View instructions
Safely pulling double and triple trailers requires knowledge and skill. If you want to pull double or triple trailers, you must add the Doubles/Triples (T) endorsement to your Class A CDL. The Ohio doubles triples test consists of 20 questions. To pass, you must correctly answer at least 16 questions (80%). The OH CDL doubles triples test covers the following sections of the Ohio CDL Manual: Driving Safely, Air Brakes (if you plan to operate vehicles equipped with air brakes), Combination Vehicles, Doubles and Triples. Take this OH CDL practice test now to prepare for the actual test! Important: Triple trailers are not legal in Ohio.
1. As part of your vehicle inspection, you are checking that air flows to all trailers. After using the trailer handbrake to provide air to the service line, you go to the rear of the rig. When you open the emergency line shut-off valve at the rear of the last trailer, you should hear:
air escaping from the open valve.
the service line valve close.
a mechanical vibration.
2. To prevent rollover, you should:
drive in the left lane whenever possible.
drive slower around corners.
drive faster on ramps and off ramps.
3. Warnings on low bridges or underpasses:
are often posted, but sometimes they are not.
are always posted.
must be posted.
4. To test your parking brake, do the following:
Speed up to 5 mph, then set the parking brake.
Set the parking brake, and gently pull against it in a low gear.
Set the parking brake while going downhill.
5. The application pressure gauge:
protects the tank and the rest of the system from too much pressure.
tells you how much pressure is in the air tanks.
shows how much air pressure is being applied to the brakes.
6. When possible, you should park:
so you will have to back up when you leave.
so you will be able to pull forward when you leave.
on the shoulder.
7. When you discover a fire, if the trailer doors are hot you should not open them because:
the temperature of the trailer should not be changed in any way.
with air many fires do less damage.
opening the doors lets air in and may make the fire flare up.
8. The tire load for each tire is stated:
on the tread of the tire.
on the inside of the tire.
on the side of the tire.
9. Do NOT use the parking brakes:
when you park for less than two hours.
if the brakes are very hot.
when you leave your vehicle.
10. When the wheels of a trailer lock up:
ABS will increase stopping power.
the vehicle will gradually come to a complete stop.
the trailer will tend to swing around.
Page 1 of 2
Next page

OH CDL Doubles Test

Number of questions: 20
Correct answers to pass:16
Passing score:80%
Share This Online CDL Test
Rate this CDL Doubles Test
4.8 out of 5
based on 191 votes