Vauxhall Movano - Difficulty selecting first gear whilst moving

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Thu 15 Nov 2012 11:32
Vauxhall Movano - Difficulty selecting first gear whilst moving - Maceman

Am having issues with first gear selection. I'm getting a grinding noise when shifting from say 3rd or 4th into 1st gear whilst the vehicle is in motion. (For example whilst slowing down approaching a junction). Clutch pedal is fully depressed, but gears still grinding. Only happens if I shift whilst vehicle is travelling at or above say 10mph, below this speed there is no problem. Surely if the clutch pedal is fully depressed it shouldn't matter how fast the vehicle is travelling? Is this likely indication of clutch wear or something else, synchro maybe? Any thoughts appreciated. (vehicle is 2005 2.5cdti approx 120k miles on original clutch)

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Thu 15 Nov 2012 11:36
Vauxhall Movano - Difficulty selecting first gear whilst moving - unthrottled

Only happens if I shift whilst vehicle is travelling at or above say 10mph, below this speed there is no problem

That's asking a lot from your 1st gear synchro. You need to double clutch and rev match if you want to get back into first at anything above a crawl.

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Thu 15 Nov 2012 13:11
Vauxhall Movano - Difficulty selecting first gear whilst moving - Collos25

What do they teach people when they learn to drive 4th to 1st when on the move and wonders why it objects,the mind boggles.

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Thu 15 Nov 2012 16:38
Vauxhall Movano - Difficulty selecting first gear whilst moving - galileo

What do they teach people when they learn to drive 4th to 1st when on the move and wonders why it objects,the mind boggles.

The OP clearly is guilty of cruelty to dumb machinery, through ignorance of how it works. He will duly suffer appropriate financial punishment when the gearbox fails.

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Fri 16 Nov 2012 14:51
Vauxhall Movano - Difficulty selecting first gear whilst moving - Maceman

The OP clearly is guilty of cruelty to dumb machinery, through ignorance of how it works. He will duly suffer appropriate financial punishment when the gearbox fails.

Thanks for your insightful assesment, it's true, unfortunately I was not born with a full working knowledge of vehicle mechanics. Maybe, just maybe, that would be the reason I posted in this forum, in the hope that someone with lesser ignorance might explain it to me. And someone has (without being condescending).

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Fri 16 Nov 2012 16:15
Vauxhall Movano - Difficulty selecting first gear whilst moving - galileo

The OP clearly is guilty of cruelty to dumb machinery, through ignorance of how it works. He will duly suffer appropriate financial punishment when the gearbox fails.

Thanks for your insightful assesment, it's true, unfortunately I was not born with a full working knowledge of vehicle mechanics. Maybe, just maybe, that would be the reason I posted in this forum, in the hope that someone with lesser ignorance might explain it to me. And someone has (without being condescending).

Maceman, my apologies if my comments caused you distress: the fact is that most people now take vehicles for granted - expect them to start when the key is turned, go, steer, stop with minimal effort on the driver's part; this is how they are advertised and sold, so the customer can't really be blamed, and drivers' handbooks are not all as helpful as they could be. This, perhaps, should be improved.

My first car (and the next half dozen) were 50s/60s (very second hand) models, I learnt how they worked by spending hours fixing them with blood, sweat and bad language.

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Thu 15 Nov 2012 13:37
Vauxhall Movano - Difficulty selecting first gear whilst moving - TeeCee

You put the clutch fully down. The input shaft and primary gear clusters are rotating at engine revs associated with the vehicle moving at that speed in 4th.

You then smack it into 1st, which is asking for significantly higher revolutions on the input side to match the same drive shaft at the other end and the synchro cones have to spin the front end of the thing up to that speed. With a shiny, new box and gentle pressure on the lever, that telltale long whirring sound with a rising note from the synchromesh system will be heard and it'll eventually drop into 1st. That sound is the synchromesh working its socks off (and wearing itself out) to match the gear cluster speeds.

The fact that the gears are crunching would suggest either that most of the synchromesh has already been worn away from this treatment, or that you are forcing the thing into 1st too rapidly and getting to the point where the gears mesh before the synchro has had time to cater for the godawful gear cluster speed mismatch you've just given it.

Edited by TeeCee on 15/11/2012 at 13:38

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Fri 16 Nov 2012 15:02
Vauxhall Movano - Difficulty selecting first gear whilst moving - Maceman

Thanks for your response TeeCee, I didn't understand how the synchros and gear selection worked, but now can make sense of it to some degree.

For the record, I think I may have not explained myself entirely clearly and I think I've also exaggerated the speed at which I was shifting....it was more likely around 5mph (although fully laden at 3500kg the van would struggle go much under 12mph in anything but first gear without stalling!).

When I am shifting down to first it is during braking to a stop, so the revs and roadspeed are dropping rapidly. So all I was doing was braking to a junction, realising I had to stop, braking more and selecting first as I slowed right down, not realeasing the clutch pedal until after I had stopped and was pulling away again.

I realise now that I was probably shifting prematurely and will adjust my driving style and only change to first once the vehicle is stopped or virtually stopped.

Edited by Maceman on 16/11/2012 at 15:05

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Fri 16 Nov 2012 16:39
Vauxhall Movano - Difficulty selecting first gear whilst moving - unthrottled

(although fully laden at 3500kg the van would struggle go much under 12mph in anything but first gear without stalling!)

This is a good point. There are a lot of drivers who believe that you should never shift back into first while the vehicle is moving. This is balls. Labouring the engine in second or slipping the clutch to save the synchro cone on first is silly.

The mechanically sympathetic way to do this is to depress the clutch and roll out of gear. Let the clutch out, then blip the throttle to bring the revs to slightly above where they would be if the vehicle was in first gear. Then depress the clutch and select the gear. It sounds like a faff, but a smooth 2-1 downshift is a joy to behold. No embarrassing nose-diving.

When rolling up to a junction, it is often easier to roll out of whatever gear you are in prematurely and start the rev match from neutral. This avoids having to spasm your left leg in a double clutch depression. Don't worry about being exact with rev matching-anything is better than nothing!

Edited by unthrottled on 16/11/2012 at 16:41

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Fri 16 Nov 2012 23:49
Vauxhall Movano - Difficulty selecting first gear whilst moving - mickeybo

The clutch pedal operation causes the injection pump to momentarily reduce it's output when the clutch is disengaged to permit smoother gear changing. The 1st & 2nd gear sycronising hub the most used on any vehicle needs replacing Regards Mickeybo

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If you cover no more than 100 miles per day and have easy access to a charging point at home or work, then an EV is ideal for you.

Is an electric car right for me?