more on wheelbase

[rangebowdrie]

recently i was looking at some older posts on towing issues. some talked of effects of longer or shorter wheelbase lengths on the stability of the tower,and the towee. others spoke of the ability of some makes of hitches to shift the center of effort forward to more closley mimic the dynamics of the fifth-wheel type. the mention of "polar moments" was getting into sound physics. yaw charicteristics of the trailer try to force the tow vehicle to rotate around a verticle axis. this rotational force is conteracted,we hope, by the "moment of inertia" of the tow vehicle. we can easily demonstrate this effect; hold a 12"ruler in the middle of your out-streached hand, and twist it back and forth quickly, now do the same with a yardstick. this is why long-haul truckers drive the longest wheelbase tractors they can get. in the old days,before crew-cab pick-up's, the suburbans could haul the family in comfort, with some luggage in back, a medium-weight airstream in tow, and head off on adventure. with it's good weight distribution, and reasonable wheelbase it works well. however, with the weights of trailers and the seeming endless amounts of "junk" we all think we need to take with us, a long wheelbase crew-cab pick-up goes a long way towards stability, and room for people and "stuff".

[slowmover]

I'd like to see statistics back up the comment about big rig tractor wheelbase being a safety factor. A 60,000# load isn't going to be "stopped" by a longer wheelbase tractor. I've looked for but never found that attribution.

Comparing big rigs and RV's is bad business, they don't compare well enough.

As to RV's, there may be a reasonable wheelbase limit, but I doubt it is the one put about by rv.org and others.

Cars towed trailers in the vast majority in the 1950s thru the 1970s. I have asked for, but no one has provided any attribution that they were less safe.

They may have been better, all other things being equal.

[rangebowdrie]

yes, cars did do most of the towing in the old days. trucks back then only held two people in discomfort. a lot of the family sedans back then had big-block engines with the horsepower to pull trailers, and comfortable for the whole family. what they lacked was good brakes,good suspention,good transmissions,good radiators,and good electrical systems. no thanks, the newer rigs are light years ahead.

[2airishuman]

sorry lovers of the good old days...

but 50-70s cars were and ARE unsafe for multiple reasons...

this issue has been BEAT 2 death and the evidence presented so many ways already....

we've got 30 YEARS of data and reports and explanations about the dangers of vehicles from that era.

lap belts only, non collapsing steering columns, metal interiors, no head supports, no crumple zones, poor brakes, lack of abs, inadequate lighting...

bias ply AND radial tires were CRAP 30 years ago...

COME ON the list is long and the issues well documented.

on the towing side speeds were MUCH slower, roadways LESS crowded, commerical truck traffic was 1/4 of the current level and on and on and on...

the typical 1/2 ton pick up truck was basically the equivalent of the cars (in capacity) only with a truck bed and 2 seats as the difference.

and the pick up trucks of that era (50-70s) were even LESS safe than the death trap cars....

sure it is nostalgic and comforting to 'think back' but NOTHING was safer about automotive travel or trailer towing in the 50s, 60s or 70s...

i can remember having fun riding in the back of open trucks,

or sleeping in the rear window of a big impala or dodge,

or poking a stick down through the rusty HOLES in the rear seat floor boards of the buick and the ford...

but NONE of that stuff and NONE of those vehicles were safe...

we're all lucky to be alive and to have survived.

and besides, the air conditioning and radios were pretty crappy then too!

cheers

2air'

sure some are happy with their fully vintage set ups and a.m radio, for a weekend outing or a 2 month cross country walk/jog...

but those folks ALL know the key is going slow, not pushing the vehicle or trailer, and thinking about the parade!

cookie, cookie lend me your comb!

[CanoeStream]

My wife's first car was a late Ford Falcon with a 289 -- the engine blew in Muskogee, OK, Labor day of 1974. (oh really?) The Mustang was nothing but new sheetmetal on a Falcon chassis -- a lot of cool factor but not much for suspension. I could imagine a Caravel behind.

Lobbied by the US auto industry, Congress passed the Federal-Aid Highway Act of 1956. I recall a mixed network of a few 4 lane highways in the early '60s. All other roads were 60 mph and two lanes. Towing speeds were not high. TV-trailer combinations could get by with more borderline setups compared to the days of 70 mph. Oh wait ... guess they didn't have Marathons. Should that be 65 mph?

[Silvertwinkie]

I'd have to agree with what has been said so far.

In addition, if the question I extrapolated from REDNAX was why was it better to tow with cars in the past compared to today, I think the answer is fairly simple:

Cars of the '50s, '60s, '70s and somewhat in the '80s had the equiv of what was/is a 1/2 ton truck in terms of engine, transmission, body on frame construction, etc. That didn't make them a better solution of the time, as has been pointed out, but comparing cars of yesterday to what's on the road today, if I had to, I'd tow with the likes of a 1970 Cutlass with a 454 engine or even a 350 over a front wheel drive vehicle or a unibody vehicle.

Another thing to point out is that Airstreams (and possibly to a similar extent SOBs) of yesteryear, when these kinds of vintage cars were tow vehicles, had far less weight to contend with than today. From what I understand, it's not uncommon for a vintage Airstream to weigh significantly less than the units of today. If you ask the question, well how could that be, take a look at the inside of say a 50s, 60s and 70s Airstream (not modified), then take a peek at a 2008. You won't find big screen TVs, microwaves, high capacity grey, black and fresh tanks, 60 to 80lbs of LP, two door fridge/freezers, dual batteries, heavier frames (to deal with the added interior weights), etc.

This is why, IMHO, towing a vintage trailer with a vintage car was possible and so commonplace. Lighter weight RVs, and basically 1/2 ton (or in some cases even more robust) cars towing them. This is totally different to what is on the road today. Far less robust passenger cars and way heavier RVs. That is why so many folks here on this forum alone say go with a truck, not a Mack truck, but a good truck that matches the application (1/2 ton, 3/4 ton, 1 ton)...you can't find that in the passenger car lines of today, since 1996 from GM for example.

[rangebowdrie]

your'e right on about the changes in the traffic density and speeds today, compared to yesteryear. and trailer weights too. the old '75 28ft. overlander had a GVW of 6200lbs.,and todays 28ft. safari is pushing close to that with just some water and a cast iron frying-pan. i recently checked-out a '75 31ft. soverign, it only had a frame that was 3" in depth, it also had about 2 to 3" of frame sag in the rear. but i suppose rear frame sag is a whole other issue.

[Rodger with a D]

Hola There

The 1965 MotorCade Magazine did an test with an four door family sedan that was not an factory OEM Tow Vehicle. All they did was to install an Trailer Brake Controller, The Light Plug, and had the Mfg'r Spec'd hitch to the frame. The car was an "unibody" with the standard issue rear axle ratio.

The test trailer was an 1965 4300 pound OverLander.

They found out the car could not get the package over 93 MPH, but as an package, the package stopped shorter than just the car.

Hmmmm,

Rodger & Gabby
COS

[Ahab]

Yes, I think a longer wheelbase helps stability in towing. We had a '98 Exploder which was not bad as a TV but when we got the Honda Ridgeline the difference was remarkable.

[slowmover]

Since I only recently quit driving a 1971 Chrysler I have a pretty good handle on car performance then, and truck performance now, having just moved up from a 1/2T Dodge to a 3/4T Dodge.

The Chrysler (Newport) was both longer and wider than a Suburban, but had a shorter wheelbase at 124". With driver, full fuel and 50# of stuff the car weighed 4,780#. The brakes and rear axle were the same as the 1/2T Dodge of the era, as was the drivetrain. But the torsion-bar front suspension and overall engineering of the chassis/steering was such that I could:

out-brake
out-accelerate
out-handle

any contemporary Suburban, as well as achieve the same or better fuel mileage. As the driver as also in a lower plane, and a little over five feet back from front axle center, the ride was incomparably better.

My 1/2T truck was a pig in comparison, BUT it could haul a very heavy load by comparison; it weighed (same as above), 5,280# but was severely deficient in power by comparison.

The Cummins weighs over 7,000# and is the worst-handling, worst-riding, worst-braking of the bunch. It can, however, carry over 2,200# in the bed. Etcetera.

My point in the second post of this thread was that it MAY be that the cars were better in many respects. Take a deep breath, 2Air, I am not advocating the purchase of a 40-year old car to anyone. On the other hand, some of your "citations" are flawed, I can provide plenty of examples to counter them. Todays vehicles ARE better, granted, but not always in ways that preclude the older ones, versus, say, a car from the 1940's.

Todays trucks are NOT advanced in any significant way from a 1960's full-size passenger car, only incrementally are they better. The inclusion of stability/braking controls and airbags is about the one fundamental difference in safety (under the control of the oem car makers, unlike tires).

A 600-mile day in that old Chrysler was better than ANY 300-mile trip in a Suburban for safety and being rested.

[2airishuman]

Originally Posted by REDNAX

]...They may have been better, all other things being equal.

so it appears 'equal' means something other than equal.

and it reads like the comparison is now apples and redebaga...

so now the 'equals' are a chrysler newport and a suburban or a dodge ram diesel?

it's pretty well know that the big modern suvs and trucks have issues...

-poor head/neck protection, roll over issues (especially with oversized or low profile tires), stopping distances and...

damage inflicted on others.

only recently has the steering and suspension and restraints and 'safety' of a burboun progressed much.

and the same is true for 3/4 ton trucks (all 3 still have HUGE injury and safety issues)

but they do make good towing rigs for large trailers and modern cars do not...

so is the modern big truck the design sequel to 60-70s cars?

perhaps, since about nothing else is body on frame, leaf spring, straight axle anymore.

we've already determined a modern honda minivan can WHIP a vintage jag on the track, it's a fun comparison but only entertainment...

what's next newport vs ram races?

IF you think the safety comparisons of modern cars with 40 year old cars is flawed...

tell us how, it might be interesting reading.

there are LOTS of creative rig combos in the a/s world, and it's lots of FUN to see them on the road or at the rallys and shows.

but that has nothing to do with the simple reality that modern cars are much much safer (and cleaner) than vintage cars...

and modern trucks are stronger than old trucks

and modern a/s are heavier, wider and full of new gadgets compared to old airstreams...

but it's fiction to suggest anything is 'equal' when picking 2 vehicles from different eras and different product lines and all the other things that make 2007 different from 1967.

cheers
2air'

it' would be great fun to have a new, long bed crew cab 2wd diesel truck, and LOWER it about 6-8 inches....

we could even do a car shaped body kit, in say a continental or imperial style!

[slowmover]

2Air, then and now, driving skill plus rigorous maintenance make the difference. Add to that buying a quality car and using the same or better parts than the factory provided. And, upgrades (like Koni shocks).

We had plenty of cars that still had compression within spec at well past 100,000 miles; cars that didn't need brake jobs for 70,000 miles of combined driving, etc. And that pulled 6,500-lb to 7,800-lb trailers all over the country. Slowly, perhaps, up Wolf Creek Pass, but with no problem on the downhill side either.

I remember climbing some grades at wide open throttle in second gear for more than twenty-minutes. (The real reason to stick with a Chrysler drivetrain).

I don't miss 8 or 10 mpg towing, or the short range. That's about it. I wish we knew to go for a Reese Dual Cam, it likely would have been a better choice.

AND those cars were far better than any modern pickup/Suburban for solo driving.

I still feel that a good minimum for towing is 4,000-lbs and 120" wheelbase. Safety statistics bear out that this is optimum for passenger safety in all driving.

Beyond that I have yet to see a correlation. Wheelbase increases likely drop off at some point in the "stability" curve.

WHERE it does so for towing I'd like to know.

(And if either of us win the lottery then we can bang heads and fabricate a diesel tow vehicle that, perhaps, encapsulates the virtues of an A/S in a tow vehicle: independent, stable, aerodynamic).

[safari 28]

This is getting off the subject of wheelbase but the past reminds me of real quality issues and long lists to the dealer to get things right. Fast forward to present and a new 08 f150 off the lot, hooked to a 28 safari, towed over 7900 miles and not one thing wrong.NOTHING! The oil did not even move on the dipstick. I had it changed and thats all at 5k.

So the good old days were well not so good in my opinion.

[Ahab]

Originally Posted by REDNAX

Todays trucks are NOT advanced in any significant way from a 1960's full-size passenger car, only incrementally are they better. The inclusion of stability/braking controls and airbags is about the one fundamental difference in safety (under the control of the oem car makers, unlike tires).

A 600-mile day in that old Chrysler was better than ANY 300-mile trip in a Suburban for safety and being rested.

Whoa there pard, I don't think you are aware of the great strides all the makers have made in todays trucks. I had one of those 60's Chryslers.

[slowmover]

I have one of those trucks, see signature. It's my second "modern" truck in the past few years.

[Druupy]

Stabillity(in a tow vehicle) = the resistance to trailer induced sway.

Hensley arrow - geometric hitch perfection.
It works by making the trailer think it's a fifth wheel.


For all the other folks, that use a "bumper pull",
the most important thing is side wall stiffness of the TV tires.
This is(are) the point(s) where the TV resists the induced sway.

The second thing is Ratio of over hang to wheelbase.
Most pickps have 4' overhang.
That is the distance from the rear axle center to the hitch.
120" wheelbase with 48" overhang,
you get 2-1/2 times the leverage to resist sway.
140" wheelbase you get almost 3 to 1 resistance
160" wheelbase you get 3-1/3 to 1 leverage to resist.
But, only if you have the proper air pressure and tire sidewall stiffness.
The rear TV tires are the fulcrum of all induced sway, not the ball/hitch.
Now remember that one of the members stated that his Astro van was one of the finest TV's he had ever driven. That is due to the extreame short overhang. Less than 3'. so, An Astro with 120" wheelbase and 36" overhang,
will tow and be as stable as a quadcab longbed, ratio 3-1/3 to 1, but much easier to park.
So Why is a Tahoe a poor TV, Fluffy tires for a good ride and 2-1/2 to 1 ratio, not enought resistence to sway.
Twitchey, scarey, don't lose focus, ever.

So for fun, put your gloves on first, go grab the towball and push it left and right. Get in to the frequency of the TV, try to make it sway. If you can make your TV move more than an inch either way, you have a problem.

Trailers don't sway, they only go where they're towed.

So, does anyone remember the way to test shocks?
You stand on the bumper, step off, and if the vehicle rebounds more than once, your shocks are bad. Same thing with the towball, if your vehicle wiggles to readily, it is gonna sway to much.
And you can test a TV before you buy it.