Michigan SOS mechanic test

Recreational Trailer

Recreational Trailer is one of the 20 Secretary of State mechanic certification tests. Here's what the test covers, according to the state's published outline.

Topic guide · questions soon

What's on the test

Official topic	Weight
Electrical diagnosis Trailer tail lamps Ground wire problems Turn signal circuits Determine voltage drop Trailer stop lamps Brake controllers 4-Wire connectors Current supply for trailer brakes Electrical symbols Flasher diagnosis Color codes Causes of blown fuses Current flow / resistance	36%
Brake diagnosis Loss of brakes Grabby brakes Dragging brakes Erratic braking, surging Pull to one side during braking Adjusting trailer brakes Brake shoe recognition	26%
Springs / hitches Leaf springs Equalizing hitches Adjustment of hitches Types of trailer springs Spring maintenance	16%
General knowledge Surge brakes Reducing sway Wheel bearing adjustment Hydraulic brake lines Metric measurements Tire wear diagnosis	12%
Wheels / hubs Wheel bearing diagnosis Wheel bolt torque pattern	10%

Source: SOS Mechanic Testing Categories Overview (PDF). Test format: most SOS mechanic tests have 55 questions, and a few have 65–100 (SOS FAQ). Passing scores vary by test; your result letter shows the passing score and your score.

Practice questions coming soon

The Recreational Trailer practice bank is being written to the official outline below. The All-Mechanic pass will include it when it launches.

Banks available now: Engine Repair · Front End, Suspension & Steering · Brakes & Braking Systems · Electrical Systems · Engine Tune-Up & Performance

Test-day facts

Taken on a touch-screen kiosk at any Secretary of State office. Schedule through SOS e-Services.
$18 per test (effective July 1, 2026).
“Quick pass”: the test ends once you reach the minimum passing score.
No reference materials or electronic devices are allowed.
If you don't pass, your result letter breaks down your performance by subcategory.

Source: michigan.gov/sos mechanic testing

Recreational Trailer test FAQ

How many questions are on the Michigan Recreational Trailer test?

The Secretary of State says most mechanic tests have 55 questions and a few have 65 to 100. The test is “quick pass,” so it ends as soon as you reach the minimum passing score.

What topics are on the Recreational Trailer test?

The SOS Mechanic Testing Categories Overview lists: Electrical diagnosis (36%), Brake diagnosis (26%), Springs / hitches (16%), General knowledge (12%), Wheels / hubs (10%).

How much does the test cost, and where do I take it?

Each mechanic test costs $18 (effective July 1, 2026). Tests are taken on a touch-screen kiosk at any Secretary of State office; pre-register and schedule through SOS Online Services. Approved automotive schools can also test their students.

Are these the real test questions?

No. MI Trade Prep questions are original practice items written to the official topic outline. They are not actual exam questions, and MI Trade Prep is not affiliated with the Michigan Department of State.

Sources: SOS mechanic testing · SOS mechanics page · SOS mechanic FAQ