P0744 Ford Ranger – What Intermittent Lock-Up Really Means and How to Fix It in Brisbane.

P0744 Ford Ranger comes uninvited…You’re driving your Ford Ranger—maybe it’s loaded with gear, maybe it’s towing a trailer, or maybe you’re just cruising on the highway. Everything feels mostly fine. But occasionally, it doesn’t. There’s a slight surge at cruise, a hesitation when coasting down, or a moment where the revs don’t seem to match the speed. It’s subtle, but something’s off.

Later, when a scan tool is plugged in, you see it. P0744 Ford Ranger Torque Converter Clutch Circuit Intermittent. Most people don’t know what that means. And unfortunately, many mechanical workshops don’t explain it clearly either. But if you’re seeing P0744, your torque converter is no longer locking up the way it should—and it’s not something you should ignore.

At Brisbane Tuning & Turbo, we’ve seen this fault in a growing number of 6R80-equipped Rangers. It’s one of the early signs that the lock-up clutch inside your torque converter is failing to hold pressure consistently. If not addressed, it can lead to heat build-up, converter degradation, and ultimately complete driveline failure. That’s why we’ve built a diagnostic-first approach—Redorq TQ+—to detect and correct this fault before things escalate.

Let’s walk through exactly what this code means, what causes it, and how to fix it properly.

What Does P0744  Actually Mean in a Ford Ranger?

P0744 Ford Ranger is triggered when the transmission control module (TCM) detects that the torque converter clutch (TCC) is not behaving as expected. More specifically, it sees a mismatch between the commanded lock-up state and the actual lock-up response.

This doesn’t mean the clutch has failed completely. In fact, it’s working—just not reliably. Occasionally, the clutch locks when it should. Sometimes it doesn’t. Sometimes it locks, then slips under load. That inconsistency is what sets off the code.

If your Ranger is showing this code, it means that TCC pressure control is erratic. The system might engage the converter clutch too aggressively, not at all, or fail to hold pressure once applied. And when it happens intermittently, it becomes hard to detect without proper scan logging.

This is why P0744 is dangerous.

It’s not a hard failure. It’s an intermittent fault that behaves like tuning lag, injector surge, or road vibration—until it doesn’t.

How It Feels Behind the Wheel

Drivers often report the following symptoms:

You might notice the vehicle “surging” slightly at light throttle, particularly around 70–100 km/h. The revs fluctuate by a few hundred RPM even though your foot is steady. Sometimes it feels like the truck is “hunting” for a gear. Other times, you’ll notice a soft jolt or drag when slowing to a stop, as if something is still holding. Fuel economy might take a hit. Cruise may feel rougher. You might lose that clean lock-up feeling that these transmissions usually deliver when towing or driving unloaded.

In most cases, there’s no limp mode. The check engine light may or may not appear. But the code will be there—often stored quietly, waiting to be triggered again under the right driving load.

It’s subtle enough to ignore. But over time, it causes damage.

Why It Happens in the 6R80 Transmission

The 6R80 is a strong transmission. But it’s also used in applications where lock-up clutch engagement is frequent and aggressive, especially in Australia. That includes towing, off-road torque loads, tradie work, and even long-haul commutes.

Here’s why it fails:

The torque converter contains a clutch that locks the engine and transmission together under cruise. This improves fuel economy and reduces heat. But it relies on precise modulation from a pressure control solenoid and clean hydraulic behaviour through the valve body.

When the friction surface of the lock-up clutch begins to wear, or when the solenoid can no longer modulate pressure correctly, you get slip. Not complete disengagement—just enough slip for the transmission to detect that lock-up isn’t consistent. That’s when P0744 logs.

At Brisbane Tuning & Turbo, we see this most often in Rangers that:

Rangers Tow regularly.

Have never had their transmission fluid serviced.

They are used in heavy stop-start traffic with a load.

Have previously logged P0741 or P2757. Click on these links to understand the connections between the faults.

Have mild ECU remaps without TCC calibration

What’s Causing the Fault

There are usually three culprits behind P0744:

Why General Workshops Miss It?

If a shop plugs in a basic scan tool and sees no active warning light, they might just clear the code.

If the fluid hasn’t gone black or the trans isn’t slipping harshly, many assume the converter is fine.

Others may recommend a flush, or in the worst-case scenario, replace the entire gearbox without testing the converter at all.

The issue is that P0744 sits in a diagnostic grey zone. It’s not yet catastrophic, but it’s the moment just before things start to go really bad and very expensive. And if the fluid is borderline and the converter is still functional, there’s still time to fix it before you burn through the whole unit.

What We Do Differently: Redorq TQ+ Diagnostic Testing

At Brisbane Tuning & Turbo, we don’t just clear codes and guess. Our “Redorq TQ+ diagnosis” process uses a structured system that combines scan data, fluid analysis, and lock-up testing.

Here’s what we look at:

Converter slip vs commanded lock-up (graphed in real-time).

Solenoid modulation current and duty cycle.

RPM drop on lock-up events during cruise.

Lock-up hold time before disengagement.

Transmission fluid condition and colour.

Shift behaviour during throttle transitions.

This tells us whether the fault is electronic, hydraulic, or mechanical—and more importantly, if it’s repairable before failure spreads further.

Diagnosis costs $285 and takes around 60–90 minutes. You leave with a printed report, fault summary, and fix recommendation. No guesswork.

Repair Options: When to Rebuild and When to Upgrade

Once P0744 Ford Ranger is confirmed, there are two possible directions:

Redorq TQ+ Torque Converter Upgrade

Our Redorq TQ+ upgrade includes:

 A remanufactured converter with improved lock-up clutch friction.

Full transmission fluid flush and filter.

Optional heavy-duty transmission cooler.

Optional ECU tune to recalibrate TCC engagement.

Road test and verification of lock-up pressure and timing.

Most Ford Ranger customers pay between $2,900 and $3,900, depending on parts selected and necessity and budget.

We don’t replace the automatic transmission unless testing proves it’s needed.

What Happens If You Ignore It

P0744 Ford Ranger leads to further deterioration. The converter clutch slips more. Heat builds in the transmission. Fluid breaks down. Codes like P0741 and P2757 follow. Eventually, the converter locks up when it shouldn’t—or fails to lock when it should. Shudder, hesitation, and limp mode begin.

At that point, the repair cost doubles. You go from converter upgrade to full gearbox replacement, and your tow vehicle is off the road when you need it most.

Don’t Wait Until It’s Terminal – Book Your Automatic Transmission Diagnostic & Scan.

If you’ve seen P0744 on a scan tool—or if your Ranger is surging at cruise, dragging when coasting, or just feels off—it’s time to confirm the problem properly.

Book your Redorq TQ+ diagnostic for $285. We’ll test lock-up modulation, inspect your converter, and confirm whether you can fix it now or face a rebuild later.

Let’s catch it early—and keep your Ranger working, towing, and shifting the way it should.