The Problem

The Toyota Gd6 automatic vehicles have the following gear shift behavior that frustrates the owners.

1. Sensitive Gearbox

The automatic gearbox is extremely sensitive. When the owner tries to overtake or accelerate even slightly, the auto gearbox gears down 2 gears, revving unnecessarily high. When this happens, the engine revs go close to 4000rpm, and the Gd6 engine does not have peak power at that high revs. Peak power for these engines is between 2000 and 3000 rpm. So basically, the engine just makes more noise, but you struggle to accelerate.

2. Gear Shift Issues

When you drive at about 120 – 130km/h, the vehicle will not easily go into 6th gear, which is its top gear. You need to either drive faster or leave the accelerator to get it into 6th gear. But when you get a slight uphill or press the accelerator a bit, it will go back to 5th gear again. And then the process of getting it into 6th starts all over again. Because it does not want to go into 6th gear, it makes the engine run at a higher rpm, making it less fuel efficient.

The Answer

The question on everyone’s mind is why does the gearbox react this way. The answer is simple. The computer that controls the gearbox is programmed to react this way. The gearbox does what the computer tells it to do.

The Solution

Now that we have determined that the problem is the way the gearbox computer is calibrated. It is safe to say that the solution to this problem is to put a better program into the gearbox computer. That is exactly what we at AVB Tuning were able to do. With our gearbox computer program, your auto transmission gearbox will react similar to when you drive a manual bakkie. It does not gear down for no reason. It keeps the engine speed between 2000 and 3000 rpm to maximize the use of the power curve.

Addressing the Problems

Before: The automatic gearbox is extremely sensitive.

After: The automatic gearbox allows you to accelerate without kicking down 2 gears. When you accelerate very aggressively, it will still only gear down one gear. This ensures the engine works in its peak power range.

Before: When you drive at about 120 – 130km/h the vehicle will not easily go into 6th gear, which is its top gear.

After: The automatic gearbox will go into 6th gear even if you drive only 100km/h. It will also allow you to accelerate and not kick down to 4th gear. When you accelerate mildly, it will stay in 6th gear. When you accelerate aggressively, it will go only one gear down and keep the engine speed in the optimal power range.

Beware of “Gearbox Calibration”

Many tuning companies advertise Engine tuning with gearbox calibration. We are not sure what exactly they mean by gearbox calibration. What we know is all our customers who first went for the “gearbox calibration” said they did not feel an improvement in the gearbox behavior.

We offer a 100% money back guarantee if you are not completely satisfied with the gearbox reaction. The Gearbox control will be reset back to the original settings in this case. But rest assured we have not yet had even 1 money back request.