Changing between forward drive modes in an automatic

[YorkshireJumbo]

Auto boxes are generally more sensitive to acceleration than deceleration, so under acceleration you can more easily control them with your right foot. Under deceleration, you may have to make manual choices more often. That said, modern more sophisticated auto boxes may have better sensitivity to your requirements when decelerating or braking.

Not quite sure of the triggers as it's only happened once or twice, but mine will drop from 5th to 3rd if I lift off quickly and apply the brakes hard when going downhill. It's only happened in extremis, so I still need to flip it to manual on long descents.

If your box is reluctant to change up, have the fluid level checked and / or consider a fluid change.

Thanks - it's the manual override that has started to ignore a push on the gear-lever to change up. Had the ATF changed at the last service, and the level isn't too hard to check. Fully auto works as expected, as does the downchange function. Pity it doesn't "blip" the throttle, but it adds an element of interest trying to make the change down as seamless as possible...

[Mr Cholmondeley-Warner]

Thanks - it's the manual override that has started to ignore a push on the gear-lever to change up. Had the ATF changed at the last service, and the level isn't too hard to check. Fully auto works as expected, as does the downchange function. Pity it doesn't "blip" the throttle, but it adds an element of interest trying to make the change down as seamless as possible...

Sorry, that was a bit of a simplistic suggestion, glad you're on top of it. I particularly reacted to the "when cold" part of your initial remark. Is the selector connected by a cable or electric? If cable, it may be cable adjustment. If electric, possibly a defective microswitch?

They're all different, so I'll stop trying to play amateur mechanic at this point

[YorkshireJumbo]

Thanks for your thoughts, anyway. It's Honda's normal "gearlever on the dashboard" setup with the usual PRND-D3, but you can move the lever from D sideways to M, where you then have a sequential-type '+' and '-' to change manually. I was assuming that the auto side is cable and the manual side is microswitched, but now you've got me thinking....

It's not crucial, as I tend to use the manual for downshifts or holding a gear, and then flip it back to auto once the need has passed. I can wait for the next service unless it gets worse

[jcochrane]

Thanks for your thoughts, anyway. It's Honda's normal "gearlever on the dashboard" setup with the usual PRND-D3, but you can move the lever from D sideways to M, where you then have a sequential-type '+' and '-' to change manually. I was assuming that the auto side is cable and the manual side is microswitched, but now you've got me thinking....

It's not crucial, as I tend to use the manual for downshifts or holding a gear, and then flip it back to auto once the need has passed. I can wait for the next service unless it gets worse

If I understand your gearbox correctly I would probably only use D for towns and full manual at all others.

[YorkshireJumbo]

If I understand your gearbox correctly I would probably only use D for towns and full manual at all others.

It seems that the manual mode is meant to be "sportier", because it tends to "lock-up" much less readily. This means that 60mph is 2000rpm in 'D' and 2500rpm in 'M'. I tend to leave it in 'D' and use 'M' occasionally on long journeys. I do tend to use 'M' when I need the engine braking on hills or smaller roads (or when pushing on, but the car's an MPV and the family don't appreciate that...)

[jcochrane]

If I understand your gearbox correctly I would probably only use D for towns and full manual at all others.

It seems that the manual mode is meant to be "sportier", because it tends to "lock-up" much less readily. This means that 60mph is 2000rpm in 'D' and 2500rpm in 'M'. I tend to leave it in 'D' and use 'M' occasionally on long journeys. I do tend to use 'M' when I need the engine braking on hills or smaller roads (or when pushing on, but the car's an MPV and the family don't appreciate that...)

My preference for driving autos in D or full auto for towns, primary A roads and motorways is that the car tends to select the gear that I would select if driving a manual car and is usually suitable for safety, control and balance. However once on typical minor A and B roads I find the inability of the auto box to look ahead and asses hazards (bends , crestings , junctions other road users etc) results in gear selection and timeing that I might not choose. My choices would be based on assessing the hazard and selecting and timing gears to maximise safety, balance and control rather than only on throttle openings, load etc.. For me an auto box just can't take into consideration all the factors to make the best descision. So that's why I prefer the manual approach for these roads. That's just my personal view and I'm sure others will have their own for reasons that are just as valid for them.

[kfae8959]

Jon, the following Blog article on automatics won't necessarily answer your specific questions, but you may find it useful.

http://www.bespoke-group.co.uk/wordpress/2011/04/advanced-defensive-performance-fleet-safe-driving-control-course/getting-the-best-out-of-an-automatic-gearbox/

At the risk of going wildly off-topic, could I ask Mark to say more about why he chooses to use the automatic Audi for his "advanced roadcraft" video, especially given the tone this article starts with?

David