Gearbox torque limiter removal

Every automatic and dual clutch gearbox has torque limits written into its control
module. They are there to protect the clutch packs, the mechatronic unit and the gearset
from more than they were designed to handle.

Tune an engine past those limits and the gearbox pulls the engine back. You feel it as
a flat spot, a soft shift or a car that will not deliver what the dyno says it should.

When raising the limit is right

Where the manufacturer used one gearbox across a range of outputs, the limit in a lower
powered car is often conservative rather than absolute. A DQ381 behind a 190 is not
working as hard as the same box behind a 300.

When it is not

A box already at its design limit will not take more because the software says it can.
Raising a limit does not add clutch material. We look at what the box is, what it is
behind, and what it is being asked to do before we touch it.

More on our stage tuning and what the gearbox will take

For the trade

This is one of the jobs available through our dealer file service. Send the
original read, tell us the vehicle and what you need, and the file comes back
checked. If a job carries mechanical conditions on the car, they are listed in the
coverage table below and they apply to your customer’s vehicle too.

More about becoming a JFA tuning dealer