So I guess a 1/2-ton truck is enough

[rgwatkin]

I towed a 28FC for nearly 80k miles with a RAM1500 (5.7L) with no handling issues at all. I did add air bags to boost the springs a bit. There is never a worry about 1/2 axles as the design margin on those are 2x. When is the last time you ever heard of anyone breaking a 1/2 axle? In my lifetime never.

[jcl]

Originally Posted by Bobbo

I realize my limitations. I realize that I don't know enough to agree or disagree. I realize that I don't know enough to second guess the vehicle manufacturer. I realize that I am not willing to risk my family's welfare to my guesswork. I suspect that some don't know their limitations. YMMV.

You are second guessing both the manufacturer and the federal motor vehicle safety standards.

Use your example of the payload label. It is simply a consumer information label. It says that when the vehicle was manufactured the rated GVW was xxxx. It usually doesn’t use the word payload because that word isn’t required on the label. FMVSS define maximum capacity of cargo and passengers as GVWR less curb weight, so if you change the curb weight the cargo capacity changes. Pretty simple. If the manufacturer wants you to carry less than the rated cargo capacity for some reason then they can reduce the GVWR at time of manufacture.

The maximum cargo capacity number on the door jamb label is just for operator convenience. If you want to turn it into an operating parameter distinct from the calculation above, eg assuming it is lower due to vehicle limitations such as stability or durability or whatever, then you are misinterpreting what cargo capacity actually is.

[AlbertF]

Originally Posted by Boxite

Excellent points all. (but I don’t have shocks on my 22’ AS and I’d be surprised if yours does either. They are largely unnecessary on rubber-torsion axles.)

You are correct. Actually, I wish it did have shocks. It bounces too much when lightly loaded, e.g. we're only going away for a couple of nights. It's better when we have water, beverages, food, and other stuff for a longer trip.

[jcl]

Originally Posted by B.trudeau

You are right I don't Know...but you are wrong because I don't assume, I never do!, that is why I rely on MFG notification and that notification is stamped on the door jam, passenger and cargo should never exceed this much load! lots of RV dealer claim to be specialist, and they will do whatever it takes to sell you one of their trailer...after doing all the work like beefing up your receiver and replacing your tires with low profile tire, do you get a signed certification from the dealer stating that this installation is ok to ignore MFG Notice and instruction and fine to go on the road with a trailer that goes beyond your tv ratings? are they liable as per the law for their installation? the specialist of Trailer is YOU and you only should know what you are capable of towing with the number on your door jam simple as that! you can interpret numbers all day long but at the end of the day you are responsible for your safety and the safety of people around you!

You assumed that a particular vehicle, an SUV, was unsafe. It likely didn’t fit your preconceived idea of what a tow vehicle was so you assumed it was unsafe (and insulted anyone who doesn’t tow with a heavy duty pickup.)

If you want to rely on the door jamb label great. In order of decreasing importance, rely on the axle ratings, the GVWR, and at time if delivery, the cargo capacity. You can be within the others and exceed an axle rating, so GAWRs are most important. Then the GVWR. The cargo capacity number on the label is the least important. The moment you install something on the truck, like a tonneau cover for example, it is wrong. Your actual cargo capacity is defined by the FMVSS as GVWR less curb weight. Not curb weight at time of vehicle manufacture, but actual. When I described doing this in a post above you suggested I was wrong and the cargo label was right. You don’t understand the limitations of that label. You assumed that it was an absolute number.

You are conflating tow ratings with cargo capacity. Strengthening a receiver isn’t related to cargo capacity. If replacement tires have a sufficient load rating, regardless of their profile, you can maintain the rated capacity.

Your manufacturer rating is not a legal defence in a crash. You are responsible whether or not you are within manufacturer recommendations. And if you want to rely on the manufacturer’s tow guidance absolutely and literally then you need to make sure you are towing in the same conditions as the manufacturer did when they arrived at that rating. That means towing at no more than 40 mph, trailer brakes disconnected, and with less frontal and bluff area than a travel trailer. Do you acknowledge how ridiculous that would be? You find yourself in that position when you assume things like the tow rating being absolute, and the test parameters and conditions to arrive at that rating not being relevant. If you are going to take the rating literally then take the test parameters literally.

[AlbertF]

Originally Posted by gypsydad

As many here know, longer wheel base tow vehicles do provide a more stable platform for towing. You can say/do as you like about using a car or truck not designed for towing larger TT's...just not for me.

"Designed for towing." What does that really mean?

The assumption is that larger pickups are designed to tow, and smaller trucks and cars are not.

Volvo, to use one example, seems to do extensive towing testing of its cars. So at least some car manufacturers put significant engineering effort into this question. Does that mean they are "designed" to tow, or is their towing capacity simply a by-product of their design, since virtually every vehicle, even a motorcycle, has some capacity to tow a trailer of some size? It's hard to say.

So the next question is, are pickup trucks actually designed to tow?

I'm not sure that any vehicles apart from tractors, whether agricultural or highway, are really designed to tow.

If pickup trucks were, they would be a lot lower (to ensure a low centre of gravity), and have lower profile tires, dramatically shorter rear overhangs, fully independent suspension, boxes integrated with the cabs to reduce chassis flex and allow more effective weight distribution, and be far more aerodynamic (at least to take advantage of the superior aerodynamics of Airstreams). Instead, they are designed with solid axles and high ground clearance for off-road capability and with full frames to allow the ability to exchange boxes for aftermarket truck bodies and equipment. In my non-engineering opinion, their towing ability is primarily a byproduct of their size and mass.

There's a lot more that we could explore. Why are consumer versions of pickups still built this way? How much of this is simply about meeting the expectations of the market, rather than advancing technology? Is this simpler approach (body on frame design and construction) more profitable because it's easier to design for different cab and box lengths?

These are not simple questions, and there are no simple answers. However, it seems to me that there are passenger cars towing Airstreams that have greater real-world towing capability (apart from carrying generators, grills and firewood) than ½ ton pickups, and perhaps even ¾ ton pickups. And this debate is worth having if it moves us closer to the truth of the matter.

[jcl]

Originally Posted by AlbertF

"Designed for towing." What does that really mean?

The assumption is that larger pickups are designed to tow, and smaller trucks and cars are not.....

Good points. I think a case could be made that pickups are designed to town fifth wheel and gooseneck trailers, at least before manufacturers raised them so that some didn't fit under 5th wheel hitches, but not so much bumper pull trailers. They can certainly do it. What they are designed for is carrying cargo, and many people want to carry cargo and tow simultaneously. Fair enough. But carrying cargo remains the primary design objective.

Our early 2000s E53 X5 was certainly designed to tow. The BMW receiver hitch was integrated into the chassis, not simply bolted on. That vehicle had trailer stability control built into the main electronic vehicle stability system, from the factory, on all units built. Not an option. It was activated by plugging in the trailer wiring. Plugging in the trailer wiring also switched the reverse camera to show the hitch ball. On every unit built, not just the ones with tow options.

That vehicle was designed to tow just over 8000 lbs, and tested to the TUV towing regulations, which included a 12% grade. That was a decade before US manufacturers started using standardized tow rating tests.

US truck manufacturers took another 10 years to incorporate electronic stability control into their pickups and sport utilities.

[rgwatkin]

Originally Posted by jcl

You are second guessing both the manufacturer and the federal motor vehicle safety standards.

Use your example of the payload label. It is simply a consumer information label. It says that when the vehicle was manufactured the rated GVW was xxxx. It usually doesn’t use the word payload because that word isn’t required on the label. FMVSS define maximum capacity of cargo and passengers as GVWR less curb weight, so if you change the curb weight the cargo capacity changes. Pretty simple. If the manufacturer wants you to carry less than the rated cargo capacity for some reason then they can reduce the GVWR at time of manufacture.

The maximum cargo capacity number on the door jamb label is just for operator convenience. If you want to turn it into an operating parameter distinct from the calculation above, eg assuming it is lower due to vehicle limitations such as stability or durability or whatever, then you are misinterpreting what cargo capacity actually is.

Not to be flippant but...I do second guess the Manufactures and the Feds. Both have a vested interest in a failure never happening (ie, <10 sigma) to protect their butts not in optimizing a practical cost effective product for the customer.

[dznf0g]

Originally Posted by jcl

Good points. I think a case could be made that pickups are designed to town fifth wheel and gooseneck trailers, at least before manufacturers raised them so that some didn't fit under 5th wheel hitches, but not so much bumper pull trailers. They can certainly do it. What they are designed for is carrying cargo, and many people want to carry cargo and tow simultaneously. Fair enough. But carrying cargo remains the primary design objective.

Our early 2000s E53 X5 was certainly designed to tow. The BMW receiver hitch was integrated into the chassis, not simply bolted on. That vehicle had trailer stability control built into the main electronic vehicle stability system, from the factory, on all units built. Not an option. It was activated by plugging in the trailer wiring. Plugging in the trailer wiring also switched the reverse camera to show the hitch ball. On every unit built, not just the ones with tow options.

That vehicle was designed to tow just over 8000 lbs, and tested to the TUV towing regulations, which included a 12% grade. That was a decade before US manufacturers started using standardized tow rating tests.

US truck manufacturers took another 10 years to incorporate electronic stability control into their pickups and sport utilities.

Hmm, GM introduced stability control in cars in 1997 and in SUVs in 2006.

[jcl]

Originally Posted by dznf0g

Hmm, GM introduced stability control in cars in 1997 and in SUVs in 2006.

Agreed, I should have been more specific. They added trailer stability control in 2012, from my notes. Was it earlier?

[dznf0g]

Originally Posted by jcl

Agreed, I should have been more specific. They added trailer stability control in 2012, from my notes. Was it earlier?

You may be intermixing terminologies and technologies. Stability control has always included whatever forces act upon the TV and begin to cause slip.
Trailer sway control intervenes when sway is detected by accelerometers before any slip occurs. They work hand in glove.

[jcl]

Originally Posted by dznf0g

You may be intermixing terminologies and technologies. Stability control has always included whatever forces act upon the TV and begin to cause slip.
Trailer sway control intervenes when sway is detected by accelerometers before any slip occurs. They work hand in glove.

My system in 2000 was called Dynamic Stability Control. It was developed by Continental IIRC It considered forces that acted on the vehicle. Trailer Stability Control (TSC) was an additional mode or algorithm incorporated within DSC that identified trailer sway based upon detection of those cyclical forces acting on the tow vehicle, in conjunction with the steering wheel angle sensor. It did not detect forces on the trailer, as aftermarket trailer stability control systems with accelerometers mounted on the trailer do. It also did not apply trailer brakes, since Euro vehicles did not have electronic trailer brake controllers. Still, it was pretty good for 2001.

GM announced the incorporation of trailer sway sensing to Stabiltrak in 2012.

https://media.gm.com/media/us/en/che...iler_sway.html

Edit: I found a reference to Ford introducing a similar TSC mode on their 2009 model.

[Bobbo]

Originally Posted by jcl

You are second guessing both the manufacturer and the federal motor vehicle safety standards.

I am not second guessing anybody. I am accepting the manufacturer's posted limits. It seems to me that you are the one advocating ignoring the payload rating.

[Steven62]

“towed a 28FC for nearly 80k miles with a RAM1500 (5.7L) with no handling issues at all. I did add air bags to boost the springs a bit. There is never a worry about 1/2 axles as the design margin on those are 2x. When is the last time you ever heard of anyone breaking a 1/2 axle? In my lifetime never.”


Hate to admit this but our axel did break last spring in Idaho. Trip started in the Florida Keys, after the repair continued to Banff and Glacier then across Trans Canada back home to New Hampshire 2017 Ram 1500 (5.7), 25FB. Only issue in 7 years of towing 25FB with the Ram 1500.

[B.trudeau]

Originally Posted by jcl

You assumed that a particular vehicle, an SUV, was unsafe. It likely didn’t fit your preconceived idea of what a tow vehicle was so you assumed it was unsafe (and insulted anyone who doesn’t tow with a heavy duty pickup.)

If you want to rely on the door jamb label great. In order of decreasing importance, rely on the axle ratings, the GVWR, and at time if delivery, the cargo capacity. You can be within the others and exceed an axle rating, so GAWRs are most important. Then the GVWR. The cargo capacity number on the label is the least important. The moment you install something on the truck, like a tonneau cover for example, it is wrong. Your actual cargo capacity is defined by the FMVSS as GVWR less curb weight. Not curb weight at time of vehicle manufacture, but actual. When I described doing this in a post above you suggested I was wrong and the cargo label was right. You don’t understand the limitations of that label. You assumed that it was an absolute number.

You are conflating tow ratings with cargo capacity. Strengthening a receiver isn’t related to cargo capacity. If replacement tires have a sufficient load rating, regardless of their profile, you can maintain the rated capacity.

Your manufacturer rating is not a legal defence in a crash. You are responsible whether or not you are within manufacturer recommendations. And if you want to rely on the manufacturer’s tow guidance absolutely and literally then you need to make sure you are towing in the same conditions as the manufacturer did when they arrived at that rating. That means towing at no more than 40 mph, trailer brakes disconnected, and with less frontal and bluff area than a travel trailer. Do you acknowledge how ridiculous that would be? You find yourself in that position when you assume things like the tow rating being absolute, and the test parameters and conditions to arrive at that rating not being relevant. If you are going to take the rating literally then take the test parameters literally.

Sir you might be right, and no way I'M here to insult anyone towing with an SUV I did it myself with a Grand Cherokee pulling a 25FB! I understand perfectly you're numbers and explanation I am no scientific Towing Mathematician! and I will keep reading about this, however when you say I assume for my own specific case I'm not (in my mind) because I refer to my owner manual and the payload sticker on my door Jam, and as per all that cargo I add to my F150 I am going farther than the limit, this said, a half ton truck has higher metrix than most SUV, this is why IMO an SUV is not suited for towing something like a 25ft trailer and more. Anything added to the truck, Fiberglass cover, tool box, cargo rubber mat etc, add to the cargo payload!
It is a particular subject and it seem everybody has number and physical theory about what should influence a TV to tow a trailer according to its weight, lenght, highs etc. If your safe with your equipment and you drive safely then everything is allright really! seem like everyone has its own little idea on how to go about it!
Thank you for your reply

[Slimpockets]

My old ride is nice but a larger bathroom, ducted air, composite floor, and disk brakes would be nice. I could get used to the never-lube bearings too.

I’m not the kind of guy to replace things that are working well. I guess I’m getting soft as I age. I’m going to keep an eye out for an upgrade. I just hope it is an upgrade.