Hitching Up

Hooking Up

Next to a utility trailer a Boler is probably one of the easiest trailers to hook up. It is preferable to have a second person to guide you, though not necessary.

If you are alone and have a wheel on the jack stand the trailer is light enough that it can be moved a couple inches into position by the average person, I move mine around with the solid pad.

Some use the two board method to judge the position of the tow vehicle. Back in until you are close but still have about a foot to go, get out and survey the situation, lay a board across the ground to stop the tire at the required spot, if you have to move sideways lay another one along the ground the required distance away from the tire. Pull forward and slowly back in along the one board until your tire just touches the second board.


You will require a receiver hitch on your tow vehicle, fortunately the Boler is light enough that either a Class 1 or Class 3 hitch will work, this will be determined by the towing capacity of your vehicle. The minimium recommended by the Boler manual is a Class1 with a 200 lb. tongue weight and a 2000 lb. trailer weight capacity. A Class 1 hitch has a 1 1/4" square receiver opening, a Class 3 will have a 2" square opening. In addition you will require a ballmount and a 1 7/8" diameter ball to fit a stock Boler hitch. Ballmounts come in different rises or drops to position the top of the ball at the required height, for a stock Boler with 13" tires you will want this height to be 16". This measurement may vary due to modifications done to the trailer, try to get the trailer frame level or nose slightly down, if the trailer is towed nose up the trailer may be more prone to swaying.

This ballmount drops the height of the ball by 3 1/4", notice how the safety chains are fastened so they cross each other.

You will also need a wiring harness installed on your tow vehicle, the two most common plugs are the "4-Way Flat" and the "Seven-way plug". The "4-way Flat", which will likely be the type installed on the trailer, will be adequate unless you have electric brakes or wish to charge the coach battery while towing. For future convenience many people install the "Seven-way plug" and either use an adapter to connect to the trailer or change the plug on the trailer. This is why it is a good idea to inquire about the type of plug on any trailer that you are picking up sight-unseen. For wiring instructions see this page.


Load the trailer so the weight is balanced, from side to side and end to end. Take into account extra weight that may have been added to the tongue, batteries, second propane tank, etc., when loading the under seat compartments. The tongue weight should be 10% of the coach weight.

As tempting as it is to put bike racks on the back of the trailer this is not generally considered a good idea, the extra weight that far back can drastically affect the towing stability of the trailer. Carry your bikes inside the trailer or in the tow vehicle if possible.

Weight is weight, whether it is in the trailer or tow vehicle, the more stuff you pack the heavier your "rig", increasing the stopping distance required in an emergency.


(Taken from Boler Manual)

Trailer towing tips: towing a trailer with care and safety requires a certain amount of experience before setting out on the open road. Always remember that the handling and braking characteristics of your car may be changed considerably by the added weight of the trailer. Until you learn the "feel" and how to cope with these changes, it is important to drive with extra caution.

Before Starting: it is a good idea to practice turning, stopping, backing in an area away from heavy traffic. This practice will help you gain experience in handling the extra weight and length of the trailer. Also check lights, tires and mirror adjustments.

Starting: carefully check mirrors to observe traffic flow. It is a good idea to check the brakes of the car and trailer before turning into traffic.

Turning: remember that the trailer wheels will be closer than the car wheels to the inside on curves. Avoid soft shoulders, curbs etc., by driving slightly beyond your normal turning point. Signal all turns. Avoid sudden maneuvers.

Passing: allow extra distance for passing another vehicle. After passing be sure you have ample clearance for trailer before returning to the driving lane. Always signal well in advance of each move.

Following and stopping: remember trailer weight may increase the distance required to stop. For each 10 mph allow at least one length of your car and trailer between you and the car ahead. You will need this "cushion" of space foe emergencies and to permit safe stops, and allow for unfavorable road conditions.

Backing: skillful backing with a trailer requires practice. Try this easy method to help control direction. Keep your right hand at the bottom of steering wheel. To move trailer left, move your hand left. To back to right, move hand to the right.

Down grades: on long or steep down grades reduce speed and use a lower transmission range to assist braking, as outlined in your car Owner's Manual.

Long-up-hill grades: when ascending long up-hill grades the possibility of engine over-heating can be reduced by shifting transmission to a lower range of gear.

To change a flat tire: place your jack at the rear trailer bumper and remove the wheel as you would on your car.


There is a hole for a lock in the lever mechanism on the hitch coupler, a lock should be used when towing to insure the lever does not come unlatched, and when the trailer is parked to help prevent it from being stolen.

Wrap the safety snugly chains around the hitch and lock the ends together, Bolers with the lever mechanism locked have been hauled away by looping the chains over the hitch ball on the tow vehicle.

As an extra precaution there are boots that lock on one of the wheels available at most RV suppliers.


Your Boler most likely came from the factory with 13" wheels, if you are going into the back country and wish to have more clearance under the trailer axle it is possible to switch to larger wheels. Make sure you have at least 3" clearance above the wheels when the trailer is fully loaded, it may be necessary to add spacers to raise the coach as well. The offset of the replacement wheel hub must be identical to the factory wheels to allow the necessary side clearance for the tires.

The bolt pattern on a 5 bolt hub is measured from the center of a stud to the circumference of an imaginary circle running through the center of the studs at a spot directly opposite it.

Most Bolers have a 4 1/2" - 13" rim with low offset, apparently similar rims were used on 1970's vintage Maverics and Pintos, 14" rims were used on Ranger and Mazda trucks.

New Wheels

13" wheel is 4.5" wide and has a 2.62" pilot diameter.  It has a .50" inset (also known as a positive .50" offset). That means the center line of the rim is 1/2" inward of the plane of the fixing face.

Available from Vintage Trailer Supply


The hub is attached to a rubber mounted arm on the axle. The arm is attached to a square shaft inside a square tube supportred by four rubber cylinders.

Models manufactured in Western Canada had a Torflex brand manufactured by Dexter.

More info available from DexterAxle.com

How To's & Info

Acorn Nuts On Pop Rivets

Boler Specs.

Cushion Templates

Door Sag Quick Fixes

Drawer Above Fridge

Making a New Frame

Replace a Window Crank

Scissor Jack Levellers

Screen Door

Small Mods & Discoveries

Wiring and Batteries

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