How to Drain a Nissan Patrol Fuel Tank: TB48 & TB45 Complete Guide

Yes, you can drain a Nissan Patrol fuel tank. Whether you should DIY it depends on what's in there and which engine you have. Here's the full picture.

Patrols hold a lot of fuel. Up to 140 litres in the long-range tanks. That's not a job you want to do in your driveway with a jerry can.

Why people drain a Patrol's tank

Most of the time, it's something gone wrong. Not routine maintenance.

The big ones we see across Perth:

• Wrong fuel. Petrol in a diesel Patrol (TD42, ZD30), or diesel in a petrol Patrol (TB48, Y62). Both are bad. The first is worse.
• Water in the fuel. Common after a flooded servo, dodgy jerry can, or a tank that's sat half full for months.
• Old fuel after long storage. Patrols often sit between trips up north. Fuel that's been in there a year goes off.
• A bad batch from the servo. It happens. Ben's seen it twice this year in Perth alone. The fuel looks fine but the engine won't run right.
• Before a fuel system rebuild. Fuel pump replacement, injector work, or tank repair all need the tank empty first.

If any of that sounds like your situation, our fuel drainage service covers it.

Nissan Patrol engines and which fuel goes in which

This is where people get caught out. "It's a Patrol, must be diesel, right?" Not always.

Patrols have run a lot of different engines over the years. Here's the short version:

Petrol Patrols

• TB42 (4.2L straight-six, GQ era)
• TB45 (4.5L straight-six, GU early)
• TB48 (4.8L straight-six, GU later)
• Y62 V8 (5.6L V8, current Patrol)

Diesel Patrols

• RD28 (2.8L six, GQ)
• TD42 (4.2L six, GQ and GU)
• ZD30 (3.0L turbo, GU)

The most common mistake we see? Someone fills a TB48 with diesel because they assume any big 4WD takes diesel. The TB48 is petrol. Big, thirsty, petrol. If you've just done this, don't start the engine. Call now.

Going the other way is more common still. Diesel Patrol owners pulling up to a green nozzle on autopilot. If that's you, here's what to do with petrol in a diesel.

TB48 fuel economy reality

Let's address the TB48 question head-on, because it's the one bringing most people to this page.

The TB48 is thirsty. There's no getting around it. Typical real-world fuel economy sits around 18 to 25 L/100km combined, based on owner reports across forums and reviews. Towing or on the sand, you'll see closer to 28 to 35 L/100km.

That's just the engine. 4.8 litres, naturally aspirated, big iron block, no modern fuel injection trickery. It does what it does.

What can make it worse?

• Dirty injectors. Years of carbon means each squirt isn't as clean.
• A blocked fuel filter. The engine works harder for less.
• Water or contamination in the tank. The engine runs lean or misfires, you push the throttle further to compensate.
• A failing fuel pump. Pressure drops, combustion suffers.

If your TB48 used to drink 20 L/100km and now sits at 28, the fuel system is worth a look. A full drain and flush won't turn it into a Prius. But it'll get it back to its honest baseline.

What's involved in draining a Patrol fuel tank

Here's the high-level. Not a how-to guide. Just so you know what you're paying for when a professional does it.

Step 1: Make the area safe. Fire extinguisher within reach. No phones, no ignition sources, no static-prone clothing. Patrols carry a lot of fuel and a lot of vapour.

Step 2: Find the access point. Most Patrols don't have a useful drain plug. You're going in through the fuel pump access hatch (under the rear seat on some models) or via a low-point fuel line from underneath.

Step 3: Pump it out. Explosion-proof pump, grounded jerry cans rated for fuel, slow and steady. 140 litres takes time even with proper gear.

Step 4: Drop the tank if needed. Heavy contamination, water, or wrong fuel means the tank often needs to come out for a proper clean. That's a workshop job on its own.

Step 5: Flush the lines. Pulling the fuel out of the tank doesn't clean the fuel rail, injectors, or filter. That's a separate flush step.

Step 6: Replace the fuel filter. Always. New filter every drainage. No exceptions.

Step 7: Refill and bleed. Especially on the diesels (TD42, ZD30). Bleeding air out of the lines is what gets the engine running cleanly again.

If you're more familiar with utes, our Mitsubishi Triton drainage guide walks through a similar process on a smaller tank.

Why DIY tank draining on a Patrol is a bad idea

Look, we're not going to pretend you can't physically do this. People do. We've turned up to clean up the aftermath of a few.

Here's why it's a bad idea on a Patrol specifically.

Volume. 140 litres of fuel is a lot. That's seven 20L jerry cans, all full, all next to your driveway. One slip with a fitting and you've got a fire risk and a serious clean-up.

Static spark. Petrol vapour ignites from a tiny spark. Carpet, polyester jumper, your dog jumping out of the ute. A grounded transfer system isn't optional, it's the whole point.

Ground contamination. Spilled fuel in WA isn't just a mess. The Department of Water and Environmental Regulation can fine you for fuel reaching soil or stormwater. Cleaning contaminated soil is in the thousands.

You can't fully flush the system. Even if you get the tank empty, the fuel pump, lines, rail, and injectors all hold contaminated fuel. Without specialist gear you can't push that out cleanly.

The tank's awkward. On most Patrols the tank sits between the chassis rails. Access from underneath needs the vehicle properly lifted and supported. A trolley jack and some pavers isn't safe.

For contaminated fuel situations specifically, every minute the engine runs makes the damage worse. That's when you call, not when you start watching YouTube tutorials.

What we do when we come to a Patrol on the side of the road

Real flow, no marketing version.

You call. Tell us where you are, which Patrol, and what you put in. We dispatch from the nearest tech.

We arrive with the gear. Explosion-proof pump, rated fuel storage, replacement filter, fresh fuel of the right type. Everything to do the job on-site.

We make the area safe. Cones if you're on a busy road. Bystanders moved back. Engine off, key out, no smoking signs up.

We drain the tank. Through the pump access or via a fuel line. We don't usually drop the tank roadside unless we have to.

We flush the fuel system. Lines, rail, filter housing. Old contaminated fuel out, fresh fuel in.

We replace the filter. Standard part of every job.

We refill and bleed. TB48s start easy. The diesels need bleeding before they'll run.

We test it. Start, idle, brief drive test. If it runs clean, you're sorted.

For a Patrol, expect 60 to 90 minutes start to finish. Longer than a passenger car. The tank volume is the main reason.

If you put diesel in a petrol Patrol instead, the diesel in petrol flow is similar but the urgency is slightly lower. Still call. Don't start it.

Frequently Asked Questions

How much fuel does a Nissan Patrol tank hold?

Most stock Patrols hold 95L to 140L. GU and Y62 models with the long-range setup go up to 140L total across main and sub-tanks. Aftermarket long-range tanks can push that higher again. Always check your specific year and trim before assuming.

What's the fuel economy of a TB48 Patrol?

Real-world TB48 fuel economy sits around 18 to 25 L/100km combined, per owner reports and reviews. Highway alone can dip closer to 15 L/100km. Towing or off-road pushes it to 28 to 35 L/100km. It's not a frugal engine. Never was, never will be.

Can I drain a Patrol fuel tank at home?

You can. You shouldn't. 140L of fuel is a fire and contamination risk most home setups can't handle safely. Spilled fuel in WA carries real EPA penalties. A proper drainage needs explosion-proof equipment, rated containers, and a way to flush the rest of the fuel system.

Does a Nissan Patrol have a fuel drain plug?

Most Patrols don't have a useful drain plug on the tank. Drainage happens via the fuel pump access hatch (under the rear seat on many models) or a low-point fuel line accessed from underneath. Older diesel Patrols sometimes have a sediment drain, but it's slow and doesn't fully empty the tank.

How much does a Patrol fuel drain cost?

Mobile fuel rescue for a 4WD like a Patrol starts higher than the standard passenger car range. The exact number depends on tank volume, how much contaminated fuel, location, and whether the tank needs to come off. Call 0416 692 022 for a quote based on your situation before we head out.

Can you drain a Patrol with a full tank?

Yes. Full tank, half tank, quarter tank, doesn't matter. We carry enough rated storage to take all 140 litres if needed. A full tank just takes a bit longer to pump out. Same job, same process.

Will draining the tank fix poor fuel economy?

Sometimes. If your Patrol's economy got noticeably worse over weeks, the cause is usually contamination, a dying fuel filter, or a failing injector. A drain, flush, and filter change handles two of those. If the injectors are the problem, you'll need a workshop. Won't fix a TB48 being a TB48, though.

Patrol broken down? Don't start the engine

Patrol broken down with the wrong fuel or contamination? We come to you across Perth metro. No towing, no stress, no engine damage.

Call now on 0416 692 022. Available 24/7 across Perth and WA.

Ben's a qualified mechanic with 10+ years on Patrols and other diesels. You'll get straight advice from someone who knows the engines.

Not sure if it's wrong fuel or contamination? Have a look at our home page for the full service list, or get in touch and we'll work it out on the phone.