Towing with a minivan

[hommer638]

Hi to all on RV.Net. I have a 2011 Toyota Sienna with the tow option that is capable of towing 3500 lbs. I also just purchased (not taken delivery at this point)a 2018 Forest River Wolf Pup 16FQ that weighs 2919 lbs empty along with an equalizer weight distribution hitch. I would like to here from anyone who has a similar set-up and how they are making out towing with a minivan. Any information would be greatly appreciated. Lou.

[RSD559]

Weight concerns have already been addressed so I won't go there. What I'd like to bring up is how miserable you will be, in the truck lane, doing 35-40 mph, peddle to the floor, while everyone else is doing 70, just to get to the other side of that mountain. You won't have little hecklers complaining about how everyone is passing you, including motorized wheel chairs, like we did. But it still is not going to be fun.
I second the transmission cooler suggestion. Some mini-vans don't have external coolers. My son's Honda mini-van didn't have one. He didn't notice it until he was in getting his transmission replaced. They suggested getting one.

[GKAbbott]

Unless you are absolutely dead set on that trailer, I recommend you look at A frame style pop-ups. We towed a 12 ft A-liner behind our 2012 Grand Caravan. Loaded weight was under 2500 lbs. Tongue weight was about 290 lbs. I installed a break controller and trailer breaks. Towed it over 20k miles before selling the camper. Still have the Caravan. Looking for another A frame style to travel in. It's more economical to change campers than tow vehicles. Of course, if you have already taken delivery of your camper, disregard this post.

[hommer638]

This whole thing was a real eye opener to me. I am happy that my RV did not come in on time for me to pick it up before there was too much snow on the ground for me to bring it home safely. This delay just gave me enough time to ask questions and get the answers I needed. I do hope this thread helps those in a similar situation and avoid a possible disaster and hardship on the road. Vacations and rving are supposed to be fun and nobody needs the hassles brought on by a bad setup. Next spring when I pick up my rv I will have a proper tow vehicle.

[BenK]

Jeremiah,

Tongue weight in discussion is at a 'static' loading...that static load becomes much, much higher in a dynamic situation. Plus as you said...a single axle will have the weight tossed back and forth easier than multi axle trailers

Like in a whop-d-do, RR tracks, pot-hole, etc, etc A 400 lb static tongue might have a dynamic weight load hundreds or more

What it gets to is not easy to figure out. Even in a laboratory it would need tons is expensive and large equipment

Won't happen over night either. Those pictures are of failed spot welds that took a lot of time to get to the point where they gave up. The more over their design ratings...the faster/sooner they will fail

Why ask newbies how they drive, where they drive, etc that creates ever higher dynamic loads. Toss in compressing WD bars loading even more to exacerbate this whole loading situation during compression and the release of that compressed WD bar married with the TV Suspension release...

OP...glad you made a decision and posted back. Ask that either link this thread to your new purchase thread and/or post one here and then start your new thread

There are many, many lurkers who follow 'advice' here and can learn a lot from your thread...THANKS

[hommer638]

I would like to thank everyone for there honest answers. It just confirms what I knew all along that the sienna is just not built to tow anything more than a tent trailer which it does just fine. What amazes me is that I called four different rv dealers and every one of them told me that my van was more than capable of towing that model travel trailer.
I am now in the process of choosing a new tow vehicle so I will start a new post to ask your valued opinions on my choices.

[mkirsch]

I don't see any "sky is falling" anywhere in this thread. In fact the advice seems unusually logical and common sense for this site.

You can't realistically sit there and say that it makes sense to tow a trailer that STARTS at the minivan's maximum tow rating, and goes up from there.

[dodge_guy]

This “sky is falling thread” has got to be the worst I’ve read on here! The pics you posted would happen if you were towing something extremely heavy! I’m talking heavy!!!! Or from an accident that ripped the hitch off. Bottom line is for what most people would think intend to pull with a unibody car/van you will never see this type of failure.

I towed with my Full size Dodge conv. van that had a unibody chassis and it never failed. I’ve seen minivans towing large PuPs or small TT for years with no failures.

[jerem0621]

rexlion wrote:
Jeremiah's popup exceeded the van's hitch weight limit by a substantial amount, so the result is not surprising. Towing within the tug's specified limits, or a bit over the limit with accompanying hardware (i.e., a custom receiver to spread the load over more of the unibody), should yield a different result.

Vans are better at maneuvering than more top-heavy full size pickups and trucks. They have a pretty long wheelbase, good for stable towing. With brakes on the trailer, they stop fine, too. They can do a great job of towing. They won't, however, tow nearly as much as a larger vehicle.

I like some of what Can-Am does, but I don't know exactly how far they push the envelope. If they were to say that a minivan can be set up to tow a 28', 5000 lb TT with 700 lbs of tongue weight, I'd say no thanks (I don't know if they would do this, it's just a for-instance).

You are absolutely right. Thing is, this PUP had a dry weight in the 2,700 on range and topped out about 3,300 lbs. It was a reasonable PUP and not all that uncommon. Thing is, I believe that this heavy tongue weight happens a lot on single axle trailers. And can be a challenge to know if your trailer will be in the weight range.

Just be a warning to all minivan tow'ers. weigh the tongue weight before you buy. Especially if the trailers design limits you on how you can manage the tongue weight.

Thanks!

Jeremiah

[BenK]

Instead of answering the PM's individually...here are the answers and pictures to help understand what am saying

Lots of different ones in hopes to get the visualization of the various ways they put together vehicles

A monocoque/unibody will have a WD Hitch system bolted to the 'sheetmetal' or 'pan' portion and it will then transfer the WD forces from that receiver to the pan sheetmetal...which then transfers those forces to the other sheetmetal panels via spot welds. Some will have glued interfaces (bonded), with some additional fasteners.

At those joints will be the stress raisers and of which the issue with WD on monocoque/unibody's ability to transfer and last over time.


A platform is just that, a pre-designed pan or in today's design systems...a whole basis to bolt/weld/glue/etc the body panels to make a vehicle.

the platform can be the same for a 'car' to a 'CUV' to a 'mini van', etc


These are 'pan' platform

VW like the one used to build my Dune Buggy. Notice the holes along the perimeter and are the holes for the bolts to hold the body to this pan







and this one shows the body that is already mounted onto the pan next to it




This is a current type platform and is not like the older 'pan' platforms. There is still a pan, but the body is now part of the platform. If this platform was used for, say a mini van, the body would look very different, but the 'pan' area would be the same with whatever the designers spec'd out to increase the strength/stiffness/etc




This is a 'CUV' with no ladder frame, but a unibody




These ladder frames and will have a monocoque/unibody mounted on top of it

This is a ladder frame from a truck


This is a ladder frame and think for a truck


This is ladder frame is for a 'car', not truck



This is a split image tied together (left and right) showing the difference types of cross members, and stuff mounted



This is a ladder frame for a 'car'

[rexlion]

Jeremiah's popup exceeded the van's hitch weight limit by a substantial amount, so the result is not surprising. Towing within the tug's specified limits, or a bit over the limit with accompanying hardware (i.e., a custom receiver to spread the load over more of the unibody), should yield a different result.

Vans are better at maneuvering than more top-heavy full size pickups and trucks. They have a pretty long wheelbase, good for stable towing. With brakes on the trailer, they stop fine, too. They can do a great job of towing. They won't, however, tow nearly as much as a larger vehicle.

I like some of what Can-Am does, but I don't know exactly how far they push the envelope. If they were to say that a minivan can be set up to tow a 28', 5000 lb TT with 700 lbs of tongue weight, I'd say no thanks (I don't know if they would do this, it's just a for-instance).

[jerem0621]

Thanks for the pics and the explanation BenK. Very good detail. I'm book marking this for future use when folks talk about towing heavy with a WD hitch and a Unibody vehicle.

OP, great decision.

Thanks!

Jeremiah

[p220sigman]

I think you are making a wise choice to go for a more capable vehicle for that trailer. While minivans can make great tow vehicles, that trailer is simply more than they are designed to handle. I don't mind towing with our Sienna right at the max, but it is a PUP so low profile and we tow around Florida where it is almost all flat towing. Tough to beat the 16 mpg we get towing. However, I would not want to tow a full-height trailer with it.

[blofgren]

hommer638 wrote:
I had it in the back of my mind that I would need a better tow vehicle. I am planning a trip to the east coast and then a year later a trip to the west coast.I have been looking at the Ford F150 XTR with the 3.5 ecoboost, my son has one and it looks like a very capable and fuel efficient truck.

Great choice; the power they produce is amazing especially for such a small engine.

The biggest challenge then will be resisting the urge to go to a bigger trailer! :B

[BenK]

jerem0621 wrote:
snip...

With the WD, like I said, it did great. But, I think the WD hitch has loosened up the uni-body somehow. The doors don’t seem as tight and the interior body panels now rattle more than they use to before we towed with the WD hitch.

Good buddy, glad you posted this and am taking the opportunity to explain how or why a unibody isn't a good candidate for towing heavy with a WD Hitch system

A monocoque/unibody has a thicker gauge pan or platform with a body spot welded to it. Some of today's are bonded (glued) to the pan with 'some' fasteners and/or spot welds.

A ladder frame setup will have the WD Hitch load on the ladder frame and the body (monocoque/unibody) sitting on top if it via compliant doughnuts

Spot welds are typically NOT continuous seam welded, but staggered (pitch or centers spaced as specified by the engineering drawings)

The forces on a ladder frame are transferred to the frame via bolts holding the receiver to the frame rails. Some to the cross members (not a good way and why some TV's has a lower WD tongue rating).

Since not seam welded...spot welds focuses forces on a small area. That becomes a stress raiser if over loaded (over the design loading)

Stress fractures and then tearing to finally ripping apart. They why of squeaks, groans, etc. To mis-alignment, as the part no longer is to spec

Monocoque/unibody are tighter and stiffer than most any ladder frame...when new...as the compliant doughnuts allow more movement, even when new



Took a few minutes searching for examples



This one shows spot welds in 'shear' how it held, held, held...till the upper spot welds gave up. The top one ripped apart by tearing the a piece away. The second one tore and let go at the spot weld itself. The third one held, but the surrounding material developed stress fractures that was the parting line when the two above let go






This one shows spot welds in 'peel' and tore apart from the bend side to leave material on the other side of the spot weld. The first micro fractures were on the bend side and propagated around the spot weld and finally tore around the spot weld





This one is another spot weld failure in shear and IMHO, too close to the sheetmetal edge vs the forces it was 'trying' to hold against. The spot weld itself is pretty good and the material was either not thick enough or as stated above, too close to the edge




Just one more examples of spot weld failures and telling of the squeaks, groans, etc vehicles that have spot weld failures. The noise is from the two parts of a fracture touch each other while trying to hold it together





In some cases, a vehicle will 'dog track' and/or take more steering input if the looseness if severe enough to allow mis-aligment of suspension/steering components. Bottom line is that the integrity of the whole is compromised and my fear is during an emergency maneuver or accident...the monocoque/unibody might come apart...and the basis for my advice on this matter...follow your OEM's requirements (recommendations) and NOT tow above their rating and NOT use WD when they say 'not recommended'...

Folks gotta decide on their own risk management decisions and think too many have no clue on how a monocoque/unibody works/constructed and fails from over loads...