Wheelbase and towing (again !!)

[waternwaves]

Ken L et. al.

This issue is complicated enough...... mixing apples and oranges (Tow vehicle suitability and mac engine size increases) here is NOT going to provide many more individuals greater insight.

There are many design issues associated with towing.

Hitches have only a few Specified DOT controlled issues and specifications......

And for the vehicles........
some specifications from
Consumer Guide

2005 Endeavor

Torque (lb-ft) @ rpm 255 @ 3750
Curb Weight, lbs. 4079
\Horsepower @ rpm 215 @ 5000
225-hp 3.8-liter V6 and a 4-speed automatic transmission with manual shift gate. All offer front-wheel drive or all-wheel drive that lacks low-range gearing and is not intended for severe off-roading. (Their statement not mine)
235/65R17 tires

even within this page two separate horsepower max's are given for the Endeavor.


vs
for a an F150
Size, liters/cu. in ..... 4.6/281 ....... 5.4/330
Horsepower @ rpm 231 @ 4750 300 @ 5000
Torque (lb-ft) @ rpm 293 @ 3500 365 @ 3750
Model............. reg......LB....5.5B....6.5B.....extB...crew
Wheelbase, in. 125.8 144.5 132.5 144.4 163.0 138.5
Overall Length, in. 211.5 230.1 218.0 229.8 248.5 224.0
Overall Width, in. 78.9 78.9 78.9 78.9 78.9 78.9
Overall Height, in. 72.8 72.9 73.1 73.1 73.1 73.1
Curb Weight, lbs. 4788 4908 4993 5115 5451



vs toureg
Engines dohc V6 dohc V8 Turbodiesel sohc V10
Size, liters/cu. in 3.2/195 4.2/252 4.9/300
Horsepower @ rpm 220 @ 5400 310 @ 6200 310 @ 3750
Torque (lb-ft) @ rpm 225 @ 3200 302 @ 3000 553 @ 2000
Wheelbase, in. 112.4
Overall Length, in. 187.2
Overall Width, in. 75.9
Overall Height, in. 68.0
Curb Weight, lbs. 5086



Now with the variances of tire contact patch area, frame stiffness, vehicle torsional rigidity, Suspension flex, number of axles on the trailer, loading differences....Weight distribution, Distance from the hitch point to the rear axle etc....all affecting towing ability, and, despite claims to the otherwise

)A shorter wheelbase vehicle has less lateral stability than the same weight of vehicle with a longer wheelbase.

But most importantly, and strangely enough, few are noticing what Moe is trying to put across here.... A better performing tow vehicle will have a stiffer frame, longer wheelbase, greater load rating, more torque, stronger components..... preferrably vehicle tire contact area greater than the trailer tire contact area.. tow vehicle weight greater than trailer weight...etc.

1) Towing with a vehicle lighter than trailer on a coventional 2" round ball hitch is not the Best Practice, and a sway control hitch will improve the ride and handling, but does not remove all of the problem
2) An unloaded 40 ft trailer on a tractor trailer rig passing you at 70 mph vs your 60 mph, separated by 3 ft. or less is going to move and sway a Mac and trailer. Comments like " The trailer does not sway and the vehicle handles great" are at best a triumph of hope over reality). The laws of physics are not rescinded by kind words....
3) Tow Vehicle differential gearing and engine cooling are critical.
(IS someone implying here that a Toureg , endeavor or other similiar size and weight vehicle is going to perform the same as a full size rig) I deal with contractors that haul trailers loaded all the time......those rigs are not light.. and I cant say that they have been beating down VW factory dealership doors for the new fantastic wunderkind tow vehicle.

At best the toureg is not the tow vehicle the 2500/250 truck is.,

It does look to be slightly less than a 1500/150 truck for handling and performance.

and I think all would agree a 1500/150 truck is sufficient for a mac.
is it enough for a lightly loaded mac.....towed and trailer vehicle weight the same....... perhaps.....? After my test drive yesterday..... I think I still prefer a 2500/250 for handling and performance


now I am also sure that I do not have the most +4,000 lb trailer towing experience on this forum, (i am sure 70,000 miles is not enough to take that title) But there are no vehicles that tow that weight of trailer....., (My average non horse trailer weight is a little over 5400, ) with more stability than the long wheelbase full size rigid frame offerings from the american big 3 and now toyota and nissan. (including of course their culture coached suburbans, Expeditions, Excursions, Invasions.......Annnihiliations......etc..... ( In fact I keep my beast just because it is hard to justify getting rid of a perfectly good handling low cost easy to maintain (Alright.. i see all the old dead ford jokes coming... so save them) F250/460.


Most people tow rarely.....
as a function of the total miles on a given vehicle the full size rigs are better suited to towing. And yes I freely admit (here in front of god and everybody) I have used a little Mazda b2000 with a class 2 hitch to haul a mac for a couple of hundered miles when I was stuck in the wrong place without my regular tow vehicle....... (3000 lb truck with 88hp) But it is not as safe as towing with the F-250

And I will guarantee that you too will be responsible if your overloaded trailer, or overloaded tow vehicle exceeds either DOT, Vehicle manufacturer, hitch manufacturer, or tire manufacturer specifications. And you will most likely find your vaulted insurance useless if the insurance company finds you willfully violated those specfications and operated contrary to them. And as stated elsewhere.......that assignment of some of the blame to you, is far beyond most peoples catastrophic liability insurance is going to pay out.

And most likely since you own a mac, Ya aint in rich man's tax bracket where you can drop 2-4 million for an at fault claim.

And as far as boat recommended horsepower..... Because of the way The law in the united states has developed.......This is not the same for boats. BIA, CG, NMMA, and other organizations with conflicting certs actually have less control over what size engine or abilities are in any boat. Futhermore, the certificaiton process for marine equipment is still within the reach of the average backyard hobbyist. Write a few papers, document a few tests...... and your insurabilty would be as good as most manufacturers.....( I speak from experience here, several of my boats lost warranty coverage by the manufacturer going out of business). And I have found that for all but the largest or most exotic boat manufacturers. the structural modeling and analysis of their boats... is not very in depth..

and now to get to the crux of my lament

I have read or corresponded with many many people who have endeavored to upgrade the engine size on a mac, has recognized the need for transom upgrades and hull improvements, possible trailer modifications, fuel system and steering modifications and many other elements that need to be addressed in a horsepower/weight upgrade. I myself have concenterated on analyzing and providing interior hull structural modifications to stiffen the transom and hull, modifying the trailer, etc prior to installing an engine upgrade.

Now
If you want to compare here the apples to oranges....

Are the toureg and Endeavor, explorer, caravan owners out their considering what has to be done to their vehicles to provide for safer towing and handling. Are any of them contemplating installation of New frame Rails, suspension lowering and modifications, Differential or transmission gearing changes.larger springs, hi performance oil cooling systems, changes to tires and wheels..... So that their vehicles can tow 100,000 miles safely??. (Items that are already present in vehicles designed to tow large loads from the factory).

So I think engine upgrades are being addressed here on the forum correctly with respect to the actual design criteria, physical and structural limits of the materials and processes. And I do think it is possible to provide many modifications to improve the towing ability of many vehicles.....

I doubt most people are going to go do what would need to be done to convert a 50,000 dollar toureg they are still making payments on, into a long wheelbase, rwd, stiffer suspension towing vehicle. Especially since those that would typically have the aptitude, inclination and ability to do such a thing themself would probably have the techinal background and abilities to recognize the limits of each platform, and would most probably modify a more appropriate vehicle for towing.

SO I can understand the tone in writings of many of the forum's participants, both for and against any given vehicle and lest anyone feel that I am lambasting VW or mitsubishi or other midsize (Roger did put out ad copy with a Taurus towing, and after crawling under a Toureg yesterday, I feel that vehicle is better suited than the taurus) that is not the case.. ( I still own a VW and cherish that vehicle considerably).

But for considerably less money than a toureg, one could obtain a crewcab shortbed pickup, with a V8 engine, and obtain mileage in the 18-20 mpg range and still tow safely. and still have the 125" +wheel base and 5200 vehicle weight.

Because the toureg type of vehicle has considerable power at speed, (at least the mostly unavailable deisel V10, only 1500 are going to be allowed in this year, so unless you want to pay 58K, your going to get a V8 gas) the tendency is to think that it is an all perfect multiuse vehicle. But there are tradeoffs.......and the touregs profile, weight distribution, braking ability, resistance to lateral pressure, do not indicate better highway speed towing than a standard size pickup.

On the flat, fewer than 4,000 miles a year, wide roads, and little traffic passing you at 75-80 mph, keeping th mac weight below 4,000, you can probably get by with many smaller midsize vehicles...... (Which is probably 95% of most mac owners) just dont expect it to last as long towing as a full size towing rig tho.


Maybe a better title for this thread would have been ..something like..

"minimum safe tow vehicle for a 4500 llb mac and trailer for towing less than 4,000 miles a year and never up a 6 % grade more than 2 miles long.) and having the mechanicals last for 100,000 miles"

[Dimitri-2000X-Tampa]

Wow, stay away from the site for a few days and a fight almost breaks out about tow vehicles...who woulda thunk it

I would recommend some type of added stabilization (much like Dmitri has for his van) to reduce sway.

Just to clarify, I tow with a stock Honda Odyssey with relation to the suspension. The only thing I added for towing was the tranny oil cooler. As I have stated time and time again, the Odyssey is a great tow vehicle, plenty of power in the V-tec V-6, pretty stiff suspension as far as minivans go, long wheelbase, etc. What I worry about is prematurely damaging the vehicle from excess stress...not my safety over any other tow vehicle. I have also stated previously that I would rather be following behind a careful driver pulling with a class2, versus some reckless driver pulling with a class5.

But this discussion brings up another good question. Which is better, towing with a class2 (3500#) long wheelbase vehicle like my Odyssey...OR....towing with a class3 (5000#) small SUV with a short wheelbase??

[Moe]

One rule of thumb for safe behind-the-bumper hitch trailer towing wheelbase is 110" for a 23' (including tongue) trailer and 4" of additional wheelbase for every additional foot of trailer.

That puts wheelbase for towing a 29-30' total length MacGregor in the 136-140" range. That would be an extended cab/short (6.5') bed or crew cab/very short (5.5') bed pickup truck. One of several problems with truck based SUVs is that the manufacturer's cut the wheelbase severely, not to mention soften the suspension and replace the LT series tires with passenger car P-metrics.

So thinking that a 120" wheelbase is "long" is a mistake.

--
Moe

[Bill at BOATS 4 SAIL]

I tow my Mac's with a white van.
It is a well-known scientific fact that white vans tow better than blue vans.
Now, this is only in the northern hemisphere, as you probably are all aware of, except, of course, as you get closer to the north pole (about 23 miles + / -) for some reason, gray vans tow better. This is believed to be caused by the difference between magnetic north, or true north, or maybe Pasquale's Principal, or Assistant Principal.
A well known phenomena in the southern hemisphere, so possibly some of you may not be aware of it, is that the closer you get to the east pole, an orange van tows better than a blue van. However, a school bus yellow van may be the best tow vehicle. This has only recently been discovered, and there is not a lot of data on it, but they are performing scientif tests on it as we speak (type?).

[Dimitri-2000X-Tampa]

Moe, you are playing around with semantics and avoiding my question. Here, let me fix it.. The Odyssey has a long wheelbase relative to most passenger vehicles on the road (and certainly most if not all class2 tow vehicles). When will you post the picture of you towing your Mac with a Kenworth?

Like most things in life, this is a relative discussion, otherwise, why didn't you take the money you spent on a Mac and go buy an old fixer-upper blue water cruiser instead? That would probably be safer than a light weight little Mac. And I take it that your house is well constructed with solidly poured block walls with rebar throughout...with your steel roof attached solidly to the foundation, just in case a tornado rips through? While we are at it, did you order the bullet proof glass option on your truck ... to lessen the risk of a stray bullet?

In case you were wondering, I'm just joking around with ya to make a point.

[Dimitri-2000X-Tampa]

Bill, are you the one that spread that "blue hull" rumor too?

Honestly, I've been known to tow my Mac with a golf cart. One of the three major reasons I bought a Mac was because of its class2 towing. This was also apparently a design criteria too. Why make people think that you need to have a monster truck to tow this boat with?

And frankly, this whole discussion should have been in the "towing" section of this website anyway

[Bill at BOATS 4 SAIL]

Two out of the three voices in my head agree 100% with my previous post. The other four do not.
As for blue hulls being faster than white hulls, it is a known scientific fact, that blue hulls are faster than white hulls, and vice versa. At least in the northern hemisphere, while on a starboard tack, during daylight. However . . .

[Moe]

The question really is, "Which is worse, towing with a probably overloaded class II vehicle with 16-20" too little wheelbase, or towing with a more than weight-adequate class III vehicle with 32-36" too little wheelbase?"

IMHO, it's a moot point, since neither is acceptable to me.

--
Moe

[Dimitri-2000X-Tampa]

Moe, based on your comments, could you please list all the 138+ inch wheelbase passenger (non-commercial) vehicles that you know about?

Hopefully, that hold 6-8 passengers too. One of these days, I intend to buy a different tow vehicle, so I would like to know what I should be looking at.

[Moe]

Here are some 136-140" options:

Six-Passenger:
Ford Crew Cab F150-F350
Chevy Crew Cab (1500HD-2500HD)
Dodge Quad Cab (1500-2500)
Toyota Tundra Crew Cab

Greater than Six-Passenger:
Ford Excursion
Ford Passenger Van E150-E350
Chevy Passenger Van 1500-3500

(Chevy Suburban 1500/2500, a little short at 130")

Whether you need 1/2 ton or larger capacity for the MacGregor depends on whether you intend to carry a full compliment of passengers and cargo in the tow vehicle while towing.

One advantage to Crew Cab pickups with a camper shell, is that heavy, dirty, and flammable cargo isn't in the passenger compartment, especially in the event of an accident.

--
Moe

[Chip Hindes]

As I have stated time and time again, the Odyssey is a great tow vehicle

Stating something frequently doesn't make it so. For towing a loaded Mac, the Honda Odyssey is at best adequate.

Which different combination of inadequate features would you rather be behind? Would you rather be behind an indequate tow vehicle being driven conservatively or an adequate vehicle driven by a maniac? Would you choose your execution to be by firing squad, hanging or lethal injection? Equally vaild, equally irrelevant.

"Following behind" is not really the time you need to be most concerned about what vehicle the Mac is being towed by. When you really need to worry is when it's coming at you head-on from an inside curve down the mountain, when you're stopped in front of it at a red light at the bottom of a hill in the rain, or trying to pass it on the interstate in a crosswind. The prudent driver of the merely adequate vehicle can usually avoid these situations and ensure that the vehicle remains within its ability by pulling off the road or simply staying home when conditions become adverse, but how many ae prepared to actually do this? And you can't control the truly random or unexpected. What about when it hits an unexpected pothole, blows a tire or has to do a quick lane change in order to avoid some idiot pulling in front of it? Not your fault, not predictable, but it's the wrong time to find out the vehicle you're driving lacks the safety margin to recover from the unexpected.

What we've learned by anectodotal evidence, is that in a given specific set of ideal towing conditions, even a Honda Civic can work. Under most conditions, there is quite a large array of vehicles with which people have towed successfully and most of which could be termed various degrees of "adequate". There are also, unfortunately, some number which aren't much more than accidents waiting to happen.

Mac owners in general, and certainly the participants in this discussion board, seem to be the kinds of people who are disposed to "push the envelope". I submit that the tow vehicle is not an area wherein pushing the envelope is particularly wise. Much as some would like to convince others it is so, you can't repeal the laws of physics, and you might want to consider this an area in which you go for something more than adequate.

[Duane Dunn, Allegro]

Just go weigh your boat and trailer. Mine is over the 3500# rating as are most others. Don't cheat, fill the water and the gas tanks, load the normal stuff. It's only a stripped boat with a small motor that comes in below the 3500#'s. Once you admit this you will clearly see that the mac exceeds the class II 3500# hitch rating not to mention it's trailer rating as well.

You can blindly wave the Taurus / class II marketing hype from the factory all you want, but the reality is the boat needs a Class III tow vehicle.

[Jeff S]

Dmitri,

I stand corrected about you having added stabilization. It was KMclemore with a Toyota Sienna with airlift rear air suspension that I was remembering.

There is no doubt a large truck like Moe mentions will tow better than a van or other passenger vehicle- that is what it was designed to do. I think there are other vehicles however that can adequately and safely pull the Mac if loaded properly, hitched properly and driven safely. Some are better than others as many have pointed out. It seems, from the experiences here, that SUV's are hit or miss depending on the SUV.

Jeff S

[Dimitri-2000X-Tampa]

Seems like people are misunderstanding my meaning. I never said that a big truck isn't better to tow a Mac with, and eventually I will get something similar myself (I already owned my minivan when I bought the Mac and was not/still am not interested in replacing the vehicle). I'm just saying that the Odyssey van I have does quite an adequate job. It also handles well and I wouldn't be surpised if it doesn't handle better than many SUV's. Granted, I just tow short distances but I do not have these "white knuckle" experiences I read about and the trailer doesn't sway unless I go over 65. The vehicles Moe has listed are probably rated at 5 times more weight than the Mac rig. You have to take into account how often you will tow, and what kind of gas mileage you are getting, etc. My Odyssey gets 25 mpg on the highway when not towing.

[Robert]

Full size long wheelbased vehicles with sloppy mush suspensions are less safe than a properly tow rated stiff suspensioned shorter wheelbase vehicle.
..
My very own Mac26X has been towed by my Trooper with a stiff suspension (upgraded springs, sway bar bushings and excelllent shocks) and by a full sized van (5 bolt wheels) with mush suspension. The full sized van could hardly keep itself upright much less control sway of the Mac26X. The full sized van had a big sway problem and my Trooper has no sway problem.
..
So, my point is that if you are going to get one of Moe's suggested long wheelbased vehicles, get one rated as a truck, ie skip the 1500 size and go with the 2500, or at least do a 5 minute DIY suspension test on what you are considering as a tow vehicle.
..
My DIY suspension test: First go about 0.25 mph in a straight line and hit the brakes really hard, count the number of times you bounce back and forth, just once or twice is OK, many more times is sloppy. Second go 10 to 25 mph and turn the steering wheel back and forth trying to build up a bigger and bigger (resonant standing wave) dive to each side, if you can get it flopping side to side like a small boat in a big storm, its too sloppy. Of coarse this test is subjective, so try a few different vehicles, dealers love you to test drive everything anyway and see what I mean. There are some really bad suspenson vehicles out there, just be careful what you buy.
..
A friend of mine loves cars and boats, so I suggested he combine his interests and get a 1971 Caprice, if has 400hp, sucks down gas as fast as a offshore powerboat and sways pitches and rolls like a small boat in a storm, he got the joke. I had one once, you could walk up and push by one hand on the roof edge and get it floping side to side then walk away while it continued flopping as if a couple of teens were "parking" somewhere.