed hauls, or hilly going, I would want the bigger engine.

Cousin Eddie has a 40 ft diesel pusher. Cummins 325 hp turbo Monoco 6 speed auto. Needs more go going up mountains and not pulling anything.

Unless you already have a motor home. Go check them out. See if you even like them. I have worked on many that had new owners. That were proud of the new toy. Six months later it was up for sale.Know one couple that got a divorce over one.

Your old friend Bill needed to make many trips over Wolf Creek Pass pulling 32 foot goose neck with older tractors, heavy old tractors. Power was Ford 460 automatic with mid 3 00 ratio. First trip made the pull in low with engine hot at the summit, and me sweating cost of possibly transmission rebuild. Located an older Browning Lite ( later bought out by spicier) having st ratio and a 15 percent reduction as well as a 2 to one reduction . These aux boxes were often new in 2 ton dodge and IH single trucks. First return trip stopped at west end of Wolf Creek shifted aux box to lowest ratio. In drive gear speed odometer was showing 60 while actual was 30 mph. Just waved at large motor homes stopped to let their rig cool down. On the down slop shifted to 15 percent with truck in low very little braking required. Instillation dropped out barrier bearing ( truck was extended cab long box). Later when pulling 40 foot fifth wheel camper often in wind the 15 percent reduction gave better fuel mileage and less strain on truck. Large motor homes with diesel might require aux box from larger road tractor.

I've owned motorhomes and traveled this great country nearly 40 years especially the National Parks (Americas Best Idea) and love them and wouldn't be without mine. Sure the Cummins 5.9 will pull the load you mentioned, but if I were buying a Cummins powered large Diesel Pusher, Id opt for the 8.3. Tow packages and heavy rear springs and shocks or air bags or air shocks are something to consider for heavy towing. I've had good luck with big block gas engines in smaller Class C's such as the 454 Chevy or in the old days the 413 or 440 Dodge or darn 460 Fords, but haven't yet used the SMALLER 6.8 V 10 Ford.

Your money your choice (NOT ours) do as you please

John T

I've never owned a motor home and I have no intentions of ever doing so. (I keep thinking about all of the motel bills I could pay with the same money and without all the hassle).

However, from what I've heard, I would guess a motor home is powered for pulling itself and not intended to be a major tow vehicle. The whole idea might not be all that great.

I would go with the largest engine you can afford. You are basically pushing a "brick" down the road,not very aerodynamic,plus you are adding a 5-7000# load behind it. A marginal engine will suck fuel,tend to overheat, and basically be pulling it's guts out,especially if you get into hills pulling a trailer. Try to find one with good maintenance records. Too many around that haven't been serviced properly,run hard and put away wet. They aren't cheap to own,7-10 mpg,$250 tires x6, $200+ oil changes,plus generator maintenance. Also bear in mind,you just don't turn in anywhere with one pulling a trailer,it literally takes 2 acres to turn around, it's easy to pull into a place where you can't turn around and have to back out.....

J T is on the right track. A gas engine is going to be as good at pulling as the diesel but that is not the main concern here. The motorhome tranny is designed for the home only unless the original owner had it made to haul something heavy like a box trailer. You should also check out the braking system to see if it can handle all of the weight that you might be hauling.

I was looking at ads for motorhomes and I see that some have 3116 Cat engines and the later computer controlled 3126. I wonder how these work out.

(quoted from post at 00:59:02 06/11/16) Looking at older motor homes- I want to pull a car trailer with old car or tractor, Ma wants to pull a horse trailer with a horse or 2. I know the 454 or 460 car engines won't do it, V10 would be marginal, so looking at diesel "pushers". Most have Cummins, either 5.9 liter turned up to 300 HP, or 8.3 liter. Would the 5.9 be adequate for what I'm going to do with it? I don't want to pull the guts out of an engine that isn't up to the job.

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Actually, a motor home with a 454, or an 8.1 (496) will be more than capable of doing what you propose. The real issue will present itself when it's time to refuel. The majority of gas stations will accomodate cars and pickup trucks quite easily at the gasoline pumps, but are NOT arranged to accomodate a motor home with a trailer behind. The same rig, equipped with a diesel engine, can very easily be refueled at ANY truck stop.

As far as WHICH diesel engine to go for? The biggest, most powerful one you can find. You'll never regret it.

Your not pulling that heavy of a load that ether one of those engines with the right gearing would do the job with no problems.

EXACTLY, Braking capacity, Transmission Torque rating, and Transmission Cooling ARE EXTREMELY IMPORTANT FOR TOWING. That being said, the larger Class A bus frame diesel pusher motorhomes, especially with the 8.3 Cummins, are likely already well equipped to tow what the poster is asking about. If I were the poster looking for Motorhome tow capacity opinions and advice, I don't think Id rely too much on people who have never owned one or don't like them lol

Take care

John T

Rusty, "The real issue will present itself when it's time to refuel. The majority of gas stations will accomodate cars and pickup trucks quite easily at the gasoline pumps, but are NOT arranged to accomodate a motor home with a trailer behind."

OHHHHHHHH SOOOOOOOOOOOOOO TRUE

For years behind motorhomes Ive towed boats, trailers with tractor on board, cars, golf cart trailers AND WORST OF ALL DOUBLE TOWED a Car which had a Golf Cart Trailer behind it lol I GAVE THAT UP LONG AGO, not safe and usually not legal although I NEVER had any problems whatsoever whewwwwwwwww NEVER AGAIN.

When you are considering a fuel stop, you reallyyyyyyyyyyyy look carefully before pulling in to see if you can turn and get in and back out and not block traffic. Flying J and Pilot and Loves Truck Stops are our usual stop.

Best wishes

John T

My wife and I had a 37 ft motor home with a 8.3 Cummins which we pulled a 20 ft enclosed trailer with 3-4000 lbs, I could not tell the trailer was back there until you needed to park. It pulled hills better than being pulled by a Ford excursion with 7.3.

Run! Fast and don't look back!!

That 454 Chevy gas will easily do whay you are talking about Friend had one 44' with tandam rear axles one dual one single wheel and pulled a heavy trailer with tractors all the time with no problems. Never fixed the second gas tank either. Got rid of it only after it went floating in the air during a tornado with him inside, other friend was traped in his pickup from the storm. They were lucky for a flat tire on a trailer on the trip as if it would not have been for that tire they would have been parked at the spot the person was killed at in the storm. It was only after riding out the storm with no visuable dammage to the home did they find out that standing up on end made leaks in body they could not get fixed that he traded it off and is on his second one since and I believe they all have been gas. And his daily driver is always a diesel pickups and since I have known him he has had a 84 Ford, 86 Ford, 99 Dodge and just got a 01 dodge. Pulled same load with any of the motor homes that he did with the pickups. And I am sure some of you will rember the tornado that wiped out the fairgrounds the set up day befor the show. Ohio.

Have a 36 foot monaco with an 8.3 set at 300 hp.... and while it has a lot of power, the pump setting limiting it to 300 hp means that it will barely run 75 mph.... just NOt enough fuel to engine. I can pull with it but again,, top speed and power is limited by the pump setting.... and with a 27000 lb house going down the road, your power is very limited... Good news is,, that if I drive 65mph, I get 10.7 mpg... which is very good... if I run it wide open at 75 mph,,, I get 8mpg.... I when I say 75 mph,, thats only on flats and down hill..


Other models with the hp setting at 350 or 400hp, do much better towing and driving, but they also get 6 to 8 mpg at best...

We are on our second 1999 mh with both having the Cummins 8.3. The mh weighs 27000 lb an we pull a Chrysler van fully loaded with some stuff
such as a heavy power chair .I can assure you it will easly do 75 mph an more. Rarely on I75 between Ohio an Fl. will it need to shift.Our
first mh with 8.3 would clock 70 @2000 rpm however present one will clock 70 @ 1800 _+ . Both are very capable however present one does
accelerate some what slower.An as mentioned braking ccapacity of final rig you purchase is of utmost importance.An space to fuel is hands
down the winner over gasoline powered motor homes plus other advantages.

(quoted from post at 06:42:34 06/11/16) Rusty, "The real issue will present itself when it's time to refuel. The majority of gas stations will accomodate cars and pickup trucks quite easily at the gasoline pumps, but are NOT arranged to accomodate a motor home with a trailer behind."

OHHHHHHHH SOOOOOOOOOOOOOO TRUE

For years behind motorhomes Ive towed boats, trailers with tractor on board, cars, golf cart trailers AND WORST OF ALL DOUBLE TOWED a Car which had a Golf Cart Trailer behind it lol I GAVE THAT UP LONG AGO, not safe and usually not legal although I NEVER had any problems whatsoever whewwwwwwwww NEVER AGAIN.

When you are considering a fuel stop, you reallyyyyyyyyyyyy look carefully before pulling in to see if you can turn and get in and back out and not block traffic. Flying J and Pilot and Loves Truck Stops are our usual stop.

Best wishes

John T

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John, the same holds true for a 1 ton dually and 25' gooseneck trailer. You have to watch and pick your fuel stops.

Thanks to all for your input. We've had slide-in campers for 40+ years, so know we like RVs, but motor home idea is for a little more room to stretch out, but mainly for our kids and their families to use for their vacations. One family has 3 kids, the other 4, so its about impossible for them to (1) cram everybody in a pickup going down the road, and (2) have enough room in the camper when they get there.

It is a challenge to get engine information from RV sales people. They almost never know an engine model number- one said it was a Cummins, I asked which model, he said "Oh, there's more than one?"

Looking at one tomorrow with, supposedly, a 375 HP Cat. We shall see.

Goose:

Plus, most Motels have a swimming pool. Kind of hard to have a swimming pool in a Motor Home. lol

I can't help much, but you could try RV.net, they have a forum, for coaches, try over there. Lots of good info. Dan

Probably should avoid diesels new enough to have common rail injection, particulate filters or urea injection. .

When the kids were young we took a cross-country trip with a trailer. Solved the pool problem by getting a KOA Kampground book, and planned our stops at KOAs. They all have pools, and are generally very nice.

I think that will be avoided by staying away from diesels that cost very much. LOL

Currently working on a 32 foot pusher, with a 5.9 liter Cummins, for a lady. I haven't dug into the HP rating but, I drove it the other week, and in my opinion it's under powered. If you wanted to tow something I'd say it would be severely under powered.

On flat ground it took forever to get up to highway speed, even at 45. Once to speed it had no problem keeping it there on flat ground, but having driven larger and/or heavier vehicles, I can tell you for a fact it would have serious issues in hilly country, and especially in mountainous terrain.

Not to mention, pumping 300 HP out of a 5.9 is a good way to shorten it's effective life span. That's the very reason Dad and I looked at everything but Freightliners when looking for a cab and chassis for my service truck. Everything we heard about them related to the 5.9 Cummins and the problems they were having with them. Thankfully we found one with a Series 50 8.7 liter, Detroit as I love the truck's handling.

That's not to say the 5.9 is a bad engine, and it would be great in a smaller vehicle, but in a larger box, it's just not enough.

As far as the 3116, and 3126 CAT engines, I'd offer up the same advice on either of them. They are fine engines for lighter weight vehicles, but they wouldn't be enough for anything with any size.

Dad has a 3116 in his service truck, and it weights in around 19000 lbs. It's slow off the line, even on flat ground, but it's fine once up to speed. In the mountains, you'd be better off to get out and walk if your in a hurry to get to the top.

The really bad thing about either of the CAT engines, even the pre-electronic versions, is it takes over $3000 worth of special tooling to work on the top end (think changing injectors). As a result, your choices on mechanics for top end issues is going to be somewhat limited. Not necessarily a deal breaker, but definitely something to keep in mind.

One thing about a pickup vs a motor home: the motor home has a lot more space to fit a lot bigger radiator to keep the engine cool at a higher horsepower rating.

That's what's limiting the pick-up hp and tow ratings. Keeping it cool. The Isuzu duramax can accelerate faster with its max load than the Cummins or Frod, but it derates at the same load in a long pull due to heat. The Chevy/ GM trucks are supposedly getting a hood scoop to pull cool air into the intake for long pulls to help remedy this.