With a model range that’s been around for more than 10 years, and a regular best-seller in that time, the Ford Ranger 4X4 has become one of this country’s most visible work and play 4X4 pickups. Tough, dependable, and highly tuneable, the Ranger has carved out a niche in the aftermarket scene with massive support and a host of in-depth tuning knowledge to call on.

While there are several different models, the two big differences in the range can be split between the 2006 – 2011 PJ/PK Ranger and the 2012+ PX Series. The DNA of both is very different with the PJ/PK featuring Mazda-based powertrain technology, and the PX onwards using Ford’s Duratorq engine family (shared with Mazda's BT-50). For the purposes of this piece, we will split the two model lines into separate platforms (as indeed they are).

We enlisted the help of Matt Jackson from Horsepower Factory (HPF) in Victoria – who specialises in putting together performance packages for all Ranger models – to compile this article; all based on real-world tuning and modification results.

WORDS BY MARTIN DONNON, IMAGES BY ARNOLD ARCHIVE

The Ford Ranger has been one of the country’s best-selling 4X4 pickups for almost 10 years. It’s highly tuneable and reliable, here’s everything you need to know about tuning the Ford Ranger.

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Flash tuning, performance chips and estimated power gains
The good news is all versions of the Ranger can indeed be flash-tuned, and all of them deliver outstanding results when carried out correctly. As per most other 4X4s, the cost can vary between tuners but expect to pay around $1150 - $1600 for a professional dyno tune. And check the fine print on your contract because most flash tuners will keep your vehicle’s tune on record and restore it if the system’s been reset, only charging you for labour. The only ‘odd man out’ in the Ranger family is the current bi-turbo 2.0L four-cylinder diesel found in the PX3 (some), Raptor (and Everest). The software encoding to enable flash-tune access is still being worked out, but don’t expect it to take more than a few months from the time of writing.

The PJ/PK 3.0L T/D responds well to tuning but the results, according to Matt at Horsepower Factory, can vary. A typical flash-tuning gain is around 30%-50% on these engines with most of the gains coming from tuning the air-fuel ratio correctly (no richer than 18:1 at full load). The factory air-fuel ratios can vary wildly, so dialling these in correctly on the dyno is a must when it comes to the PJ/PK. Boost is only increased 2-3psi to get a safe and reliable result.

With this inherent variance in mind, Matt doesn’t recommend fitting a ‘chip’ unless it is tuned to match the vehicle on the dyno. Any guesswork in fuelling these engines can result in melted pistons and other associated engine dramas.

The later-generation PX Ranger 3.2L Duratorq engine also responds well to tuning. Indeed, the five-cylinder Ford engine makes a lot of torque down low when programmed correctly and will give excellent gains of up to 35% before the factory turbocharger runs out of airflow at around 2900rpm. This is evident in both torque and boost falling away the further the engine is revved.

Boost setting needs to be monitored carefully when using the factory turbocharger, as running more than 2-3psi additional boost pressure (particularly in PX2 onwards) can result in failed turbocharger assemblies (read: bent fins, under-bonnet ‘howl’, and a lack of performance). 

The Piezo-style injector used in the 3.2L also demands only a high-quality programmable Chip can be used that directly drives the fuel injector rather than just upping the pressure. Increased pressure results in noisy/rattly injectors and invariably leads to premature (and expensive) injector failure.

Have a look at the dyno graphs HPF has supplied to get a feel for the shape of the power and torque curves for each model when the tuning process has been carried out correctly.

Bottom line is there are indeed good gains to be had, and if you select the right tuner, you’ll get great results with very little downside.

BELOW The PJ Ranger ran a Mazda engine and a flash-tune offers a performance gain of around 30%.

ABOVE This graph shows the result of an ECU remap only on a 2008 PK Ford Ranger.

ABOVE The graph shows the gains after a turbocharger upgrade on a Ford Ranger PX1.

ABOVE This graph shows the performance improvement on a Ranger PX2 3.2L after a flash tune which increases fuel and turbo boost; throttle response is tweaked to improve pick-up and smooth out flat spots.

“The good news is all versions of the Ranger can indeed be flash-tuned, and all of them deliver outstanding results.”

What’s the gain from a bigger exhaust?
While there are no big jumps in power or torque by fitting an aftermarket exhaust on any of the Ranger models there is the normal positive effect of reducing EGT that less restriction behind the turbine creates. Add to this the off-beat five-cylinder burble of the PX series cars which (and don’t laugh here) gives them a similar sound to a Lamborghini V10, and there are some good aural arguments for upgrading your exhaust system.

Notably, in 2016, the Ranger was factory fitted with a DPF system (diesel particulate filter), which reduces the tuneable engine note you can get by adding an aftermarket exhaust system due to the DPF interrupting the sound waves coming from the engine. The good news here is that, save for normal wear over time there are no inherent issues with the Ranger PX2/3 DPF system. Matt told Unsealed 4X4 he’s tested Rangers with and without DPF in place and states there is no measureable difference in either power or torque to be had by changing out or illegally deleting DPF units.

Keep your cool
There are a host of intercooler upgrades available for the PJ/PK Rangers which can vary in price. You should expect to pay around $1100 for something decent that will keep inlet temperatures under control during real-world driving. The big catch here is that you won’t see much, if any, gain on the dyno with an aftermarket intercooler as they only shine in continual high-load real-world applications (think: towing). Even if you’re not modifying your Ranger for ‘performance’, if you’re going to be towing anything bigger than a 6x4 trailer then there are massive benefits to installing a properly engineered aftermarket intercooler.

See, as inlet temperatures in the PX get hotter – such as when towing or working hard off-road in low-range – the factory-installed engine computer will send a torque reduction signal to the engine causing a power drop that you can feel through the seat of your pants. And you don’t want this when you’re towing. A quality aftermarket intercooler should be able to keep inlet temperatures as close to ambient as possible and in all driving situations.

ABOVE An aftermarket intercooler next to the original unit from a Ranger PX.

ABOVE If you do nothing else, consider fitting an aftermarket intercooler if you’re going to be towing with your Ranger.

What about a turbocharger upgrade?
According to those who know, the factory turbocharger on the PJ/PK is well matched to the character of the engine, having enough flow left in reserve to make solid power and torque gains across the entire rev range via a tune. The factory turbocharger itself, according to Matt, doesn’t lend itself to the fitment of a larger compressor or turbine wheels due to space constraints in the physical turbocharger assembly. This means any upgrade requires a complete turbocharger change (and possibly manifold as well) which is something that can become expensive on older Rangers and for no real reason when you’re only searching for reliable performance gains.

The PX Ranger is a different story altogether. The PX1 uses a cast compressor wheel in its Garrett GT22 turbocharger, and HPF gets right into this with its TorqMax Ranger Turbo Program. Just like many other aftermarket tuning houses out there HPF replaces the cast compressor wheel with a larger billet hi-flow unit and machine the housing to suit. The aim of the game with Ranger is to increase compressor flow to match the engine and stop the power curve tailing off at 3000rpm.

Later PX2 and PX3 derivative Rangers use a smaller GT20 turbocharger, but with a factory billet compressor wheel which can match the output of the stock PX1 unit and do so with better low-end response. The catch here is that the GT20 has a smaller shaft and bearing arrangement which can make it prone to failure when asked to perform at more than stock boost levels. That said, the upgraded billet wheel GT22 turbochargers can bolt directly into place, and work on all models as a straight replacement with no tuning required.

Tuned properly with 23-24psi of boost pressure there are some good gains right across the rev range from fitting an upgraded compressor-equipped PX turbocharger. The feeling of having one of these in place is best described as the engine not ‘falling off a cliff’ as the tacho sweeps and continuing to pull another 500 – 700rpm higher in the rev range.

What about a fuel system upgrade?
Custom ECU Flash Tuning gives the ability to control larger injectors on the Ranger and take advantage of the higher boost and airflow that an aftermarket turbocharger can provide. The most common upgrade here is a 30% larger straight fit injector which can significantly raise the fuel system capability and generate numbers up to 180kW (at the rear wheels) which is starting to get pretty serious indeed.

That said, altering fuel pressure in Ranger (particularly the PX with its Piezo-style injector) is never a good thing and can result in severe engine knocking and ultimately injector failure. Always use a larger injector and tune to suit rather than bump the rail pressure. It will end in tears every time.

Is there anything you need to look out for?
Matt tells us he’s heard of turbochargers wearing out over time, losing balance and bending blades, which will not only reduce the turbochargers efficiency, but also cause it to make a racket. The best fix here is a new, or rebuilt turbocharger but beware of cheap, too-good-to-be-true turbochargers of the Internet, they can be a Pandora's box of problems.

PX Rangers aren’t immune from their own little list of problems, but none of them are an epidemic as such. Split cold-side intercooler hoses and split plastic intercooler tanks are both quite common and, as such, there are a host of aftermarket parts on offer to (silicon pipe kits and intercooler kits) that can fix this.

EGR temperature sensors are also a common ‘check-engine light’ warning on the PX Ranger with plenty of them giving trouble over time. The replacement is a simple $90 factory part though, so, once more, no big deal.

Last but not least, is the GT20 turbocharger on the PX2-onwards failing. This is easily detected (read: heard) thanks to a howling noise from under the bonnet under light acceleration. So, if you hear the beginnings of this ‘police-siren’ style noise you’ll know your turbo is on the way out. Just the excuse you need for an upgrade along with some tuning.

What else do I need to know?
Just like other late-model diesel there are a host of supporting parts that can be put on the entire Ranger series that make a good thing better. Matt tells us very few Rangers escape HPF without fitment of, at least a catch can, and with lots of upside and no downside this is a good idea (you can read/watch our fitment of a diesel catch can via this link).

The factory Ranger’s airbox while adequate for stock vehicles shows some inlet restriction on those with an upgraded billet compressor wheel in the GT22. HPF are undergoing a development program at the moment for an OEM quality airbox that removes the inlet restriction and will gain a reasonable handful of extra killer-watts and Newton’s finest.

Tuning ain’t tuning…
Properly tuning a late-model common-rail diesel is not just a case of cranking up the fuel pressure and adding boost. Like many other modern ECUs, the PX Ranger ECU has numerous different torque maps that it uses to calculate how much fuel to add to make the desired engine torque, like 'pedal-desired-torque map' and 'torque-limiter map' and 'torque-to-fuel map' and even a 'smoke-limiter map'.

Each one of these maps will independently limit the power, and this is done to stop the engine from smoking, to give the transmission the correct torque signal so it can apply the correct pressure based on actual engine torque, and more besides. Many 'Tuners' out there, via ECU remapping or fancy plug-in Chips, only alter the final 'fuel-injection table' and this will not pass on the true engine torque to the transmission, meaning it can be detrimental to transmission longevity, traction control and other functions Ford felt necessary to implement.