tow vehicle for our Camplite 11 FK

[gogreen]

[quote source="/post/18160/thread" author="@billmoore" timestamp="1454107959"]

[font size="3"]Mathematically HP is force times distance divided by time. So, with some simplification, HP=Torque X RPM. If torque stays essentially constant over a short interval an engine can increase RPM and HP until it blows up. For this example the Pilot engine, rated 250HP @5700rpm would put out 276 HP @6300rpm (250*6300/5700). Can you hear the metal wearing?
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The problem with applying that formula is that manufacturers rate the horsepower at the peak of the horsepower curve. If you look at this dyno graph for a 2009 Pilot you can see this:


[img style="max-width:100%;" src="http://hondanews.com/media_storage/GIF/6_09Pilot_Pwrtrn3.gif"]

Horspower peaks at 250HP and rapidly drops off from there as RPMs approach redline.

For towing what really matters is the torque curve, not the horsepower curve. In that graph you can see that the Pilot has a pretty broad and flat torque curve (90% of peak torque at just off idle), which is very desirable for towing.



wow.... what did I start?.. I am a lowly Texas History/music education major. My brain hurts now! Went out and drove the Traverse and the Durango this evening and really liked both of them. The newer Durango really has some good giddy up and go. Going to have to go back tomorrow in the daylight and drive all of them next to each other and try to make a decision before I am too old to drive![/quote]

[djsamuel]

I know people that have the Durango, as well as the related Grand Cherokee, and love them.

[charliem]

[font size="3"]Either the Traverse or Durango should be fine for the 11FK, even with the 3.x liter engine. The AWD versions would be best, but my second choice would be the Durango because their two wheel drive version is rear wheel drive. The Traverse (and Pilot) is front wheel drive. For towing the rear wheel drive is preferable to front wheel drive. Of course if you could find an AWD 5.7L V8 Durango, but............  
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[david]

Charlie:

That is an interesting thought, that if you only have 2WD then for towing it is better if it is RWD. Some thoughts on a lazy Saturday morning:

FWD vehicles are almost always front heavy, but they are engineered for it. Adding weight in the trunk, or on the hitch will help to balance it out. RWD vehicles are often more balanced front to back. So it would seem that for balance a FWD vehicle might be better.

But climbing traction is a different story. Unless you always camp in city park like RV campgrounds, you will occasionally be in situations where you need to climb out of a steep back in campsite and will need lots of traction.

Our normal FWD, but with 4WD capability Pathfinder does sometimes spin its front wheels when climbing a grade of gravel while towing. There is less weight on the front wheels while climbing and that is when you need the weight for traction. So that is a problem if you only have 2WD. I shift into 4WD when that happens and climb right up. But if I only had RWD, I don't think I would have a problem climbing.

David

[charliem]

[quote source="/post/18182/thread" timestamp="1454174187" author="@david"]Charlie:

That is an interesting thought, that if you only have 2WD then for towing it is better if it is RWD. Some thoughts on a lazy Saturday morning:

FWD vehicles are almost always front heavy, but they are engineered for it. Adding weight in the trunk, or on the hitch will help to balance it out. RWD vehicles are often more balanced front to back. So it would seem that for balance a FWD vehicle might be better.

But climbing traction is a different story. Unless you always camp in city park like RV campgrounds, you will occasionally be in situations where you need to climb out of a steep back in campsite and will need lots of traction.

Our normal FWD, but with 4WD capability Pathfinder does sometimes spin its front wheels when climbing a grade of gravel while towing. There is less weight on the front wheels while climbing and that is when you need the weight for traction. So that is a problem if you only have 2WD. I shift into 4WD when that happens and climb right up. But if I only had RWD, I don't think I would have a problem climbing.

David[/quote][font size="3"]David,

As usual you're right and I really like the climbing argument. Your thoughts totally support my standard position that I will always own 4X4. Even on dry pavement I've dropped a wheel off the side of a campsite and popped into 4WD to get back up. AWD would do the same. Your thought on balance is valid, but consider that adding the trailer adds weight to the rear and subtracts weight from the front (driving) wheels. Unless you use extreme WDH [       ] you're taking weight off the traction wheels and putting it on the unpowered wheels with FWD.

Have a good lazy weekend.
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[hogtyd]

I pull my 13QBB with a '97 4Runner with only 183 HP and it does fine and averages 10 MPG. Above 60-65 MPH the wind resistance does make itself known, but I rarely have a need to exceed that speed regardless. So I think you'd be fine with the 11FK with any of those tow vehicle choices.

Graham

[daplumbr]

I think all the vehicles mentioned so far will tow the 11FK just fine. I think you're on the right track to take good long test drives in each to look at all the travel/use factors; safety, ergonomics, comfort, efficiency (when not towing), reliability, and dealer quality. After you've picked out a couple that you really like for the above reasons, let the deciding factor be the one with the greatest engine low-end torque! 

[gogreen]

Thanks for all the information. We finally have decided on the 2013 Nissan PF with the tow package and "tow mode" switch. Really like the ride and the room in it though I think the gold color may clash with our pretty yellow trailer. May have to paint one or the other...!

Looking forward to our next outing now!

[david]

Good choice!!

With regard to the tow mode switch, we don't bother with it on our 16TBS. Like I said before, with it off, we pull at about 2,300 rpm at 60 mph and get 13+ mpg. For comparison, with no trailer, the vehicle only revs to 1,700 at a steady 60 mph. So the CVT senses the increased load of the trailer and increases the ratio. Just as you would expect to happen.

I can't remember the numbers but I would expect that the tow mode would increase the rpm further at 60 mph. The higher rpm for the same speed will reduce the torque and therefore the engine stress, but since the trailer pulls nicely at 2,300 rpm and 60 mph, and seems to have plenty of additional torque at that point for acceleration, I think that we are fine pulling the 16TBS with the tow switch off.

Your trailer should be even easier to tow, but not much. Frontal area which is the same between your and my camper is more important than weight and rolling resistance at 60 mph.

David

[spot1]

[quote source="/post/18343/thread" author="@gogreen" timestamp="1454537788"]Thanks for all the information. We finally have decided on the 2013 Nissan PF with the tow package and "tow mode" switch. Really like the ride and the room in it though I think the gold color may clash with our pretty yellow trailer. May have to paint one or the other...!

Looking forward to our next outing now![/quote]Please keep us updated on your first outing with your "new to you" tow vehicle & CL 11 rig!

We like towing our Mighty 11 with a 2013 Nissan Frontier 4.0L crew cab pickup with Leer shell. Will eventually move up to a 5.7L Toyota Tundra to tow a Toy Hauler.

[charliem]

[quote timestamp="1454542087" author="@david" source="/post/18344/thread"]Good choice!!

With regard to the tow mode switch, we don't bother with it on our 16TBS. Like I said before, with it off, we pull at about 2,300 rpm at 60 mph and get 13+ mpg. For comparison, with no trailer, the vehicle only revs to 1,700 at a steady 60 mph. So the CVT senses the increased load of the trailer and increases the ratio. Just as you would expect to happen.

David[/quote][font size="3"]David,

With conventional transmissions the function of the tow/haul switch is to lock out the overdrive gears and prevent excessive shifting. But with the CVT I wonder what the T/H function is accomplishing. Seems like the CVT does all that seamlessly. Thoughts??

BTW, with the CVT are we slowly returning to the 1950's Buick [strike]Dynaflush[/strike] Dynaflow??
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[david]

[p]Charlie:

My room mate in college had a Buick Dynaflow. The engine input shaft was very loosely connected to the output shaft on that transmission. I haven't a clue what was in between. Maybe just a big torque converter. I had a Chevy with a two speed automatic and a torque converter. I bet both of them dumped a lot of horsepower as heat into the transmission.

The Nissan CVT uses a steel belt drive. Two pulleys with a hydraulically controlled diameter (by opening or closing the spacing between the side plates) are connected with a steel belt. It also has a torque converter, but that locks up at 20-30 miles per hour. So the transmission is very fixed but has a variable ratio. Depending n how hard you press the accelerator it choses a drive ratio to suit. It is very smooth, but does feel weird driving it initially.

So, I assume that the non tow ratio of 1,700 at 60 mph not towing and 2,300 rpm while towing goes higher with the tow mode on. That increases (numerically) the drive ratio, lets the engine speed up a bit, and lowers the torque on the engine at the same speed. I also noticed that the coasting ratio stays high, which provides more engine braking than with tow mode off.[/p][p]
[/p][p]Based upon its feel while towing: <3,500 lbs and 60 mph max, I think that I am not stressing the engine in non tow mode. It has plenty of available torque which means I am operating well below the maximum power curve.

I don't remember specific rpm figures when I towed with it on, but I did notice a 1 mpg drop with it on.

The transmission does have a low mode, separate from the tow mode. You select that just like a step ratio transmission with the shift lever. It works similar. It keeps the ratio high (numerically) and won't "shift" upward as you speed up. I use it for downhill braking and it works just like downshifting a normal automatic.

The CVT improves gas mileage because its computer can select the optimum ratio for the load and speed. I think it may be the wave of the future. Nissan has had some "chudder" problems with it at low speeds, probably with the torque converter not locked. Mine did it very occasionally, but not in the last year or so.

David[/p]

[charliem]

[font size="3"]David,

Interesting experience. The Dynaflow was just a torque converter with a two speed +R gear set.

 [a href="https://en.wikipedia.org/wiki/Dynaflow"]https://en.wikipedia.org/wiki/Dynaflow[/a]

I remember seeing variable speed V-Belt drives, both preset and adjustable, so I know what you're describing. It does sound like they have a future. [/font][font size="3"]It also sounds like the tow mode just puts a software bias in the ratio vs HP curve to get higher on the torque curve.[/font][font size="3"]

BTW my college roommate had a brand new Model A. I think his name was Henry   

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