I have noticed that all commercial "car" carriers secure the wheels/tires to the trailer. This obviously allows the suspension to work and the cars move around a fair bit over uneven surfaces.

Is this behavior better for some reason, or is it a matter of convenience? I am guessing that attaching the wheels/tires makes for a consistent manner and method of securing. But it seems to me that allowing the sprung mass of the vehicle would make for a less stable load. Maybe it doesn't matter, especially on a large, purpose built trailer.

OTOH, it seems that the added effective weight of a vehicle settling back down to the bottom of its cycle would not only add unnecessary stress to the trailer, but could actually "overload" it if you were near the weight rating to start.

I am especially curious after trailering a car 400 miles yesterday. The "obvious places to attach straps (I only have conventional straps with hooks on the ends, not ones designed to fit tires) were a lower control arm in the back, and "tow hooks" mounted to the subframe in the front. So while the front theoretically could have moved a little bit over really big bumps it was pretty well locked into place. It pulled very nice and stable. It was disconcerting enough to have this guy constantly tailgating me, I would have found it even more so if it was bouncing up and down...

Thoughts / guesses / evidence?

 

I've only towed with uhaul trailers, they all are set-up to secure wheels and strictly say do not secure car body to trailer. 400mi trip, probably didn't hurt anything. I wouldn't do it again.

 

I haul my Corvette race car on a flat bed using over the tire straps. It works great. I've towed it all over the west for the past 3 years with no issues. The car does move up and down over whoops in the road but it doesn't seem to affect anything. Tying it down by the wheels, the straps never come loose from the body moving around, like they can when securing to a body mount.

 

When you attach anywhere that is part of the sprung mass of the vehicle it will go down when you hit a bump then back up pulling on the strap or method of securing it. It is a far better idea to secure the wheels as they are static and dont move up or down with bumps. Nylon straps have some level of stretch and constant loosening and snapping tight again can cause them to work slack into the buckle. Or they can use the weight of the vehicle pulling up after a sudden drop to get more slack out of the turnbuckle/ratchet by tightening the strap wrapped around it. There is nothing wrong with securing to the sprung mass per se as long as you check the straps frequently. This is also the reason why you see so many ratchet strap parts laying all over the highway.

 

Before the wheel straps came into play all new car haulers had hooks that fit into holes or slots in the frame and they would "squat" the suspension.
Now my thinking is vary few cars, SUV's and some light truck have frames so putting the hooks in a hole / slot could bend and pull out.
You also had to squat the suspension because of the loading and unloading the chains could come out and not the load is loose = not good!

Now if your trailer, like mine, dose not have the tie downs, E-Track?, for the tires how do you use the tire straps?
If you only hauled 1 thing, say race car, once you knew where it sits on the trailer you could add tire tie downs but then if you haul something else and it dose not sit in the same place then what?

I have hauled a lot of different cars, SUV's, pickup's and even a van on my trailer and never had a problem with straps to the rear axle and front cross member or A arms.
I use axle straps, they are short straps with 2 loops and a cover over the strap to protect it, that you hook the ratchet strap to and the other end to a D link on the trailer.
I cross (X) the rear straps so the rear cant move side to side, yes before I did tis I has a small light car shift on the bed, open center bed.
The front is just straight on as the weight of the motor has kept the front from moving. I also squat the front suspension when on the front / motor cross member.
CT to OH & back more than once for racing

Not this car but another one I have, CT to NJ or MD and back many times for racing but you can see they sit different on the trailer.

I hauled the race car above, the other Gremlin not pictured and a 2nd Javelin, like the race car from CT to NC when I moved without issues.
Just my .02
Dave ----

 

All good thoughts/points - thanks!

FYI, I did stop and check the straps about every 100 miles. The first 2 times they were no longer as tight as I wanted. The third time they stayed snug.

I don't expect to do this again (I mostly use it for my tractor, which has no suspension...) but if I do I will keep these ideas in mind.

Thanks again!

 

I would check mine in about 50 miles and take up as needed then at every gas stop but i knew how tight I had to go for them to stay tight.
It dose not hurt to ask like you did and maybe others who read this will know if they have to haul something.
Dave ----

 

Mac's makes straps for towing cars on trailers, their site has good info on strapping a car.

 

Think about it from the perspective of a business owner who's hiring a coked up foreigner to drive a wedge full of cars across the country or the absolute dregs of society to run a rollback at 2am and it all makes sense. It's way easier to get those kind of people to do a wheel strap right because it takes less care at the time of connecting them to be sure they're done. Strap goes around the tire and nowhere else and gets tightened, real simple. It's much easier to route a chain somewhere stupid that puts force on something it shouldn't (especially on a low modern car without much easy access) or to not compress the suspension enough with a T hook and then you've got an angry customer asking why their car is broken in some way or another. And as a bonus every car is the same, no looking around for hook slots.

The downsides of wheel straps is that they the damper action tends to make the trailer handle worse (which is why rollback drivers often still use the winch to compress the front even though the vehicle is strapped) and they loosen up way more often than straps or chains properly fastened to the chassis. And straps wear out far more quickly than chains hooks and binders, but they're cheaper, and you can't easily scratch things with them.

Use whatever you want, if you use it right it won't matter.

 

On a rollback, the operator still needs to hook onto something to pull the vehicle up onto the bed. Wheel straps are not going to work.

 

I'm talking about once it's already on the truck. They pretty much all use wheel straps to tie down these days.

 

That was pretty much my hypothesis.

My conclusion after all the responses (thanks ALL for replying honestly and without rancor or belittling comments) is that either will work fine, if one understands the dynamics (no pun in ten did) of strapping on a trailer.

Best,

 

Having been towing, trailering and recovering cars/trucks/equipment and what not since appx 1986, USMC 3523, Vehicle Recovery Mechanic, 1986-1992, the securing method does change depending on what it is...
Say a tank, or HE of some sort, skid-steer etc.., chains and binders and and dog it down tight, then I usually stopped maybe 30 mins/50 miles in and checked everything, and as Fuzzface said, then at gas stops or piddle breaks, and make sure everything is still how it should be.

For cars/trucks back in '93 when I drove a tow-truck in OC, they had the chains with the T-hooks and the J-hooks, I never liked doing it that way, as you had to put some healthy force on the chains to settle the suspension down as ****-sideways stated. And yes, there were some coked up dudes I ran across in the towing business... had to fire 2 because of it, drugs and doing tows on the side when they were allowed to drive the trucks home. 🤦‍♂️

I've had my Big Tex flatbed since like 96/97 and have hauled over 50 (at minimum) trucks/cars and I have used the nylon ratchet straps with zero/nada/zilch failures, on my trucks in the front I go over the I-beam or axle if 4x, and back towards the ratchet to another tie-down point close to it. On the rear, same thing, over rear axle back towards ratchet, I try to go as far out towards the wheels as I can. Seems about 10-12 yrs ago or so, the big thing became guys crossing the straps, R side of vehicle to L side of trailer and vice-versa. I've just stuck with 4 straps straight, 2 up front, 2 in the rear, never had one loosen or fall off.


Funny I saw this post, this weekend I was just pondering buying some of the wheel net types for my trailer to see how I liked them since a couple of my straps are due to be rplc'd soon, I haven't experienced any of them bouncing excessively and causing issues, so I can't see a huge difference in going to the wheel net straps...

 

If a vehicle is tied down tightly, the bump would add more load to the trailer axles than if the vehicle's suspension can join the equation. Like if the same trailer were the hauling the equivalent weight of bricks.

If the vehicle's suspension can join the equation, the same bump will compress the vehicle's suspension, the vehicle will move upward less than the trailer, the trailer will settle, then the vehicle will settle more gradually than if it were tightly locked to the trailer.

Either way, the trailer's weight rating takes bumps into account. Yes, a 10,000 pound trailer weighs 10,000 pounds sitting still and on a smooth road, and it would weigh more at the instant that it goes over a bump if we could weigh it at that exact moment. Tires and suspension is designed for this within reason.

LOL yeah I've caught myself on long drives with a car on a trailer in back going "WTF?!?!? . . . oh yeah. Whew."

I take this as a sign of a good tow vehicle towing a trailer that tows well and is loaded well to the point that I forget it is there.

I wish U-Haul sold their car hauler trailers as car hauler trailers! They are excellent for many combinations (but not all). I know why they don't, but that doesn't make me want one any less.

In the meantime, we are stuck finding other means. I've most-often used flat or dovetail trailers, usually with wood decks, to haul cars. A lot of modern cars don't have a good place to hook besides the wheels. Older cars with real frames are easy to hook to the frame or axles or control arms etc. when everything is built sturdy like they did back in the day. I have noticed a couple of slightly-deformed frame holes after tying down with short spans of strap/chain and going over big bumps somewhere along the way. These have been on big sedans where I think the bump causes a compression that loosens the strap or chain, and then when the car rebounds it yanks tight. I solved that by tying criss-cross, which I think allows more give and movement over the bumps.

I have no issue tying just the tires down, but I try to take it easy on what angles I pull from. I've seem some where they tie down the tops of the tires pulling outward so hard that it looks like the car has severe positive camber all around. Not sure if there is any real harm there, but I feel bad for the wheel bearings and suspension parts anyways. Going over bumps, I suspect that independent suspension would have a tendency of pushing the bottom of the tires out on bumps as the tires try to camber negative on compression. For a short and smooth haul, I suppose it wouldn't be bad.

On tow dollies, I always wonder if the tow dolly hits bumps harder then falls back to the ground faster than the unsprung mass would otherwise do on the car that's strapped to it, and that this might cause a problem, but have never seen it be a problem. If this were an issue, it'd be much less of an issue on a typical car hauler with trailer springs and the suspension of the tow vehicle involved.

 

My side-by-side goes in my toy hauler, so nobody can see the cluster I've come up with to secure it. I connect everything in this order.

Ratchet straps over the front bumper. There are no tie-downs in a good position to use tire bonnets.
Tire bonnets over the rear tires. I had to add tie-downs to make this work. Otherwise the existing tie-downs were putting a lot of stress on the wheel hubs/bearings because they were so far to the side.
Chains and binders to the frame. This prevents excessive body roll. My side-by-side is kind of tall and wide. If allowed to sway it can come into contact with the trailer cabinets on either side.

It's not ideal at all. I wish that I had E-Track on the floor of the toy hauler. That would make things a lot easier on me, the side-by-side and the trailer. My little ATV trailer uses a form of E-Track and it's so much easier.