Kei Truck Inspection Checklist: What to Check Before You Buy

Let Me Save You Some Money

I've bought six kei trucks over the years. Two were great. Two were fine after some work. Two were expensive lessons. My neighbor Gary's first Hijet? He didn't check the frame, and three months later he was looking at a repair bill that cost more than the truck. Ask me how I know the feeling — my first Minicab had a head gasket issue I would've caught in five minutes if I'd known what to look for.

This is the checklist I wish someone had handed me before I bought that '92 Minicab. Print it out, bring it with you, and don't let anyone rush you through it. A seller who won't give you time to inspect is a seller who's hiding something.

Grab a flashlight, a flat-head screwdriver, a magnet, and a rag. That's all you need.

1. Frame and Undercarriage — The Most Important Check

I'm putting this first because it's the one that matters most and the one most people skip. A bad engine is a weekend swap in my garage. A rotted frame means you own a parts truck.

Where to Look

Get under the truck. Yes, actually under it. Bring a creeper if you have one. Hit these spots with your flashlight:

• Rear crossmember — the horizontal bar behind the rear axle. This is rust's favorite target on every kei truck I've ever seen. On my '96 Hijet, I caught a pinhole here during a routine inspection. If I'd waited another winter it would've been structural.
• Frame rails behind the rear wheels — road spray collects here and just sits. Poke along the bottom edge of the rail.
• Cab mount points — where the cab bolts to the frame. Rust here means the cab is eventually going to shift. On mid-engine trucks like the Carry and Hijet, there are usually four mount points. Check them all.
• Battery tray area — acid drips cause localized rot that spreads. Pull the battery if the seller lets you and look at the metal underneath.
• Leaf spring mounts — front and rear. The frame ears that hold the spring pins take a beating.

The Screwdriver Test

This is the most important 30 seconds of the entire inspection. Take your flat-head screwdriver and poke the frame in every spot I listed above. Not a gentle tap — actually push. If the screwdriver goes through the metal, or if the metal flakes away like a cracker, that truck has structural rust. Walk away. No negotiation, no "I can weld that." Walk away.

Surface Rust vs Structural Rust

Every kei truck that's been driven has some surface rust. That's fine. Here's how to tell the difference:

• Surface rust: Orange discoloration on the surface. Metal underneath is still solid. Screwdriver bounces off. A wire wheel and some Rust-Oleum fixes this in an afternoon.
• Scale rust: The surface is flaky and pitted but the metal still has thickness. This is a warning sign — it's heading toward structural if not treated. Negotiate the price down and plan for rust treatment.
• Structural rust: Metal is paper-thin, perforated, or gone entirely. Screwdriver pokes through. Edges crumble when you touch them. This is a frame replacement or a parts truck.

Regional Risk

Not all Japanese rust is equal:

• Coastal trucks (Okinawa, anywhere near the Sea of Japan): Salt air corrosion. It's everywhere, even in spots that don't see road spray. Check the roof, door bottoms, and frame — all of it.
• Snow country trucks (Hokkaido, Tohoku, Niigata): Road salt and snow chain damage. Undercarriage gets hammered but the upper body might be fine.
• Rural/mountain trucks (inland prefectures): Often the cleanest. Less salt, less humidity. These are the ones you want.

If the auction sheet lists the prefecture, look it up. A truck from Nagano is a better bet than a truck from Niigata, all else being equal.

2. Engine

Cold Start — Non-Negotiable

Tell the seller you want to hear a cold start. If you show up and the engine is already warm, leave and come back another time, or walk. A warm engine hides rough idle, hard starting, smoke, and knocking. Every engine sounds decent when it's warm. Ask me how I know — I bought my first Minicab on a warm start and spent the next six months chasing cold-start misfires.

If the seller says "I just warmed it up for you" — that's not a favor. That's a concern.

What to Listen For

Stand next to the engine bay (remember, it's usually under the seat or behind the cab) and listen:

• Knocking on startup: Deep, rhythmic knock that fades after 30 seconds could be oil pressure building. If it doesn't fade, that's rod knock. Walk away.
• Ticking: Light ticking that goes away when warm is usually valve lash — adjustable and cheap. Persistent ticking at all temperatures could be a collapsed lifter or something worse.
• Excessive valve noise: These are small engines with mechanical valve adjustments. Some noise is normal. A sewing machine sound is fine. A jackhammer is not.

Fluids Tell the Story

Pop the oil cap and look:

• Golden or dark brown oil: Normal. Someone changes the oil.
• Black and gritty: Neglected, but not fatal. Plan on a flush and change.
• Milky, chocolate-milk color: Coolant in the oil. Head gasket failure. This is expensive and on a 660cc engine it's often not worth fixing. Walk away unless the price reflects a full engine rebuild.
• Oil level low: Either it burns oil or the owner doesn't check it. Neither is great.

Check the coolant too. Pop the radiator cap (only when cold):

• Green or blue and clear: Good. Someone maintains the cooling system.
• Rusty brown: The coolant hasn't been changed in years. The whole cooling system is probably corroded inside. Not a deal-breaker but budget for a full flush, new thermostat, and inspect the water pump.
• Oily film on coolant surface: Oil in the coolant. Head gasket. Same answer as milky oil.

Exhaust Smoke

Have someone rev the engine while you watch the tailpipe:

• White smoke on a cold morning that disappears: Condensation. Normal.
• Persistent white smoke: Coolant burning. Head gasket.
• Blue smoke: Burning oil. Worn rings or valve seals. The truck will run but it's drinking oil and it'll only get worse.
• Black smoke: Running rich. On carbureted trucks this could be a simple adjustment. On fuel-injected trucks it could be an O2 sensor or injector issue.

Rev It

Once it's warmed up, rev it through the range. Smoothly up to redline and back down. You're feeling for:

• Hesitation or flat spots in the power band
• Misfires (engine stumbling or popping)
• Any metallic rattling under load that wasn't there at idle

3. Transmission and Drivetrain

Manual Transmission

Most kei trucks are manual, and they're generally tough. But check:

• Shift through every gear at a standstill and while driving. Pay attention to 2nd and 3rd — these are the gears that grind first when synchros wear. If you feel any crunch or resistance going into gear, the synchros are going.
• Reverse: Should click in cleanly. Some grind is normal on reverse (many don't have a synchro for reverse), but it shouldn't be violent.
• Clutch engagement point: Should be in the middle of pedal travel, not at the very top. A clutch that grabs right at the top is nearly worn out.

Automatic Transmission

Less common but they exist:

• Check the ATF level and color. Should be pink or light red. Dark brown or burnt-smelling fluid means the transmission has been cooked.
• Drive it through all gears. Feel for harsh shifts, slipping (engine revs but the truck doesn't accelerate), or delayed engagement from a stop.

4WD — Test It

If the truck has 4WD (and you're probably buying one that does), test the system:

• Engage and disengage 4WD using the lever or switch. It should lock in with a firm click and come out cleanly. A sloppy transfer case lever that flops around means worn linkage at minimum, worn transfer case at worst.
• Drive in 4WD on dirt or gravel (never on dry pavement with part-time 4WD). Listen for binding, clunking, or grinding from the front axle.
• Full-lock turns in 4WD: At low speed, turn the wheels to full lock in both directions. Clicking from the front means worn CV joints. CV boots are cheap. CV joints on a kei truck require sourcing from Japan and are a pain to replace. Ask me how I know — Gary's Hijet went through two sets.

Differentials

While you're under the truck checking the frame, look at the differentials and transfer case for oil leaks. A weeping seal is maintainable. A steady drip means the seals are shot and the fluid level is probably low, which means the gears inside are wearing faster than they should.

4. Electrical

Kei truck electrical systems are simple, which is good. They're also 25+ years old, which means gremlins.

Lights — All of Them

Turn on everything and walk around:

• Headlights (low and high beam)
• Tail lights
• Brake lights (have someone press the pedal)
• Turn signals (front, rear, and side markers)
• Reverse lights
• Hazard flashers
• Interior lights
• Bed light (if equipped)

Burned-out bulbs are cheap. Lights that don't work even with a new bulb mean wiring issues, and chasing wiring issues on a 30-year-old Japanese truck with no English wiring diagram is not how you want to spend your weekends.

Gauges

Start the truck and confirm every gauge works:

• Temperature: Should climb to the middle after warming up. If it doesn't move, the sender is probably dead. If it pegs to hot immediately, the sender is grounded or you have an actual overheating problem.
• Fuel: Should match reality. Stuck on empty or full means a dead sender in the tank.
• Oil pressure (if equipped): Should show pressure at startup and settle at idle.

Climate

• Heater: These little cabs get cold. Turn the heat on and confirm it blows hot after the engine warms up. A heater that doesn't work could be a dead blower motor (cheap), a stuck blend door (annoying), or a clogged heater core (expensive for the labor, not the part).
• AC (if equipped): Many kei trucks don't have AC, and that's fine. But if it's supposed to have AC, confirm it blows cold. AC repair on a kei truck with R-12 refrigerant means a conversion to R-134a, and that's easily a $500-800 job if you can't do it yourself.

Extras

• Reverse melody/buzzer: Most kei trucks beep or play a little tune when you put them in reverse. If it doesn't work, it's either disconnected or the speaker is dead. Minor, but it tells you about maintenance attitude.
• Window regulators: Crank them up and down (or test the power windows if equipped). Manual regulators that are stiff usually just need grease. Power windows that don't work are an electrical rabbit hole.

5. Body and Cab

Doors

Open and close every door. Lift up on the door handle while it's open — if the door moves up noticeably, the hinge pins are worn. On a kei truck this means the door will eventually sag enough to not latch properly. Hinge pins are replaceable but it's a sign of high-use wear.

Bed Floor

The truck bed is a working surface and it shows.

• Stomp test: Stand in the bed and stomp in each corner and the center. Solid metal rings. Rusted metal crumbles or flexes. On my Hijet, the bed floor had been covered with a rubber mat that hid three rust-through spots. Always pull up the mat.
• Check the bed sides at the bottom edge where they meet the floor. Water sits in this joint and rots it from the inside out.

Windshield

Kei truck windshields are small and curved. A small chip becomes a full crack fast, especially in cold weather. Replacement windshields exist but they're not at your local auto parts store — they come from Japan and take 2-4 weeks. Look at the windshield carefully. Any chip bigger than a quarter is going to spread.

Seat Condition

Ripped or worn seats tell you the truck was used hard, which isn't necessarily bad — kei trucks are work trucks. But check under the seat for the engine access panel (on cab-over models). Make sure the seat frame isn't cracked and the mounting bolts are tight. Seat covers from Japan are around $50-80. Not a big deal.

Smoke Smell

A huge percentage of Japanese imports smell like cigarettes. The Japanese market has high smoking rates and these trucks were daily drivers. If the smell bothers you, factor in a full interior detail — ozone treatment, headliner cleaning, the works. Budget $200-300 or a weekend with baking soda and patience.

6. Tires and Brakes

Tire Age

Tread depth matters less than tire age on a truck that might have sat for years. Find the DOT date code on the sidewall — it's a four-digit number. First two digits are the week, last two are the year. So "2418" means week 24 of 2018.

Any tire over 6 years old needs to be replaced regardless of tread depth. Rubber degrades. Old tires lose grip, especially in wet conditions. A set of four kei truck tires is $200-400 depending on size. Factor this into your offer price.

Also check the size. Kei trucks use oddball sizes — 145/80R12, 155/65R13, and so on. Make sure all four match and that the size is actually available in the US. Some JDM-only sizes are hard to source.

Brakes

• Pedal feel: Press the brake pedal. It should be firm and stop about halfway down. A spongy pedal means air in the lines or worn master cylinder. A pedal that goes to the floor means serious problems.
• Parking brake: Set it on a hill. The truck should hold. A parking brake that doesn't hold is common (cables seize and stretch) but it's a safety issue and some states require it for inspection.
• Test drive braking: At 25-30 mph, brake firmly. The truck should stop straight. Pulling to one side means a stuck caliper or uneven pad wear. Pulsation in the pedal means warped rotors.

7. Documentation

Papers matter. Missing paperwork is the single biggest headache in kei truck ownership, and it's the one thing you can't fix in a garage.

What You Need to See

• Export certificate from Japan: Proves the vehicle was legally exported. Without this, titling gets complicated fast.
• US customs entry paperwork (CBP Form 7501 or equivalent): Proves it was legally imported and cleared customs.
• Title or proof of titling process: If the truck is already titled in your state, great. If it's not titled yet, make sure the seller can provide the chain of paperwork you'll need. Every state is different — some want the export certificate, some want a bill of sale, some want an inspection. Know your state's requirements before you shop.
• Auction sheet (if available): Japanese auction sheets grade the vehicle from S (like new) to R (repaired/accident). A grade of 3.5 or higher is generally clean. Below 3 means significant issues were noted. If the seller has the auction sheet, read it carefully — it's more honest than any seller will be.
• Maintenance records: Rare to have, but Japanese owners sometimes kept meticulous records. A truck with a folder of receipts is a truck that was loved.

No Title, No Deal

I cannot stress this enough. If the seller doesn't have a clear title or a clear path to getting one, do not buy the truck. I don't care how clean it is, how cheap it is, or how good the deal seems. A kei truck without a title is a lawn ornament. Pennsylvania learned me that lesson — Gary bought a Hijet without proper customs paperwork and spent eight months and $1,200 getting it sorted with the DMV. The truck was $4,500. The paperwork drama was almost as much as the truck.

8. Test Drive

You've checked everything standing still. Now drive it.

What You're Feeling For

• Highway speed: Can it actually maintain 45-50 mph? These are 660cc engines. Some trucks — especially loaded or lifted ones — struggle to hold highway speed on inclines. That might be fine for your use case, but you need to know.
• Steering play: At 30+ mph, the steering should feel connected. More than about an inch of free play at the wheel is worn steering components — tie rod ends, steering box, or rack. These are fixable but they add up.
• Vibrations: Any vibration at a specific speed usually means a tire balance issue or a bent wheel. A vibration that gets worse with speed could be a driveshaft balance or U-joint. A vibration only under braking is warped rotors.
• 4WD engagement while moving: If the truck is part-time 4WD, engage it at low speed on a loose surface. It should click in within a few feet. If you have to wrestle the lever or it grinds going in, the transfer case or front axle engagement is worn.
• Listen: Windows down, radio off. Listen for anything — clunks over bumps (worn suspension bushings), whining in gear (transmission bearings), clicking in turns (CV joints). These little trucks are quiet enough that you can hear problems easily.

Red Flags — Walk Away

These are non-negotiable deal-breakers. If you find any of these, it doesn't matter how good the price is:

• Frame holes or structural rust — a rotted frame cannot be safely repaired on a vehicle this small
• Milky oil or oily coolant — head gasket failure on a 660cc engine is often terminal
• No title and no clear path to getting one — you're buying a parts truck, not a road vehicle
• Seller won't let you cold-start the engine — they're hiding something
• Rod knock — that deep rhythmic knocking means the bottom end is done
• Evidence of major unreported collision — misaligned panels, fresh paint on one section, bent frame rails
• Odometer rollback — if the km seem too low for the year and condition, trust your gut

Yellow Flags — Negotiate the Price Down

These are problems, but they're fixable problems. Use them as leverage:

• Surface rust on the frame — needs treatment but isn't structural yet. Budget $200-500 for rust treatment and undercoating.
• Old tires (6+ years) — you'll need to replace them immediately. Deduct $300-400 from your offer.
• Dead battery — could just be a dead battery ($80), or it could be a parasitic drain that's been killing batteries for years. Ask how long the current battery has been in.
• No AC or dead AC — if you need AC, budget $500-800 for a conversion/repair. If you don't need it, irrelevant.
• Worn clutch — a clutch replacement on a kei truck runs $300-600 depending on the model and who's doing the work. Negotiate accordingly.
• Minor oil seep — valve cover gaskets and oil pan gaskets weep on old engines. A gasket kit is $30 and an afternoon in the garage.
• Smoke smell — $200-300 for a proper detail and ozone treatment.
• Non-working AC — already mentioned but worth repeating: this is a $500+ fix and a fair negotiation point.

The Bottom Line

Taking 45 minutes to inspect a truck properly will save you thousands. I've been turning wrenches for 30 years — 15 at Mack and the rest in my garage in Scranton — and the worst truck problems I've seen were all things the buyer could have caught before they signed anything. You don't need to be a mechanic. You need a flashlight, a screwdriver, your ears, and the willingness to walk away.

If a deal feels too good to be true, it is. If the seller is rushing you, there's a reason. Take your time, follow this checklist, and you'll end up with a truck that runs for years instead of a project that drains your wallet.

Now go find yourself a good one.

Related Guides

• The Complete Guide to Buying a Kei Truck — the full buying process from start to finish
• Rust Prevention and Treatment Guide — how to protect your truck after you buy it
• Finding a Kei Truck Mechanic — how to find someone who knows these trucks