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Idaho Doubles and Triples Test

You'll haul double trailers through Idaho's mountain passes, so this test helps you handle those grades safely.

Questions

80%

To Pass

Minutes

93 questions · 25 min time limit · 80% to pass

Opens in a practice window — choose your mode inside.

Reviewed by Jack Mahana, CDL Instructor (13+ years)

Last verified: August 2026

All questions sourced from the official Idaho CDL handbook and FMCSA regulations.

About the Idaho Doubles and Triples Test

Idaho's roads demand a lot from drivers pulling doubles and triples. You'll navigate steep grades on US-95 and White Bird Hill, or battle crosswinds on I-84 near the Snake River. This practice test focuses on the skills you need to keep those trailers stable and safe.

Idaho's economy relies on trucks hauling potatoes, timber, and goods. Doubles are common on interstates like I-15 and I-84, especially between distribution centers. But winter weather adds risk – black ice near Lookout Pass or sudden snow squalls in the Panhandle mean you must master braking and coupling.

We've pulled questions straight from the Idaho CDL handbook. You'll see air brake checks, coupling procedures, and weight distribution rules that apply to local operations. Each question includes an explanation so you learn why the answer matters for Idaho driving.

Take this test multiple times until you score 80% or higher. Then schedule your DMV appointment and bring your knowledge. Idaho doesn't let you skip the T endorsement – you must earn it.

Topics Covered

✓Coupling and uncoupling procedures – critical for Idaho's steep grades where a poor coupling can lead to disaster.

✓Air brake systems – you'll need them on long downhill runs on I-84.

✓Speed limits and braking distances – Idaho's open highways require careful stopping.

✓Weight distribution – hauling potatoes or lumber requires proper load balance.

✓Multi-unit vehicle inspections – Idaho DOT checks are thorough.

✓Emergency procedures – blowouts in remote areas like central Idaho demand quick action.

Study Tips

Study the Idaho CDL handbook's doubles and triples section. Focus on coupling steps – most test questions come from that. Practice inspecting dummy couplings and gladhands if you can. Idaho DMV skill tests emphasize a full pre-trip.

Use our practice test to identify weak spots. Retake it until you consistently get 17 or more correct. Many Idaho drivers fail because they skip air brake questions. Don't make that mistake.

Book your knowledge test appointment online. Bring your permit, proof of residency, and $50 fee. The T endorsement costs an extra $10. You can do it at any Idaho DMV office that offers CDL testing.

Idaho Specific Information

Idaho DMV offers CDL knowledge tests at most offices – Boise, Coeur d'Alene, Idaho Falls, Twin Falls, and more. You need an appointment for skills tests. Walk-ins are rare, so call ahead.

Fees: $50 for CDL knowledge test (includes all endorsements). The doubles/triples endorsement adds $10. Skills test is $90. Bring a valid truck for the road test – it must pass a pre-trip inspection.

You can take the knowledge test in English or Spanish. Idaho doesn't offer a written test in other languages. If you fail, you must wait one day to retest. No limit on attempts per year, but each test costs the same fee.

Frequently Asked Questions

Do I need a separate endorsement for doubles and triples in Idaho?

Yes, you need a T endorsement on your CDL to pull multiple trailers. It's a separate knowledge test from your general CDL.

Can I use my own truck for the Idaho CDL road test?

Yes, but it must pass a pre-trip inspection. The truck needs to be properly equipped with functioning lights, brakes, and coupling devices.

Where in Idaho can I take the doubles and triples skills test?

Most major DMV offices offer it. You'll need to schedule an appointment. Check with your local office for availability – some smaller offices don't have the space.

What's the minimum age to get a CDL with doubles/triples in Idaho?

You must be at least 21 to haul doubles or triples across state lines. Idaho allows intrastate hauling at 18, but many jobs require interstate travel.

How many questions are on the Idaho doubles/triples knowledge test?

20 questions. You need 16 correct to pass. That's 80%. Our practice test mirrors that exact format.

Reviewed by Jack Mahana, CDL Instructor (13+ years)

Last verified: August 2026 · FMCSA-compliant content