How much slower is an HGV than a car?

[V8mate]

I'm creating some analytical tables for a haulage firm. They run 44t 6x4 trucks with three axle trailers at maximum weight.

Google Maps suggests typical journey times for routes, but these are, obviously, for cars. By what factor is a truck typically slower?
1.5x car journey time? 2x?

[V8mate]

Thanks for the replies so far. I'm certainly ensuring that any routes I'm putting into Google Maps are HGV-friendly; no nipping through villages or backroads etc.

And I'm dealing with the loading and tipping times separately.

Really interested to hear of as many experiences as possible

[V8mate]

Glenn63 said:

Mile a minute plus 50%, if that goes over 4 hours add another 45 mins for a break and you won’t be far off.

Thanks

[V8mate]

citizensm1th said:

Just for giggles generally motorway and a roads

That's really interesting!

Especially your average speed; I was guessing at 40-45mph for journeys longer than 10 miles, but 37mph makes quite a difference!

[V8mate]

V8mate said:

citizensm1th said:

Just for giggles generally motorway and a roads

That's really interesting!

Especially your average speed; I was guessing at 40-45mph for journeys longer than 10 miles, but 37mph makes quite a difference!

Over 10mpg though?! What's the unit?

[V8mate]

loggo said:

Remember A to B will not be the same as B to A.

Thankfully, they usually go from B to C, then on to D, before arriving back at A!

[V8mate]

Glenn63 said:

Mile a minute plus 50%, if that goes over 4 hours add another 45 mins for a break and you won’t be far off.

Trouble is, most of my routes are 15-40 miles, and that means that getting started and out onto a dual carriageway, and then the reverse at the other end, have a disproportionate impact on the overall time.

[V8mate]

48k said:

I've written some software for the transport department of a company who operate artic flatbeds and wagon and drags. The software has a configurable "lorry time multiplier" for estimating routes which takes data from Google maps. Currently its set to 1.4 (ie. whatever real time route calculation Google comes up with, the software adds 40% to the journey time). They haven't changed this value for a while so I assume its working out quite well for them as a rule of thumb.

Cheers. That's a useful perspective.
My initial 1.5 was definitely too generous; checking some 'real life' references today on their vehicle trackers some were barely a few minutes slower than Google on 20-30 mile routes, while others were certainly closer to the 1.4 you suggest.

Cheers