ASE Certification Guide

Medium/Heavy Truck · Test T8 · Preventive Maintenance Inspection

ASE T8 practice test: preventive maintenance inspection

T8, Preventive Maintenance Inspection (PMI), is the inspection test of the series: 60 questions (50 scored) in 75 minutes. Its questions ask you to check, measure and record against a limit more than to repair. Frame and chassis, which covers brakes, drivetrain, steering, tires and suspension, is 22 of the 50 scored questions.

  • 50 scoredquestions that count
  • 75 mintesting time
  • 25questions on the recert test
  • 15practice questions here

What T8 covers

Checked Oct 23, 2026 against each source linked in the table. Content areas and scored questions from the spec table in the 2026 study guide, p. 43.
FactDetailSourceChecked
T8 questions60 questions (50 scored + 10 unscored), 75 minutesASE Medium/Heavy Truck Study Guide 2026 · ASE: T1–T8 tests page
Master statusT2–T8 make Master Medium-Heavy Truck Technician; T1 is not requiredeach certification must stay current to keep Master statusASE: T1–T8 tests page · ASE Medium/Heavy Truck Study Guide 2026
Official ASE practice testASE sells official practice tests for T2 (28 questions), T4, T6 and T8 (25 each), 60 days to finishASE shows no price on the pageASE: official practice tests
A · Engine Systems10 scored questions (20%)Study guide, p. 43—
B · Cab and Hood5 scored questions (10%)Study guide, p. 43—
C · Electrical/Electronics10 scored questions (20%)Study guide, p. 43—
D · Frame and Chassis22 scored questions (44%): brakes, drivetrain, steering, tires and wheels, suspension, frame and fifth wheelStudy guide, p. 43—
E · Road/Operational Test3 scored questions (6%)Study guide, p. 43—

T8 practice questions

0 of 15 answered · 0 correct
Question 1 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During the PMI starter check at 500 A, the drop is 0.3 V across the positive cable and 0.3 V across the ground cable. The manufacturer's limit is 0.5 V total for a 12-volt system. The circuit:

Explanation

Incorrect: The positive side counts as much as the ground side.

Incorrect: The limit is for the total, so passing each cable on its own does not pass the circuit.

Correct: The 0.5 V limit is for the whole cranking circuit, so 0.3 V + 0.3 V = 0.6 V fails, and both sides need cleaning or repair.

Incorrect: Both cables are equal at 0.3 V; it is the 0.6 V total that fails, not the ground cable alone.

Question 2 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, a crack is found in a heat-treated frame rail. Technician A says the crack must be corrected before the truck is released. Technician B says welding the crack and adding a fish plate is the OEM-preferred permanent repair. Who is right?

Explanation

Correct: A cracked frame rail is a structural defect that is fixed before release; Technician B is wrong because a heat-treated rail is replaced, not welded.

Incorrect: Welding ruins the heat treatment, so a weld with a fish plate is at most temporary; the permanent repair is a new rail, so Technician B is wrong.

Incorrect: Only Technician A is right; welding a heat-treated rail is not an approved permanent repair.

Incorrect: Technician A is right: the crack must be corrected before the truck goes back into service.

Question 3 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, a tilt hood is properly aligned but will not stay securely latched. Technician A says a faulty hood-ajar sensor could prevent the hood from latching. Technician B says worn hood hold-down latches or hooks could cause this. Who is right?

Explanation

Incorrect: A hood-ajar sensor only reports the hood's position; it does not hold the hood or keep it from latching, so Technician A is wrong.

Correct: A hood that is aligned but will not stay latched points to worn hold-down latches or hooks; the hood-ajar sensor only sends a signal.

Incorrect: Only Technician B is right; the hood-ajar sensor has no part in holding the hood down.

Incorrect: Technician B is right: worn hold-down latches or hooks keep the hood from latching securely.

Question 4 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, a battery hold-down is missing, and the batteries shift in the box when rocked by hand. The technician should:

Explanation

Incorrect: Tightening the cable clamps does not stop the batteries moving and stresses the terminal posts.

Correct: Batteries that move in the box can crack cases, short to the box and break plates, so the correct hold-down is installed and tightened.

Incorrect: Rags soak up acid and can catch fire; they are not a hold-down.

Incorrect: Battery cables are not designed to hold batteries in place; leaving them loose is a defect.

Question 5 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

With adaptive cruise control set at 60 mph, the truck closes on a slower vehicle ahead. During the road test, the system should:

Explanation

Incorrect: Adaptive cruise is meant to keep working by slowing the truck, not to shut off when it sees a vehicle.

Incorrect: A full stop with the service brakes is not normal behavior; it slows only as much as the gap requires.

Incorrect: Holding set speed into a slower vehicle is how plain cruise control behaves, not adaptive cruise.

Correct: Adaptive cruise uses radar to slow the truck, with engine torque reduction, the engine brake and if needed the service brakes, to keep the set following gap.

Question 6 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

Soon after an EGR cooler replacement, the road test shows coolant loss and white vapor at the stack, but there are no external leaks. The cause could be:

Explanation

Incorrect: A torn air filter lets dirt into the engine; it does not use up coolant.

Incorrect: SCR condensate does not explain a falling coolant level.

Correct: Coolant loss with white vapor at the stack and no external leak, right after the cooler was replaced, points to coolant passing into the exhaust gas inside the EGR cooler.

Incorrect: A stuck-closed EGR valve stops recirculation and sets a code, but it does not consume coolant.

Question 7 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PM, which of these fifth wheel findings requires repair before the tractor is returned to service?

Explanation

Incorrect: Light surface rust on the top plate edges is cosmetic.

Correct: A cracked mounting bracket can let the fifth wheel separate from the frame, so it is repaired before the tractor goes back into service.

Incorrect: Fresh grease on the top plate is normal lubrication.

Incorrect: A release handle latched in the locked position is how it should be.

Question 8 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During an annual inspection, a drag link ball-and-socket joint is checked with hand pressure for motion, other than rotation, at its attachment point. Under Appendix A to Part 396, the joint fails when this motion exceeds:

Explanation

Incorrect: 1/16 in is far below the Appendix A limit, so a joint with that much motion still passes.

Incorrect: 1/2 in is far past the limit; a joint fails long before that.

Correct: Appendix A fails a steering ball-and-socket joint that shows more than 1/4 in of non-rotational motion at its attachment point under hand pressure.

Incorrect: 1/8 in is also tighter than the federal limit.

Question 9 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

Under Appendix A to Part 396, a rear impact guard on a trailer built after 1998 fails if its bottom edge is more than how far above the ground?

Explanation

Correct: Appendix A and 49 CFR 393.86 limit the guard's bottom edge to 22 in (560 mm) above the ground on trailers built after January 26, 1998.

Incorrect: 18 in is lower than the federal limit.

Incorrect: 20 in is lower than the federal limit, so a guard at 21 in would still pass.

Incorrect: 24 in is above the 22 in limit, so a guard there would fail.

Question 10 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, several different ECUs have logged intermittent low-voltage codes with matching timestamps. Which of these could be the cause?

Explanation

Incorrect: A failed wheel speed sensor sets a code in the ABS module only, not low-voltage codes across several ECUs.

Incorrect: A faulty coolant sensor sets a code in the engine module only.

Incorrect: A restricted fuel filter affects engine power, not module supply voltage.

Correct: A loose main chassis ground affects every module that returns through it, so low-voltage codes show up together with matching times.

Question 11 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

When checking truck tire inflation during a PMI, pressures should be measured:

Explanation

Correct: Recommended pressures are cold values, so tires are checked before the truck is driven.

Incorrect: Bleeding pressure from a hot tire leaves it underinflated once it cools.

Incorrect: Hot tires read higher than cold, so a reading right after a road test is not compared with the cold spec.

Incorrect: Thumping a tire only finds a flat; it cannot measure inflation pressure.

Question 12 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

This question contains the word EXCEPT. Under Appendix A to Part 396, a suspension fails the inspection if any of these is found EXCEPT:

Explanation

Correct: Light surface rust on a U-bolt is not a defect; Appendix A lists broken, missing or deflated spring parts and cracked or loose torque, radius or tracking parts.

Incorrect: A broken leaf in the spring pack is a listed defect.

Incorrect: A deflated air suspension (system failure or leak) is listed as a defect in its own right.

Incorrect: Appendix A fails any torque, radius or tracking part that is cracked, loose, broken or missing, with no further condition.

Question 13 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During an under-hood PMI, which of these leaks requires the truck to be held out of service until it is repaired?

Explanation

Correct: Fuel dripping onto a hot exhaust manifold is a fire hazard, and Appendix A fails any visible fuel leak, so the truck stays out of service until it is repaired.

Incorrect: A damp film at the water pump weep hole is monitored and recorded, not an out-of-service item.

Incorrect: A film on the power steering reservoir with no drip is a service item, not an out-of-service defect.

Incorrect: Slight oil seepage with no drip is recorded and scheduled, not a reason to hold the truck.

Question 14 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, the engine oil level is above the FULL mark and the oil smells of diesel fuel, but it is not milky. This indicates:

Explanation

Incorrect: Coolant in the oil makes it milky, and this oil is not.

Correct: Oil above FULL that smells of diesel means fuel is getting into the crankcase, from a leaking injector, seal or line.

Incorrect: Overfilling would not make the oil smell of diesel.

Incorrect: A diesel smell and a rising oil level are not normal at any age.

Question 15 of 15 · T8 Preventive Maintenance Inspection · 50 itemsNot answered

During a PMI, a technician services the coolant filter. Technician A says the coolant filter shutoff valves should be closed before the filter is removed. Technician B says the coolant's SCA level should be tested before choosing a precharged or non-precharged filter. Who is right?

Explanation

Incorrect: Closing the shutoff valves is right, but Technician B is right too: the SCA test decides which filter goes on.

Incorrect: Testing SCA first is right, and so is Technician A's step of closing the shutoff valves before removing the filter.

Correct: The shutoff valves keep coolant in the engine while the filter is off, and the SCA test result decides whether a precharged filter is needed, since too much SCA causes deposits and gel.

Incorrect: Both are standard coolant filter practice: close the shutoff valves, and test SCA before choosing the filter.

Answer every question to see your score

Area by area

Engine systems

10 scored questions: identifying the fuel or power type and its safety procedure, reviewing past records and driver reports, reading active and inactive codes, checking for oil, coolant, fuel and diesel exhaust fluid leaks, belts, mounts, cooling system and fuel tanks, and aftertreatment parts for damage or tampering.

Cab & hood

5 scored questions: warning lights and gauges, horns, safety equipment, seat belts, wipers and glass, mirrors, steps and grab handles, pedals, permits and inspection papers, cab mounts and the tilt cab.

Electrical/electronics

10 scored questions: batteries and cables, starting and charging checks, lighting and reflectors, trailer connections, and identifying high-voltage systems on electrified trucks.

Frame & chassis

22 scored questions. This is where T4 and T5 material comes back as inspection: brake adjustment and lining, air system checks, driveline and U-joints, steering lash, tread depth, wheels and hubs, springs, the frame and the fifth wheel.

Road/operational test

The smallest area at 3 scored questions: steering, braking, shifting and gauge behavior on the road test.

The inspection rules behind T8

Many T8 limits come from the Federal Motor Carrier Safety Regulations:

  • Annual inspection (396.17): every component listed in Appendix A to Part 396 must pass an inspection at least once in the preceding 12 months, with proof on the vehicle.
  • Inspection report (396.21): kept 14 months where the vehicle is housed or maintained.
  • Driver vehicle inspection report (396.11): not required when no defect is found or reported; when one is, the carrier repairs it or certifies that repair is unnecessary before the vehicle runs again, and keeps the report 3 months.
  • Limits you inspect against: tread depth in 393.75, brake lining and pushrod stroke in 393.47, steering lash in 393.209.

The CVSA out-of-service criteria are a separate roadside standard; when a question names one, use that one. All six sections were read on eCFR on Oct 23, 2026.

Inspect, record, then repair

Read what the stem asks. An inspection question wants the check, the measurement or the record. A repair can be correct work and still be the wrong answer to an inspection question.

Other T-series tests

T8, quick answers

How many questions are on the ASE T8 test?

60 questions and 75 minutes, with 50 scored. The recert test is 25 questions, 30 minutes.

What is the ASE PMI test?

It is T8, Preventive Maintenance Inspection: 50 scored questions in 75 minutes. It counts toward Master truck.