Thread: Chipping the gear box

With my 32in tyres, I find the gear box reluctant to kick down. It seems to hang on to top gear way too long. Can you chip it, reset it or adjust a cable so it will kick down sooner at highway speeds.

In a recent long road test it hung onto top on a long hill until about 1200 rpm (Engine was struggling) trans let the speed drop to about 70, then it kicked down and revs jumped up to about 3000 in 2nd! It seemed to realize it had gone past a speed ok for 3rd and dropped right back to 2nd. I kept the pedal in the exact same spot that had it sitting at 2000 at 100k an hour. It's very economical at this rpm with these tyres, sips 14-15l/100k with a roofrack.

I'm about to fit a truespeed correction unit, wondering if this will actually help since it will tell the engine my wheel speed is faster than it thinks! I have a feeling it might make it worse!

Originally Posted by mrapocalypse

Due t the lack of any respnses, I did my own homework and the sluggish change is for some reason related to the LPG system.

Lpg on, slow to kick Down.

Soon as you turn it off.

Bingo, away he goes.

D2 V8's just LOVE petrol.....

You must have a peculiar gas conversion, it shouldn't make a zac's worth of difference! I wonder if the gas system is drawing power from somewhere wrong, like a fuel pump circuit. It could be causing limp home mode or something, if the ECU "determines" the pump is struggling, keeps the revs down? Does manual gear selection of 3rd gear make the engine run happily?