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BenScoobert · 10-31-2010, 03:04 PM

I have a 2003 GMC Yukon XL 5.3 vortec.

Here in Britain petrol is pricey, so I run my yukon on LPG at less than half the price. I get about 18MPG(UK Gallon) but we can always do better

However, there is a long hill on my drive to work which I can coast down.
I was wondering does anyone know if it does damage if you still have the engine running but put the auto gearbox in neutral.

I have done it a couple of times and instead of reading 3Litres/100Km, it reads 1Litre/100Km.
Someone told me you shouldn't coast automatics, so until I find out more info I'm back to leaving it in drive.

10-31-2010, 03:04 PM	#1 (permalink)
BenScoobert EcoModding Lurker Join Date: Oct 2010 Location: UK Posts: 12 Yukon XL - '03 GMC Yukon XL SLT Thanks: 6 Thanked 0 Times in 0 Posts	Automatic transmission - coasting damage? I have a 2003 GMC Yukon XL 5.3 vortec. Here in Britain petrol is pricey, so I run my yukon on LPG at less than half the price. I get about 18MPG(UK Gallon) but we can always do better However, there is a long hill on my drive to work which I can coast down. I was wondering does anyone know if it does damage if you still have the engine running but put the auto gearbox in neutral. I have done it a couple of times and instead of reading 3Litres/100Km, it reads 1Litre/100Km. Someone told me you shouldn't coast automatics, so until I find out more info I'm back to leaving it in drive.