by Mike "Doc" Cobine corvettedoc@geocities.com
There is always the struggle of whether to drive or tow your Corvette. This is not about the merits of either, but simply some information about towing that will be helpful so that you can tow safely. The primary purpose of a towing rig is to get your car and all of your gear to and from the place you are going. It is nice if it is comfortable, is pretty and attracts attention, and is nice with homey surroundings at the show or race, but all of this is a waste of time and money if you end up sitting on the side of a road halfway there or if the rig breaks and the trailer goes off into a ditch or into another car. Equally so, your trip is ruined if you find it stops about halfway inside the car in front of you. Read all of this carefully before you buy anything and consider that you are driving potentially anywhere from 8000 lb. to 15,000 lbs. down the highway at speeds of 65 mph. This is not like driving the Corvette or some 2500 lb. import car. This is serious business and should be approached that way.
You need a trailer that is capable of hauling at least 4000 pounds. If you are racing or autocrossing, you may be hauling more than just the car. For example, tires and wheels, fuel jugs, and tools. You may wish to add air compressors and generators and that means more weight to haul. A single axle trailer is far too light and can be far too unstable to haul a Corvette on so consider only dual axle trailers, no matter how good the deal is on the single axle.
Terms you need to clarify when buying a trailer are trailer length, trailer weight, and trailer load. Usually, a trailer is described as 15 foot, 25 foot, and so on. This refers to the bed length, not the overall length. A 15 foot open trailer will have a bed that is 15 foot long and a tongue on front that adds from 3 to 4 feet, making the overall length 18 or 19 feet. This is important to know so you do not exceed length restrictions in some states and when you are checking the room for storage of the trailer. Many people advertising a used trailer will mistakenly use the overall length.
The trailer weight is the empty weight of the trailer. It is not the Gross Vehicle Weight Rating (GVWR). The GVWR is the maximum weight of the load and the trailer combined.
The load weight of the trailer is the amount of weight the trailer will hold. This is different from the Gross Vehicle Weight Rating (GVWR) which is the total of the load and the weight of the trailer combined. A trailer with a GVWR of 5000 lb. can hold a 3000 lb. load if the trailer empty weighs 2000 lb.
Enclosed trailers have the advantages of being an extra garage. When you are not racing, showing or whatever with the car, you can leave it inside where it is protected from prying eyes, kid's tricycles, and the weather. It also offers this protection on the highway and at motels on the way. You also find that all extra gear and tools you take can be stored inside and not take valuable space inside your tow vehicle.
Whether you chose electric brakes or hydraulic surge brakes will be a personal choice. Each have advantages. Surge brakes require no power from the car so can be hauled by different vehicles easily but only work going forward. If the car brakes fail, the surge brakes cannot be activated to slow you down. They must be pinned to prevent activation when backing the trailer uphill. Electric brakes will work like your regular brakes and can be used separately in the event of a brake failure on your car. They are more complicated and require an electric controller to be installed in the car. They also require a connection to the car wiring and they require a separate battery in the trailer to make the break-away system work.
With an open trailer, you will need typically either the 500 lb or 750 lb bars. With an enclosed, you will need the 1000 lb bars. You may wish to use the sway prevention slider bars. These attach to the hitch and adjust the tension on a slide to keep the trailer tracking straight rather than swinging back and forth. Much sway is caused by too much weight is in the rear. Some sway is caused by tow rig combinations in that the length from the ball to the rear axle of the tow vehicle is very long and induces sway. Older Suburbans are typically known to have this problem.
The ball is very important as it is the only thing that keeps your trailer hooked to the car. Balls come in three main sizes of 1-7/8, 2, and 2-5/16 inch diameter. You need a 2 inch ball for most open trailers and the 2-5/16 ball for most enclosed trailers. A 1-7/8 ball is for utility and small boat trailers and will not handle the weight of a car trailer and car. The balls also come in various weight ratings. Be sure that you check the rating, stamped on the top of the ball, to be sure it is larger than the load and trailer weight. If not, the ball could break.
If you are hauling multiple cars, such as some very long trailers, the need for three axles is quickly evident in the weight that must be handled. Most trailers are manufactured today with these thoughts in mind and few will try to get by cheap with inadequate weight handling.
The big thing is having the weight where it should be to start with. With some trailers, you have enough room to move the car forward or backward to get the weight set. You want to have about 10 to 15 percent of the total weight on the tongue and hitch. Check with the trailer manufacturer or manuals to see what they recommend first. If that information is not available, use the 10 to 15 percent value.
With a Corvette on an open trailer for a total of 4500 lbs, you need 450 to 675 lbs on the tongue. With a Corvette in an enclosed trailer for a total of 6000 lbs, you need between 600 and 900 lbs on the tongue. You can also see this is not a job for a lightweight tow vehicle.
Too much weight can make the tow vehicle sway and lift the front wheels so that steering and braking are affected plus possibly straining the capacities of the hitch. Too little weight can make the trailer fishtail and cause severe handling problems at any speed over a crawl.
There are a few ways to determine how well you have the weight balanced.
First you must find a public scale and weight the trailer with everything inside that you normally haul. Then you have a total weight. After that, get a scale to read the tongue weight. You will have to disconnect the tow vehicle from the tongue and have the trailer level to read it accurately. Then move the car and equipment to where the tongue weight is in the 10 to 15 percent range. Mark where the car is located and hook the trailer back to the tow vehicle without the equalizer bars. Measure how high the hitch is from the ground with the trailer connected and this will be a good guide that you are close in future loading. Then use the equalizer bars to pull the trailer level again.
Another method is to estimate the weights. You should know the weight of the car and the trailer empty so you can use a bathroom scale to weigh everything you put inside or on the trailer. Then you will know the approximate total weight. After that, use a lever and a bathroom scale to find out the weight on the tongue where the ball hooks up. The typical bathroom scale is 300 pounds capacity so a 3:1 lever can give you up to 900 pounds of tongue weight. A 4:1 lever gives you 1200 pounds to measure. After setting up the lever and scale, move things inside or on the trailer to get the weight to the 10 percent value.
If you do not have a scale, measure how high the tow vehicle hitch is from the ground. Hook the trailer to the tow vehicle without the equalizer bars. Measure how high the hitch is from the ground with the trailer connected. If it is more than a couple of inches lower than the empty height, move the load until the height is only about 2 inches lower. This will be a fair guide that you are close in future loading. Then use the equalizer bars to pull the trailer level again.
If after you use any of these methods, you experience any swaying of the trailer, first check that all tires, axles, and hitch connections are good on both the trailer and the tow vehicle. Then try moving the car forward or backward slightly on the trailer to eliminate the sway. When it is eliminated, mark that spot and use it in future loading.
The first method is by far the best.
Tires come in various ratings. You should stick with a trailer rated tire of a heavy load range. These are designed to haul heavy loads on the open highway. Using passenger car tires is a poor practice and one that frequently finds the owner on the side of the road with a shredded tire. Be sure the load rating of each tire is the same as the weakest link in a chain still holds true. Also, be sure that the maximum load rating of all tires is much higher than the load you are hauling. For example, if you have a 1500 lb trailer and a 3000 lb Corvette, you have 4500 lb load. The tires must be 1200 lb rated each to handle it and they will be stressed almost 100% so tire failure is probable. It would be much better to have a 1500 lb tire rating as this is a 6000 lb capacity and gives you a good margin of safety as the tires are at only 75% of their maximum capacity.
Some older trailers used mobile home axles and tires. There is basically nothing wrong with this, as many have done so very successfully for many years, but you must keep the tires inflated to the full value and not run them low to soften the ride. This is true for any tire, actually. If you have problems with the Mobile Home tires, as indicated by the MH in the size, you can get a Load Range F Low Boy tire that fits those rims. This tire is designed for highway usage and long hauls and will hold up to the use on a car trailer much better.
Straps should be tight and connected so they do not pop off from the car bouncing. Pull them tight enough to pull the suspension slightly tight. You should have a strap at each corner of the car, connected to something solid such as the frame down to a solid mount on the trailer such as a crossmember or a properly installed tie down ring. The strap should be between 30 and 60 degrees angle to the floor. Do not tie the car straight down as you need to support the car from forces forward and backwards. Each strap should go from a point on the car outward to the trailer, so that they are 15 to 45 degrees to the axis of the car. These angles are not hard and fast rules but general enough that the main concern is not to have straps straight down or straight back.
Some tie down companies are making tie downs that strap over the tires and to the trailer. These are very good for light, delicate vehicles like Model T Fords or Formula Fords and Continentals, where connecting to the frame of the car and pulling tight is hard to do or would damage the frame.
See below about trucks and rentals to figure out if you want to even bother.
Unfortunately, CompuServe's format does not lend itself to going back and seeing messages that are months or years old, as there was a long discussion of all the pro's and con's of this about a year ago there.
Many are stuck with vehicle restrictions due to apartment rules, parking limitations, etc. and so they have a daily car and can't have a tow vehicle. Most daily cars today are extremely poor as tow vehicles, unless you use a Suburban as a daily driver.
The best bets are to get a separate tow vehicle, one set up to handle the load of the trailer (even as light as this FF will be) and also handle the chores of hauling your tools, spares, and race gear. It sounds simple at first, just hauling a race car to the track, but as time goes on, you add spare parts, tires, rain tires, gas jugs, tool boxes, bigger tool boxes, lawn chairs, awnings, car covers, jacks, stands, and so on.
This brings you to things like older full size station wagons (no new ones built anymore), SUVs, vans, pickup trucks, motor homes, and such. What you get depends on your needs and budgets.
Typically, people get SUVs to use as daily driver and occasional tows. The SUV will work on a light car like the formula cars and even on some light sedans like IT race cars, but on larger cars, like a Camaro or Corvette, the typical SUV is not built heavy duty enough.
The custom vans with bay windows and extended roofs are typically poor tow vehicles except for light loads, since the custom interiors are quite heavy and use most of the load rating capacity of the van. One should work fine with a FF and light trailer, but would be more strained with a dual axle and an A/S Camaro or a stock Corvette. Most suffer from lack of interior room to store large items like tires, tool boxes, and spare parts. the extended roof versions do make a nice area to spend the night and give room to easily change in and out of a drivers suit. with addition of helper springs, these can tow a Corvette on an open trailer, but they should be avoided if attempting to tow an enclosed trailer unless they are ordered new to do just that.
Cube vans - typical known as commercial vans and delivery trucks. These have lots of room and can be set up as a permanent storage and shop for the tools, gear, and even the FF. Problem in some neighborhoods as they look commercial. They can eliminate the need for the trailer, tough. Typically these have at least 1 ton ratings and are geared to haul heavy loads.
The first choice is easy, you need a V8. Under the right conditions and the right vehicles, you can get away with a V6 but you are limiting yourself in many ways. The next choice is size. If you plan on driving this vehicle daily or even often, a 350 cid is not a bad choice. It can haul a large trailer and still do so reasonably. If you are only into long hauls across the country, and you are not into driving this vehicle every day, then move up to the 454 or 460 as they will be more at home on the long highway hauls. You can also consider the diesel engine options. They offer lots of power and good economy, which is not part of the 454/460 option. They are sluggish and don't have the snap most are used to with a gas engine, but they do have advantages of long life, good economy (relative to hauling trailers) and very good power. Opinions of fellow racers are that the new Dodge Cummings diesel is perhaps the best with Ford second. The GM/Chevy diesel is considered a poor third.
If you buy used, as most racers do, check for this equipment on any prospective vehicles you examine. If it is not on the vehicle, consider adding a transmission cooler, oil cooler, helper springs, airbag springs,, heavier alternator, and heavy duty flashers. If the radiator is marginal, consider replacing it with a new or a slightly larger (if factory available) size as towing and fighting overheating engines can ruin any trip.
Bigger U-Haul/Ryder/Hertz/etc trucks. Depending on what you find, many will handle a FF inside, so you don't even need the trailer if you figure out a ramp system. They provide all the shelter and room for tools, storage, etc. About double the pickup, but still roughly only $600 per year.
A lot to consider and one that only you can decide.
Remember, the one purpose of a tow rig is to get you, the race car, and gear to the track and back. If you have to worry about it doing that, it isn't right. If it fails to do that, it isn't good.