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Question Towing

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Just because it will pull it does not mean it will handle it. You are looking at the wrong numbers and not understanding what they mean. I have owned an 1967 88 and a 1967109 Safari wagon with a 302 Ford V8 in it and I have an 82 Range Rover with a 4 speed transmission and original 215 cu V8. Only one of these vehicles is capable of towing that 28 ft Airstream. Guess which one......
 
The weight rating may look ok for towing. I would be concerned with stability. I would want a longer wheel base on the tow vehicle for a 28’ TT. Good luck with the decision.
 
Our keep liberty had a nice towing capacity as well.

Researching further though led to some interesting info about the height of the liberty, wheelbase, etc that essentially moved it out of the “should you tow a trailer with it” list.

Lots of stories online about those that tried and how “squirrelly” it was towing a trailer.

As has been noted, other things to think about other than just the weight factor.
 
Lets put some numbers to this,

Discovery wheelbase 115" per this link


Recommended "rule of thumb" wheelbase for 28' Travel Trailer per this discussion 142".


If you feel this measure has merit, your looking at a 27" difference a 23% diff in recommended wheelbase. Angles and Levers seem to make some sense to me. Greater distance between wheels sounds logically to be more stable.

The Discovery vehicle empty weight is a reasonably hefty at 5,569lbs, which adds some to stability. Tires opens a whole other discussion.

Then there is this Camp

(source: Wheel base-to-length-ratio )

The most significant factors involved in tow safety for a conventionally hitched trailer are:

1. Trailer weight vs. tow vehicle tow ratings. Mfr tow ratings evaluate the capacity of truck drive train strength, suspension, brakes, and engine and cooling system adequacy. Trailer weight is gotten, if you own the rig, by weighing it on a scale or, if you do not own it, by using the mfr's gross vehicle weight rating (GVWR) as a good, conservative approximation.

2. Trailer balance. Trailer balance is determined by the position of the trailer's center of gravity (cg) with respect to the hitch coupler. Stability demands that it be well forward so that at the very least 10% of the trailer's weight bears on the hitch. Think of a trailer-tow truck rig as a seesaw. The trailer CG sits at one end, the hitch bail is the fulcrum/pivot, and the truck's rear axle sits at the other. The further that trailer CG is from the hitch, the more leverage it has over the truck and the more unstable the tow is. The hitch/tongue weight's percentage of trailer weight is a measure of that lever arm, the more that bears on the hitch, the smaller the arm that the trailer can exert.

3. Type of hitch. Trailer tongue weight exerts a force on the truck behind the rear axle, pivoting the truck about its rear axle and lifting the front axle. This act to increase the oversteer of the truck making it unstable with respect to lateral forces like steering or trailer yaw (sway). Weight Distributing (WD) hitches are design to force the transfer of the hitch weight forward to the front axle of a truck to return it to its normal attitude and under-steer condition and resistance to lateral forces. Most use spring bars between the ball mount of the hitch and the A-frame of the trailer to pivot the truck forward in the vertical plane.

4. Hitch sway control. This is added to WD hitches two general ways. It is added on in the form of a friction bar connecting the hitch ball mount with the trailer A-frame. The other is to design the anti-sway into the operation of the weight distribution. I greatly prefer the latter way as employed in Reese Dual Cam, Equal-i-zer, and Hensley Arrow hitch systems.

5. Truck and trailer tire resistance to lateral forces. This is a function of tire design, weight rating, and proper inflation. My Bronco uses big BFG all terrain LT 31x10.50x15R m+s gum-balls inflated to max pressure as indicated on the sidewalls for towing. I have TS tires on the trailer tho LT would do as well -- P rated tires are not recommended.

6. Trailer lateral surface area Long trailers naturally have large sides for lateral aerodynamic forces -- cross winds or passing truck shock waves in other words. The yawing effect is resisted by all of the foregoing countermeasures and the simple tactic of slow down in cross winds!

As far as trailer length is concerned, it is useful only as a indication of general GVWR and, of course the #6 factor."
 
Each one of those points made require an education into what is proper, how to install it, which to buy, and the end use of them. No one is born knowing how to tow things. Sometimes getting the experience can be traumatic. Stay within limits set by people with experience and survive the learning experience.
 
Great research Joe!(y)
 
and if things don’t go well, there is this:
I agree with most of that but I would advocate earlier and heavier use of the trailer brakes within reason (I think there is some CYA in the article) and also cover the gas pedal as it may be helpful to accelerate a bit once the trailer brakes are applied depending on how much sway you have and how quickly it is coming under control, although I agree this would be a bad idea if you were going down hill at the time. Towing is a skill acquired by experience so its best to keep speed down, especially if towing at the margins of safety. The faster you are going, the faster things happen and the less time you have to straighten things out.

Also trailer tire choice is important. I know of only two trailer tires made in the USA - Goodyear Endurance and Carlisle. I don’t have experience with Carlisle although they get good reviews. I use Goodyear on my horse, equipment, and utility trailers and have never had a problem with them. I would never use Chinese trailer tires.
 

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