Unlike our resident A66 Chipboard Champion Expert on the overnight Lockerbie Express I don’t claim to be a Driving God and like picking up new tips and tricks along the way, either through experimentation with various techniques myself or from people that have been doing the job all their life. I’ve done a lot of different stuff but relatively limited on liquid tanks; enough to get it safely from A to B without any drama or rolling it into a ditch (not sure about straight and level roads yet, this may be a challenge too far ) but those have been compartmental and/or with baffles. Baffleless is not hard, but requires more caution and extreme smoothness in one’s driving to prevent the yoyo-ing pendulum effect of the milk racing up and down the tank.
I remember being told years ago (by a tanker driver) that the trick was to time the gear changes just as the liquid goes from the ebb to the flow after it hits the rear of the tank, the theory being that while you’re mid gear change the flow is helping propel you a little. In reality I’ve found this makes absolutely no difference whatsoever (on a manual box) . What I’ve personally found to be key is to not get to the situation where the liquid is moving at all . I’ve found it’s not the timing of the gear changes, nor the speed or them, just simply that you do it all as smoothly as possible so that you can’t even feel you’ve done it. This is easy enough to do driving down a slip ramp, building up speed to join a motorway (for example), but easier said than done when you’ve started from a standstill and are pulling up a fairly steep hill where you need max throttle. A very slight easing of the gas, grease the clutch out smoothly, silky smooth change, quickly grease clutch back in, and progressively back on the gas without any harsh inputs seems to be the key to keep it all calm in the back and momentum going, at least with a manual box anyway.
So I have the manual boxes down to a tee now. The problem is the trucks with auto boxes . As good as auto boxes are, they don’t work well with liquid (Scania auto 3 pedal opticruise), especially not when you’re 3/4 full. The gear changes are too snappy (no smoothness, just on/off) and impossible to predict with any degree of accuracy so you can’t prepare to come off the gas a little for the change to keep the liquid calm, you end up with it racing up and down the tank, driving like a nodding donkey . I’ve tried less gas, but that just confuses the box as it thinks you’re not on a hill so changes up, doesn’t have the torque to pull you up in that gear, so changes back down, each time creating a riot in the back. I’ve got that ■■■■■■ off with it that I flick the box into M when pulling away and do the changes myself then once up to speed, flick it back to auto for sorting itself out at junctions, roundabouts, hill descents etc. Another pet hate with them is they can’t ‘see’ the terrain ahead and I do a lot of hills and valleys with many small crests and dips in between. In a manual you’d just leave it in the same gear as you’d know you’d have enough torque in that gear to get you over the brow of the crest ahead even with the revs dying to nearly nothing, so the milk would stay calm, but the auto sees the revs dropping rapidly and “helpfully” drops a gear for you, only to change back up again a few seconds later as you start gaining a little speed into the next dip - each time creating havoc in the back. I suppose like all technology it has its limitations but just feels to me that this work would be easier/simpler with a manual box.
Any tips from the seasoned artic milk tanker drivers here, or is this just how it is with the auto boxes and you rock your way down the roads and just put up with it? I refuse to be defeated!