How To Tell If Torque Converter Is Locking Up

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What can cause a torque converter to lock up? How do you tell if your car’s torque converter is locking up? There are lots of questions you may want to ask regarding your car’s transmission system, which is the system that houses the torque converter.

Well, there are quite a lot of things that could cause a torque converter to lock up or damage entirely. This article will discuss how to tell if the torque converter is locking up and the possible precautions/actions you can take to keep things under control before it results in fatal transmission or engine damage.

What Can Cause a Torque Converter to Lock Up?

It is a bit confusing to tell the possible causes of converter lock up. However, cold engine temperature can cause this to happen.

There are also cases where the converter may lockup due to a “locked-up” overdrive unit. To better understand this, you need to know about Lockup Converters.

Read Also: Can ABS Sensor Cause Transmission Problem?

What is a Lockup Converter?

Simply put, a lockup converter is a type of torque converter that contains a clutch. The clutch automatically engages at some point during acceleration to “lockup” the engine to the transmission input shaft to deliver a direct 1:1 drive ratio.

Lockup converters are alleged to promote fuel economy and they are mostly what you’d find in the modern cars of today.

Actually, the lock-up clutch is designed to take the stress off the fluid coupling of the converter to decrease heat generation at higher cruising speeds.

How To Tell If Torque Converter Is Locking Up

What Can Cause a Torque Converter to Lock Up

When a torque converter locks up, it feels as if your car moved to a higher gear, even though you’re on the last gear already. Not all drivers do notice this transition because it happens very fast and swiftly.

For example, if you own a 4-gear automatic, when your convert locks up, it feels like your transmission moved to a 5th gear or extra overdrive.

That said, if you notice a further shift while driving with the last gear, it could be that your torque converter just locked up. However, torque converter lock-up isn’t a very serious issue.

It seems like a “direct drive manual clutch system” that takes off the stress from the fluid coupling and push is a full mechanical load.

Read Also: Symptoms Of A Bad Toque Converter

What To Do When Torque Converter Locks Up?

Most times, converters lock up and unlock without any reasonable action from the driver. That is to say, converters do lock up and unlock automatically.

Torque converters can unlock due to acceleration, deceleration, or slow speeds. You’d likely experience convert lock up and unlock, a lot, during a trip.

>>Learn what causes a torque converter to fail.


Knowing if the torque converter is locking up is all about “shifts.” You’d feel a shift in that could be it. However, torque converter lock-up engages through a solenoid installed in transmissions.

The solenoid gets energized and redirects fluid flow back, through the input shaft – this now increases pressure within the clutch area and causes it to engage with the torque converter’s front.

The whole action sees you cruising a solid 1:1 direct drive from the engine to the transmission.

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