Hydrovac Pre-Trip Inspection Checklist: 15 Points Before Every Job

I've lost count of how many emergency calls started with "it was fine yesterday." No, it wasn't fine yesterday — you just didn't catch the problem until it stranded you today.

A real pre-trip inspection takes about 10 minutes. That's it. Ten minutes to catch the problems that would otherwise cost you hours of downtime, expensive emergency repairs, and angry customers. I've been fixing hydrovac trucks for 25 years, and I promise you: the operators who do proper pre-trips are not the ones calling me for roadside emergencies.

Here's the checklist I use. Print it, laminate it, stick it in the cab.

The 15-Point Pre-Trip Checklist

1. Walk-Around Visual Inspection

Before you even start the engine, walk around the entire truck. You're looking for:

• Fresh fluid puddles under the truck (oil, hydraulic, coolant, water)
• Tire damage or low pressure (visual check)
• Loose or hanging components
• Damage from yesterday (did someone back into something?)
• Boom position and security
• Debris tank door closed and latched

This takes 60 seconds and catches obvious problems. I had a contractor in New Jersey who caught a cracked hydraulic line during a walk-around — saved him from a $3,000 pump replacement that would have happened if he'd run it dry.

2. Engine Oil Level

Check it cold, before starting. You know how to do this — dipstick, wipe, reinsert, read. Low oil isn't just an engine killer; on hydrovacs, the engine works hard driving the PTO. Low oil under load is a death sentence.

If you're adding oil frequently, that's telling you something. Track it.

3. Coolant Level

Check when cold (don't open a hot radiator). Look at the overflow reservoir or sight glass. Low coolant means either a leak or worse. Find out which before you're overheating on a job site.

While you're there, look at the coolant color. Should be whatever color the manufacturer spec'd (usually green, orange, or pink). Brown or rusty? Time for a cooling system service.

4. Hydraulic Fluid Level

Your sight glass is your friend. Fluid should be visible in the middle of the glass when the system is cold. Too low and you risk pump damage. Too high and you might have another fluid (water, coolant) contaminating your hydraulic system.

Check the color too. Good hydraulic fluid is clear amber. Dark, milky, or foamy fluid means problems.

5. Water Tank Level

Know how much water you're starting with. Running the water pump dry kills it faster than almost anything. If you're heading to a job without a water source, make sure you've got enough.

Also check for leaks at tank fittings and the fill cap.

6. DEF Level (If Equipped)

Modern diesel trucks need DEF. Running out doesn't just trigger warning lights — on many trucks, it eventually limits your speed or power. Check it and top off before it becomes a problem.

7. Fuel Level

Obvious, but worth saying: know how much fuel you have. Running a diesel dry introduces air into the fuel system, which means bleeding the system before it'll restart. That's time you don't have on a job site.

Also: never let a diesel sit with a near-empty tank overnight. Condensation forms in empty tank space, and water in diesel fuel causes problems.

8. Tire Pressure and Condition

Kick the tires isn't good enough. Carry a gauge and actually check pressure. Look for:

• Obvious damage (cuts, bulges, embedded objects)
• Uneven wear patterns (alignment or suspension issues)
• Low pressure (all tires, including inner duals)

An underinflated tire on a loaded hydrovac isn't just a fuel economy problem — it's a blowout waiting to happen.

9. Belt Inspection

With the engine OFF, look at your drive belts. Check for:

• Cracks or glazing
• Fraying edges
• Proper tension (should deflect about 1/2" with firm thumb pressure)
• Signs of contamination (oil on belts)

A belt failure shuts down whatever that belt drives — could be the water pump, alternator, power steering, or PTO. Catching a worn belt is cheap. Emergency belt service is not.

10. Brake Check

Before you leave the yard:

• Press the brake pedal — should be firm, not spongy
• Check parking brake holds
• Low air warning works (if air brakes)
• Listen for air leaks with brakes applied

After you start moving:

• Test brakes at low speed before hitting the road
• Listen for grinding, squealing, or pulling

Brake problems on a loaded hydrovac are not something you want to discover at highway speed.

11. PTO Engagement Test

Engage the PTO briefly:

• Does the dash indicator work?
• Can you hear/see the blower spinning?
• Any unusual noises?
• Disengages cleanly?

PTO problems are common. Better to find them in the yard than on the job.

12. Boom Function Check

Cycle the boom briefly:

• Rotation left and right
• Extension and retraction
• Any binding, jerking, or unusual sounds?

If the boom isn't rotating smoothly, address it before you're on site trying to dig.

13. Vacuum System Quick Check

You don't need a full test, but verify:

• Door seals look intact
• Relief valve moves freely (manually cycle it)
• No obvious vacuum leaks (hoses, connections)

Vacuum problems are the #1 issue I fix. A quick check prevents the "it won't build vacuum" panic later.

14. Lights and Signals

All of them:

• Headlights (high and low)
• Tail lights
• Brake lights
• Turn signals
• Hazards
• Backup lights
• Work lights
• Warning/strobe lights

This isn't just legal compliance — it's how other drivers know what you're doing. A burned-out brake light on a heavy truck is a rear-end collision waiting to happen.

15. Safety Equipment Check

Make sure you have and know the location of:

• Fire extinguisher (charged?)
• First aid kit
• Triangles/flares
• Required PPE
• Any company-specific safety equipment

The Stuff People Skip (And Regret)

In my experience, these items get skipped most often:

Hydraulic fluid level: "I'll check it later" turns into running the pump dry and burning it up.

Belt inspection: Nobody looks at belts until one breaks. Then you're stuck.

Relief valve cycle: Especially in cold weather, that valve freezes up. 30 seconds of prevention beats hours of troubleshooting.

Tire pressure: Kick-and-look doesn't catch slow leaks. Use a gauge.

When Something's Wrong

If your pre-trip reveals a problem:

Minor issues (low fluid, belt tension, etc.): Fix it now. Takes 5 minutes.

Moderate issues (unusual noise, small leak, soft brakes): Don't take the truck out until you've identified the cause. Might be quick, might need help.

Major issues (grinding from blower, brake warning lights, visible damage to critical systems): Stop. Get it fixed. No job is worth a breakdown or accident.

Build the Habit

Pre-trip inspections only work if you actually do them. Every day. Not "when I remember" or "when I have time."

Build it into your morning:

• Get to the truck 15 minutes before departure time
• Do the walk-around
• Start the engine, do your in-cab checks
• Brief function test
• Hit the road knowing your truck is ready

Operators who do consistent pre-trips have fewer breakdowns. That's not an opinion — I've seen it over and over in 25 years of fixing these trucks.

Documentation

Keep a simple log. Date, mileage/hours, check completed, any issues noted. You don't need a fancy system — a notebook in the cab works.

This documentation:

• Creates accountability
• Helps track trends (oil consumption, recurring issues)
• Provides evidence for warranty claims
• Shows due diligence if something goes wrong

Get Help When Needed

Pre-trip inspections catch problems. But if you catch something you can't fix yourself, get it handled before it becomes an emergency.

I provide maintenance and inspection services throughout Pennsylvania, New Jersey, New York, and the DC area. For fleet operators, I offer fleet maintenance programs that include scheduled inspections.

Call me at 272-296-9637 if you need help with something your pre-trip revealed. It's always better to address problems on your schedule than on an emergency basis.

For more on keeping your truck running, check out my complete hydrovac maintenance guide and specific guides on blower oil maintenance and common operator mistakes.