HGV's in Neutral ?

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Sun 26 Sep 2010 09:44
HGV's in Neutral ? - veryoldbear

Near us here on the A34 on the Oxfordshire / Berkshire borders is a long and rather steep hill. HGV's normally crawl up, but coming the other way, I'm darn sure they come down at well over 60 mph. Do they run down in neutral to avoid the speed limiter? Mmmmm.

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Sun 26 Sep 2010 12:32
HGV's in Neutral ? - a900ss

If it's long steep hill, they will not be in neautral. Best to leave it in gear as you will get some engine braking or even be able to use the exhaust brake to help slow the vehicle and stop it running away at high speed.

What is probably happening is just the weight of the vehicle on the incline is speeding the vehicle up. Speed limiters on HGV's don't apply the brakes, they merely cut the power when you hit the limiter. This means on a long hill, the engine is still in gear, no power is being offered by the engine as it's over it's s[eed limit (actually, the engine running will help control the speed) but the lorry's weight pulls it over the limit.

Hope that makes sense.

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Sun 26 Sep 2010 16:26
HGV's in Neutral ? - gordonbennet

Think you'll find that HGV's going over 60 downhill will be pre 56 plate, or foreign or Irish.

56 plate and newer will have digital recorders fitted and these register overspeeds on a drivers digi card, reputable companies take a dim view of 'overspeed' being recorded on their trucks, reputable companies also have their tachograph charts analysed professionally and will discipline drivers for overspeeds on older vehicles.

Apart from that a modern trucks computer would log free wheeling and it would likely be picked up at service time, and they are usually so high geared now that to be overrevving the engine would likely mean 90+mph, so no point, dangerous and likely to get the sack sharpish.

Out of cog used to be a regular way of travelling down hill at one time when an artics normal maximum governed speed might be 40 to 50 mph, affectionately known as 'Irish Overdrive'...so i'm told.

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Sun 26 Sep 2010 23:06
HGV's in Neutral ? - craneboy

Must confess to doing this many times years ago, when taking six wheel rigids on night runs across the M62 between Bradford and Cheetham Hill in Manchester. A lovely illuminated stretch of motorway with not a speed camera in site. I would knock the engine out of gear and travel down for what seemed an age just dabbing the brakes. A bit naughty, but it didnt half give my numb right foot a lovely rest.

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Tue 28 Sep 2010 00:02
HGV's in Neutral ? - wemyss

Funny but I asked only the other day my son in law who is a Texaco tanker driver why HGVs brake lights regularly come on when they are running down the slight hill heading west down the dual carriageway to markeaton island at Derby.

His answer was exactly as described by Gordon with the added information that their vehicles have angle indicators somewhere on the trailer which log the amount of leaning over going through roundabouts and is an automatic call in to the boss for a caution when exceeding a certain amount.

wemyss

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