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 Dear
Andy:
We are interested in purchasing an RV (30 foot category).
Originally we were looking at a traditional tow trailer
since we were told that it was unlikely that our truck (2002
Dodge Ram, 4.7 liter, with towing package, crew cab, short
box) would handle a fifth wheel of that size. Apparently
the tongue weights of 1400 - 1500+ pounds are too heavy.
We went to another dealer and we were told 1) that there
was no trouble towing a fifth wheel (tongue weight of the
trailer in question was 1540 lbs) and 2) that tow trailers
were a lot more difficult to handle on the highway, especially
when being passed by trucks and we would find that there
would be a lot of tension (on the driver) pulling one of
these trailers. I plan on towing this trailer for thousands
of miles and I don't want to end up a basket-case by the
time I get there.
We returned to the original dealership and discussed
this subject. We were assured that there was nothing to
be concerned about if the trailer was hitched properly and
that their customers have not experienced any problems.
We have since talked to a friend of ours who has towed
both types of trailers (25 footers) and he said he would
never buy another trailer unless it was a fifth wheel. He
said he didn't like to take his tow trailer as far as Orangeville....we
are looking at towing the trailer to Arizona!
I am truly confused and concerned by the two different
stories I am getting from the dealers. We are looking at
spending $40,000.00+ and don't want to make a big mistake.
I also don't want to damage my truck by overloading it.
Can you please help me out?
Regards
John Parker (Page Top)
Hello John,
There are advantages to both the trailer and fifth wheel,
the important thing is to make sure the Travel Trailer is
connected properly. When a fifth wheel hitch is installed
as long as the installer manages to get it over or slightly
ahead of the axle on the truck then the fifth wheel is likely
to tow pretty well, in other words there is not a great
deal they can do wrong with the installation. Installing
a hitch for a travel trailer is an entirely different matter,
it is not extremely difficult but it is often not done properly.
In earlier issues we have gone over this in detail and we
can send you a reprint of the article.
On a truck such as yours a fifth wheel has no substantial
towing advantage over a properly connected travel trailer.
Having the pivot point located over the axle instead of
behind certainly helps but it comes at the price of a much
higher center of gravity and the pivot point between the
units is about 45" off the road instead of about 20". Straight
line stability will be slightly better with the fifth wheel,
the trailer will be better in emergency maneuvers and have
a shorter stopping distance. With the addition of a hitch
(such as a Hensley Hitch), the trailer will actually tow
better than the fifth wheel but it would not be mandatory
with your truck.
Your truck has a rear axle capacity of 3900 lbs., by the
time you fill the fuel tank and install a fifth wheel hitch
you will have about 2100 lbs. on the rear wheels, leaving
about 1800 lbs. available for the pin weight of the fifth
wheel so a 1540 lb. pin weight sounds OK. I would want to
take the fifth wheel trailer to a scale and check the pin
weight. Occasionally models get refined, options get added
and the pin weight can change by three or four hundred pounds
without getting changed in the brochure. This is not a big
factor if you have a 6084 lb. rear axle but with a 1/2 ton
you do not have the leaway.
Fifth wheels have a large storage area under the goose
neck and often most of the storage inside is forward of
the wheels, so it is not hard to add 500 lbs. of load to
the pin weight which puts you over 2000 lb. and overloads
your rear axle. Rear kitchen models tend to maintain their
pin weight better than a rear living room does. If you carry
anything in the box you may further overload the rear axle
of the truck. So it would be conceivable for you to be carrying
4300 lbs. on a 3900 lb. axle. Often people who already own
a 1/2 ton will purchase a fifth and tow it for a couple
of years until they get a new truck, I know many people
who have gone thousands of miles with a slight overload
situation and have never had a problem but it sounds like
you plan to keep your truck for the long haul and who can
blame you, itŐs a nice vehicle.
With a travel trailer weight carrying is not a big issue
as hitch weight is usually down around 800-1100 pounds on
a loaded 30' trailer and you will be using an equalizing
hitch to distribute it over the front and rear wheels of
the truck. Usually a trailer will have less aerodynamic
drag, even a trailer the same height as a fifth wheel will
have less drag. I think it is because air is not being trapped
under the goose neck. Maneuvering is easier in some instances
with the trailer as it will not track in as far in on tight
turns or when getting into a campsite but the overall length
of the combination is longer. The lower height often helps
getting under branches etc.
I hope this gives you some facts to help you with your
decision. (Page Top)
Dear Andy:
Love your magazine, especially the technical stuff.
In May I purchased a new GMC 2500HD crewcab with the
diesel option and a Titanium 32E37DS. I note a fair amount
of bounce when I go over any undulations in the highway
and was wondering about the shocks. I looked under the fifth
wheel and although there are four shocks there, they look
pretty skimpy and I would question the angle of mounting
also. My truck is as it came from the factory. What would
your recommendations for both the truck and the fifth wheel
be?
Cliff Britch
Hi Cliff:
You have a problem opposite to John. Your truck is heavier
than you need for your trailer. You have a 6084 rear axle
capacity and likely have about 4500 lbs. on it.
If you look at the rear axle on your truck I think you
will find that there is a thick helper spring under the
main stack of springs. When the truck is empty there is
about 1" of clearance between the ends of this helper spring
and the main stack. This is so the truck rides reasonably
smooth when empty or lightly loaded.
If you lower the fifth wheel onto the truck and watch the
springs you may find that the fifth wheel is heavy enough
to settle the main stack onto the helper but not heavy enough
to bend the helper spring very far.
This sets up a stiff ride in the back of the truck. With
the length of the trucks wheelbase and the flex in the chassis
you do not feel it in the cab but the front of the fifth
wheel sure does and it sets up quite a bounce in the back
of the fifth.
The solution is relatively simple. A spring shop that normally
re arcs worn springs can put a reverse arc in the helper
springs. This will give the main stack more travel before
it comes into contact with the helpers. It is quite amazing
the difference this makes and you should notice it right
away.
(Page Top)
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