Tow Vehicle Characteristics

Warning, very long.
I am creating this thread as a spin off from:

http://www.trailmanorowners.com/foru...ad.php?t=12349

That thread discuses "The "Recommended Tow Vehicle" list

I created this thread to discuss the characteristics of a good tow vehicle without focusing on a particular vehicle.

I hope this thread evolves to:

1. identify and define various characteristics related to a tow vehicle this includes comfort features.

2. personal experience stories that relate specifically to these characteristics.

I'll start with, in no particular order:


Wheelbase

Distance from the front axle to the rear axle.

Longer is better, except when making tight turns.

Results in less porpoising and less tail wagging the dog.

I have towed my TM 2720 with both my Chevy 1500HD and my GMC 2500HD. The wheelbase on the GMC is longer. I can say from experience that the longer wheelbase contributes to less porpoising between the truck and TM. I would not take the GMC to the mall at Christmas.



Track

The distance between the left side tire and the right side tire.

Wider is better, because it is more stable at high speeds in turns. High speeds might be 35 mph on a mountain road.

Though I do not tow with our Lexus RX350, I can say that it rocks side to side on back country roads, because of the uneven surface. Tall narrow vehicles are more susceptible to rolling over than a short wide car. A jacked up compact truck will not corner as well as a sports car. Many years ago the Jeep got a lot of bad press because it rolled over so easily. This is not unique to the Jeep. Nearly any off road vehicle will have this characteristic because they are tall in order to have extra ground clearance for going over rocks and logs.



Distance from tow ball to rear axle

Shorter is better.

Shorter results in less of the tail wagging the dog.

I have no experience with this.


Ride height

How much distance is there between the round and the bottom of the vehicle.

Higher allows you to clear more obstacles. Lower increases stability in turns.

I routinely tow offroad. Ride height is important to me.


Tire type

P (passenger) versus LT (light truck)

P tires will ride softer, but the flex in the sidewall will be more than it is for an LT. This increased flexing, I believe, increase temperature which would contribute to premature tire failure.



Tire width

Wide versus narrow. I do not think this is an important characteristic, except for those like me that tow in the mud offroad. Wider is better. Mud and snow rated tires are also better.


Suspension

How much sag will occur when loading cargo and connecting the TM.

Stiff suspension will carry more weight, but will also result in a more bumpy ride

My Chevy was more than adequate until I started carrying motorcycles in the truck. This increased cargo weight resulted in so much sag that I could not remove the wheel from the TM front jack. My GMC has stiffer suspension and ride height so I do not have this problem.



Tow/haul mode

Changes some characteristics when engaged for towing. This is helpful.

For both my Chevy 1500HD and GMC 2500HD the output voltage of the alternator is increased and the transmission shift points are changed.



Alternator output

More is better, within reason.

My TM has a pair of batteries and there is a lot of wire in between. When I engage Tow/haul mode the output voltage of the alternator is increased to compensate for this distance. If you have no means of increasing the alternator output voltage, my owner's manual suggests turning on the headlights, which will also increase alternator output voltage.



Brake controller

There are several different styels

- time based
- cable connected to the brake pedal
- part of the brake lines wher it measures hydraulic fluid pressure
- decelerameter based

My Chevy has a decelerameter based Prodigy. It works well.

My GMC has an Integrated Brake Controller (aka IBC). I think it is the type that measures the brake hydraulic fluid pressure. I know that I like it a lot better. It is much smoother.



Transmission automatic versus manual

This is more of a personal choice. But I believe that it should be considered.



Transmission cooler

More is better.

Almost all vehicles with a factory tow package installed will have additional cooling capacity for the automatic transmission fluid. The extra stress from towing causes the fluid temperature to increase, which is not a good thing.



Cargo volume capacity.

Volume is height times width times height

I have a reasonably large volume capacity in the back seat of my crew cab. This is a good place to carry things that need to be kept cry and cool.

I have a very large volume capacity in the bed of the truck. Not only is it long and wide, I can stack things pretty high without becoming unstable.



Cargo area capacity.

Area is width time length. I can carry more in my GMC than I can in my Chevy. The bed is the same width but the lengths are 6.5 feet versus 8 feet. This is important to me because I carry either one dual rider ATV or 3 motorcycles. I can not leave the tailgate down when towing the TM.



4wd versus 2wd versus awd

4wd provides power to all tires compared to 2wd. AWD is full time 4wd. I am not sure what the difference is between 4wd and awd when towing.

If you always camp where the roads and pads are very close to flat and are paved, then there is little reason to have 4wd.

I have camped in an RV park where the roads and pads were gravel. To exit my site I had to make a hard right turn onton the uphill access road. In 2wd mode the tires were spinning. After engaging 4wd this problem went away.

I routinely camp on open forest land (not a campground) down a dirt fire road. In the Spring and Fall it is frequently muddy, as much as 8 inches deep. I need 4wd or I can not go there.



Skid plates

This only applies to 4wd.

A skid plate protects various under body components when driving offroad.

I have skid plates on the GMC. I do not have them on the Chevy. I like then because I do not have to worry about damaging my transmission or fuel tanks. If you never go offroad then this is a non issue for you.



Engine power

There is a big difference between towing on flat ground near sea level versus going over the Sierras or the Rockies. There is also a noticeable difference in fuel economy.



Diesel versus gas

A diesel will last longer, so if you will keep the TV for a long time and put a lot of miles on it the diesel may be a good choice instead of gas.

I bought my first car in 1971. I routinely drive my vehicles for around 185k miles and 16 years. Then they go to the crusher. In my opinion you want the engine to fail about the time the transmission fails and the body rots out.

Fuel cost is another aspect. I have no experience because I have never owned a diesel.


Mirrors

Strap on versus factory installed.

I use strap on McKesh mirrors on my Chevy. I have extendable factory mirrors on my GMC. I like the GMC mirrors better.



Mirror size and orientation.

I have towed with my Chevy before I bought the McKesh mirrors. The Chevy has mirrors that are wide and short. My GMC has mirrors that are narrow and tall. I like the tall mirrors better. I frequently drive in a caravan as the lead vehicle. The taller mirror allows me to keep an eye on the people behind me.



Mirror spread

What is the distance between the two mirrors.

Wider is better.

I like to be able to see the car behind me when it is driving at my speed and tailgating. I an not see a Miata if it is riding on the TM bumper, but for normal situations I can see the car behind me. I do not have a dead spot.

Some states have a law that limits the maximum width of the mirrors.



Heated mirrors

I had a problem once with my Chevy where the outside mirrors were all fogged up in the early morning. I wiped them off but they became wet again. My GMC has heated mirrors. That solved the problem. I like heated mirrors.