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Please look over this article and make comments.
You can make comments here - please edit instead of
including the entire post.
You can also send comments to Eric directly.
Remember this is not a "for me this works" kind of article.
It is to give the basics on what to look for in a towing
truck.
From: eap@everest.Stanford.EDU (Eric Perozziello)
Hi Wendy,
I've put something together. It's rather long, so maybe it would
be better off in an FTP site by itself instead of being in the
regular FAQ for your newsgroup.
I don't have much info on horse trailers, so maybe someone else
can fill in the blanks for this part.
I'd be interested in feedback from other readers, esp people with
lots of horse-towing experience (since I'm not familiar with any
special concerns about this).
If you could provide your feedback (I've tried to orient it
towards the less technical folks that might likely be interested
in more information, so it's not very technical, and sometimes
a bit "handwavy". I hope this is what you wanted!)
I'd be glad to change it, or add to it. I'm sure the newsgroup
could help "mold" it into a useful document!
Happy Trails! (Do ya'll say that over here in rec.equestrian? :^)
-Eric
Subject: Re: Trucks and Trailers
Newsgroups: rec.equestrian
Buying and operating a truck for towing
(This guide is intended for novices. Experts will recognize a bit of
handwaving :^) I've had a fair bit of general towing experience, but
only a little experience with live cargo (cows). Take these
recommendations with that in mind.
Buy New or Used?
This depends on your needs, like any other large purchase. But
keep in mind that trucks tend to last much longer than modern
cars. Also keep in mind that maintenance costs are much higher
for a truck, new or used, so be aware of what you can afford.
(For instance, my truck takes 7 quarts of oil, and 6 tires that
cost $120 each. For comparison, my car takes 4 quarts of oil
and has 4 tires that cost $30 each.)
I'll try to guess at costs, but it will vary quite a bit by
location. A new truck will run you $25,000 to $40,000 new.
A used truck can run from about $1000 to $6,000 for older ones,
on up to the price of a new one, depending on condition. Some
trends in used trucks: Expect to pay more for four-wheel-drive.
This one feature is probably the single highest resale value
enhancement. Often times, a BIGGER truck (all else equal) may sell
for less money. Generally, a 3/4-ton model will sell for more
than a 1/2-ton model, but sometimes a 1-ton model will sell for
LESS than a 3/4-ton, or even less than a 1/2-ton. The reason being
demand. A larger truck costs more to operate (and in some cases,
more to register and insure). It may be cost effective to pay more
for a smaller truck, if you don't need a big one.
Don't be afraid to buy an older truck. There have been a lot
of changes in recent years, but not all of them are good. For
instance, modern trucks are more economical on fuel, and are
cleaner burning, but at the expense of added cost, complexity, and
generally reduced power output (though power has been inching
up lately). Fuel injection is great, when it works properly.
Condition: (if buying used)
The subject of evaluating the condition of a used vehicle could
fill several articles, so I'll defer that issue. But I'll try
to give a few pointers.
On any vehicle to be used for towing,
one of the best tests you could run to determine the engine's
health is a compression test. This will give you some idea
of the care taken and the general wear on the engine.
Some other things that might tend to get "extra" abuse on a
towing vehicle: Suspension, Brakes, and Transmission/Clutch
What Brand (truck) should I get?
There really is no major difference among the "big three" for
towing trucks. Everybody has a favorite brand, and they'll
swear by it, but there is no reason why any of the three major
brands would be better suited (other than individual taste).
("Big Three" refers to Chevy/GMC, Dodge, and Ford. These
would be the most common you would find in the US.)
What should I look for in a truck for towing?
Engine:
There are a few different ways to rate engines: The most obvious
is to tell how much air the engine can "breathe" for every cycle,
measured in cubic inches. A small V-8 is about 300 cu in. and a
larger V-8 is about 450 cu in. Another common spec is "torque" which
simply tells the maximum "turning force" the engine can provide,
measured in "foot-pounds". Perhaps the most common advertising spec
is power. This is similar to torque, except it measures how quickly
the turning force can be applied. Power is measured in units of
"horsepower", which has nothing to do with equines. Note that
power does not always correlate with engine size, because smaller
engines can generally turn faster. Torque is a little more closely
tied to engine size. Rule of thumb: a larger engine will feel more
"spirited", but will also suck more gas. Only get what you need,
especially if you also use the truck for other activities than towing.
Gasoline: Generally a V-8 engine is the best choice.
(Dodge is introducing a new V-10, which should be
fine as well) Trying to tow a loaded trailer
with a typical smaller engine (6 or 4 cylinder)
is not advised (but note that some companies,
like International, produced a VERY LARGE straight-6
that would work fine. Most sixes and fours are not
designed for such heavy work.) Most people
find that the larger pickups with V-8's, properly running,
are not power-limited, but are only limited by
stability and braking ability with heavy trailers.
Of course, the larger, higher-torque V-8's will more
easily take the hills than the smaller, lower output
V-8's, but either one will get the job done.
Diesels: Older diesels tend to emit large quantities of
hydrocarbons ("soot") that your horse may not like,
but newer diesels tend to run a lot cleaner. Non-turbo
Diesels have a reputation for being "lazy" because of
the inherently slow combustion process, but diesels
are more (energetically) efficient than gasoline
engines. Whether or not a diesel is more ECONOMICAL
depends on how much you pay for gas or
diesel fuel in your area. But generally the RANGE
you can drive before filling the tank is larger for a
diesel. A TURBO-diesel will overcome the "laziness"
of the diesel, but will cost a bit more to purchase.
One final note: Some states (CA) have mandated reduction
of the sulfur content in diesel fuels. This reduction is
causing injection pump problems. Additives can help.
Transmission:
Your choice is between an automatic transmission (which automatically
decides when to change gears, and does it for you) and a manual
transmission (where you decide when to change gears, and you do it).
A couple of points here. When towing, your best strategy is to
ANTICIPATE your next move. That is, if you see you'll need to
stop ahead, start slowing down in advance. If you see you'll
need to pull a big hill ahead, start speeding up in advance. In this
instance, a manual transmission is an advantage, since your
automatic transmission only senses CURRENT conditions to make the
shifting decision, whereas you can look ahead to see what's coming
up and shift accordingly.
Automatics are reputed to be smoother shifting than manuals, so
this may keep your animals happier on the road. But manuals CAN
be smoothly shifted- it depends entirely on the skill of the driver.
If you DO get a manual, you should learn a technique called
"double-clutching". This will match the speed of the engine to
the speed of the transmission when you shift, saving wear and tear
on the clutch, the driveline of the truck, and your cargo!
Automatics are generally designed for smooth-shifting. Unfortunately
this causes excessive wear when towing. Smooth operation is
achieved by "slipping" the gears from one to the next. This slipping
implies friction, which causes wear, especially when heavily loaded.
Fortunately, there is a solution. Some aftermarket companies (B&M)
make a "shift kit" which allows you to "re-program" your auto trans.
You can specify a "smooth, factory-style" shift, a "firm, positive, low
slippage" shift, or an all-out, racing-style "bang" of a shift. The
latter is not good for towing, as it can actually cause MORE wear
on the trans, and on the rest of the driveline. But the "firm,
positive, low slippage" shift is the best in terms of least wear and
tear.
Both types of transmissions are capable of taking large loads. A
manual transmission is more efficient. An automatic transmission
(because it is less efficient) generates more heat, which is often
transferred to the engine, via the cooling system. (not the best situation
for hot days trying to pull heavy loads up steep hills). Fortunately,
it's a simple matter to install an auxiliary transmission cooler, which
will "decouple" the heat of the transmission from the heat of the engine.
Which type will be more durable depends on the type of driving you
do. Automatics are more forgiving of starting from a dead stop.
The friction associated with getting the vehicle moving is taken
out on the fluid (which should be changed regularly). In a manual
trans, this friction is taken out on the clutch. (this is why
snow-plowers prefer auto trans). But out on the road where you're
shifting between gears while rolling, the manual trans takes little
wear if shifted properly, while the auto trans uses friction surfaces
to switch gears, and will wear more.
What about "overdrive"? You can get either type of trans with
"overdrive". Overdrive is simply an extra gear where the transmission
"speeds up" the engine's output, instead of "gearing it down".
In general, you should avoid using overdrive while towing, especially
with an automatic transmission. Usually, overdrive is indicated by a
symbol on the gearshift by a "D" with a circle around it, like "(D)".
Most (non overdrive) automatics have three gears, labeled "D", "2",
and "1". Overdrive-equipped automatics will usually have
"(D)", "D", "2", "1". Or simply "D", "3", "2", "1". Or any
combination of FOUR forward gear designations. The danger in using
overdrive (in an auto trans) while towing is that the transmission
will be shifting in and out of overdrive frequently (as the load
and speed change). Excessive shifting always causes more wear.
Simply keep the shift lever on the second symbol down, not the top
forward-gear symbol, if your trans has overdrive. Overdrive is intended
to be a "fuel saving" option, so it's ok to use it when you're not
towing. Even if your trans does NOT have overdrive, sometimes it
is advisable to shift the gear selector to the "2" in order to prevent
the transmission from shifting back and forth while going up a hill.
The goal is to minimize the number of times your transmission shifts.
Axle Gearing:
Inside the axle housing of the truck, a set of gears
multiplies the torque from the engine, and transmits this torque to
wheels. (But you don't get something for nothing: As the torque
is multiplied, the rotational speed is DIVIDED. In other words,
multiplying torque by a factor of 4 means dividing the rotational
speed by 4). Gearing is an important factor in towing. The rear
axle gear ratio is usually specified as a ratio, like 4.5:1. This
means that, for every one revolution of the wheels, the transmission
had to turn four and a half times. A larger (numerically) ratio
will put more "torque" to the road, which means it can pull more
weight. But, it also means the engine has to turn faster (higher
RPM) to do this. Of course, there is a limit to how fast your engine
can spin.
When comparing the gearing between two trucks, remember that it
depends on a number of factors: A larger engine, an automatic
transmission, and smaller tire diameter will be geared with
smaller (numerically) gears. Typical numbers
are around 3.25:1 (for say, an auto trans, large engine) to 4.5:1
(manual trans, smaller engine). All else being equal, larger
numbers imply the truck will feel "peppier", but will probably
burn more fuel.
Weight Rating:
Trucks are usually rated by a capacity (half-ton, three-quarter-ton,
one-ton) which is supposedly a "payload" capacity (IE: the weight
you can safely stick in the truck's cargo area.) These numbers are
generally very under-rated - you can safely stick much more in the
cargo area. For towing, a more meaningful number is the Gross Vehicle
Weight Rating (GVWR). This number, given in pounds, specifies the maximum
total weight the truck can have when loaded (counting only the "tongue
weight" of the trailer, typically 10% of the total trailer weight).
In general, a heavier truck is better, since a light truck can be
pushed all over the road by a heavy trailer. But remember, the more
your entire rig weighs, the more fuel it takes to pull it around.
When towing a given trailer, a heavy truck will be more stable and
generally stop quicker than a light truck. One (handwaving) way of
explaining this: When you pull a trailer, your truck must be able to
bring that extra weight to a stop, BUT it doesn't get the "benefit"
of having the weight of the trailer on its own tires (since the amount
of friction the tires can provide depends on the weight put on them).
(Imagine getting your little mini-truck pushed through the red light
by the trailer with two horses!) Of course, trailer brakes help you
to stop, but they can't help you corner, and they don't help much
when the trailer tries to swing the rear end of the truck around!
Stability Concerns:
Wheelbase is an important issue for stability. Wheelbase is
simply the distance between the front and rear wheels. A longer
wheelbase (such as on a "crew-cab" truck) is more stable than a
shorter wheelbase truck, but will be harder to maneuver in the
barnyard and harder to parallel-park at the post office.
This is one reason you should not use a "jeep" to tow a heavy
trailer.
Also, a truck that sits closer to the ground is more stable,
and is better suited for towing.
One recent technological advance that is a great benefit is an
Anti-lock braking system (ABS). This is a system that prevents
your wheels from locking up, no matter how hard you step on the
brake pedal. First of all, this shortens your braking distance.
(holding the brakes just on the verge of brake lock-up is ideal
for best braking). But the main benefit for towing is STABILITY.
If you lock up the brakes on a tow rig, you can completely lose
control of the vehicle. (The trailer tends to swing the rear of
the truck around once the rear tires lock.) Anti lock brakes
prevent this condition. There are several kinds of anti-lock
systems. For instance, a one- or two-channel system may only prevent
the rear wheels from locking, whereas a four channel prevents all
wheels from locking. Many pickups only come with one- or two-channel,
but this is certainly a big advantage over no ABS at all.
Two words of caution on ABS: First, users have reported that only
the FACTORY systems work well- the aftermarket "add-on" systems
are not satisfactory. Second, some users report that ABS does
not work well in snow, since locking the wheels "a little bit"
can actually help in the snow (snow "piles up" in front of
the wheels).
Four Wheel Drive?: (sometimes written as 4WD, or 4X4)
Four wheel drive allows the engine to spin all four wheels instead
of just the rear ones. Most older trucks allow you to disengage
the front wheels. Some newer ones are "all time" 4WD. Four wheel drive
does not offer you any towing advantage, per say, but could help
you pull your trailer out of the mud, if it's stuck. Some folks
claim 4WD hurts stability, but you really shouldn't drive on the
highway with 4WD engaged. It is recommended that you do NOT use
an "all time" 4WD vehicle for towing. One fringe benefit of 4WD
for towing is that 4WD vehicles have higher "unsprung" weight (that
is, weight not supported by the suspension system) which helps
stability.
Four wheel drive costs more, and 4WD vehicles tend to
hold resale value very well, so if you're buying used, you might
expect to pay more for 4WD.
There are some 4WD systems that allow you to disengage the front
wheels from the cab, while others require you to get out of the
truck and turn knobs on the front wheels. The later tends to be
more robust but less convenient.
Hitch Type:
Gooseneck (or fifth-wheel) hitches offer the best stability for
towing, and are easier to drive in reverse. These hitches allow
the trailer "tongue weight" to be applied directly over the
rear wheels, as well as providing the pivot point over the rear
wheels. The big drawback to having this kind of hitch is if
you plan to use your truck for other purposes: There's a big
obstruction in the middle of the truck bed. Also, this hitch
will cost more. A bumper hitch will work fine for a two-horse
trailer behind a full-size pickup, provided the hitch is anchored
to the frame, and not entirely supported by the bumper.
Some guidelines for using and maintaining tow vehicles:
THE MOST IMPORTANT THING YOU CAN DO FOR YOUR TRUCK IS TO CHANGE
THE OIL REGULARLY (and don't use any additives, unless recommended
by the vehicle MANUFACTURER)
1). Install an aux trans cooler (if you have an auto trans). It's cheap,
it'll help everything run cooler (engine AND trans) and will extend
your trans life. The cost of the cooler will be repaid many times over.
Change (auto) trans fluid often- it takes a beating when towing.
2). An engine oil cooler is a great idea, if you abuse your truck.
It'll help cool the engine, and it'll keep your oil from breaking down
too quickly. (Synthetic oil is a great idea, but maybe not cost effective.
But under NO circumstances should you ever add snake-oil like "Slick-50".
It'll do more harm than good. I have a good article on this topic.
Email me for a copy).
3). Headers (replaces the factory exhaust manifolds) and dual exhaust
will help power considerably, if your local emissions laws allow this.
Your engine will run cooler, power and mileage will increase by around
10%, in most cases. A win-win situation, except for a little more noise.
4). A freeflow air filter is a must. Change it often. (Especially
in dusty conditions that horse-folks are likely to be encountering).
Sometimes you can stack two air filters on top of one another by
lengthening the stud on the carburetor (older trucks).
5). Don't skimp on tires for the tow vehicle. A good set of tires
can do wonders for your full-loaded braking distance. (tires are rated
by load, speed, traction, and treadwear. Load and Traction are the
important specs)
6). Cross the safety chains!
7). Run 50/50 antifreeze/water in the cooling system.
8). An electric fan can be mounted in conjunction with your
factory engine-driven fan (usually) if you are having problems with
overheating at low vehicle speeds. (an electric fan can be mounted
in FRONT of the radiator, pushing air towards the engine)
9). Anticipation is your best tool when towing. If you can anticipate
when you'll need to speed up/slow down, you can save a lot of wear and tear.
10). A larger alternator may be necessary if the vehicle wasn't
originally set up to tow. (Extra electrical power is generally
needed to actuate electric trailer-brakes, and (minor) extra
trailer lights).
11). Semi-metallic brake surfaces (pads/shoes) are a good idea, if
not already equipped. Regular organics are subject to "brake fade"
when they heat up.
12). DOT-5 brake fluid is also a good idea, if you tend to run the
brakes hot. DOT-3 fluid is not as temperature resistant, and can absorb
water (which will then boil in the hydraulic lines). DOT-5 is also
better for brake system corrosion resistance, for when you might
store the vehicle, etc. (a big plus for infrequently used trucks AND
trailers. You need to completely empty the system of DOT-3 fluid
before filling with DOT-5. They are not very compatible with one another.
13). Wheel alignments can be optimized to help braking. A competent
alignment shop can advise, if you tell them you are doing a lot
of towing. The vehicle manufacturer may have more information.
14). If the coolant temperature rises (going up a hill, etc), turning
on the cabin heater (yeah, I know, uncomfortable on a hot day, but...)
will increase the cooling system's heat-exchanger capacity by about 5-10%.
And remember, your air conditioning compressor sucks a few horsepower
from the engine when it's on: keep the A/C off when you need power.
15). Gasoline: If your engine doesn't "ping" on the low-octane stuff,
then going to higher octane will not do any good (unless your truck is
equipped with a "knock sensor", in which case it automatically adjusts
to the fuel).
16). Diesel: If you're here in California (or anywhere they've taken
the good stuff out of diesel fuels) it is strongly recommended that
you run a good fuel system additive. (I'd prefer "Marvel Mystery Oil"
added to the fuel tank).
17). Motor Oils: Most name-brands are good. The spec differences
between them is generally minor, with some trade-offs for different
brands. Use a viscosity rating according to your owners manual (which
should tell you what viscosity to use for given ambient temperature.)
Higher viscosity will cause higher fuel consumption. Avoid the use of
10W40 oil from any brand (except synthetics, like Mobil 1). The
use of synthetic oil (like Mobil-1) is great, but it's up to you to
justify the higher (3x) cost.
18). In general, following the "severe service duty" recommendations
in your owners manual is a good place to start.
19). Wheel bearings (tailer and tow-vehicle) can often be overlooked.
Be sure to keep them full of CLEAN (esp for farm vehicles!) quality
grease. (drive-axles are often lubricated by splash oil from the
gearbox). Dirty, under-lubed bearings will wear out quickly and create
extra drag.
20). Watch those tire pressures carefully. At lower (towing) speeds,
tire drag is dominant. Proper inflation pressure will ensure long tire
life and reduced drag (more MPG, more power to the road). Check often,
it can't hurt!
21). If you're hooking your truck up to an unfamiliar trailer (or
vice-versa), be sure the ball/hitch size is correct. An undersize
ball could allow release of the trailer when you least expect it!
I'm sure there are some "horse-specific" towing considerations that
I've missed.
Anyone like to add any....?
-Eric (not a regular reader over here- email me at eap@everest.stanford.edu)
--
Wendy
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