Not sure I understand the context of the question/relevance to Alvis. Anyway, home grown WWI subsidy trucks used steel wheels - I'd need to double check if that was actually part of the specification - whereas most imported trucks did not or were inconsistent.
An intriguing early trailer for sale. Probably not military but interesting nevertheless. Why don't they show a picture of the name/data plate!?
Postage: Royal Mail 1st class @ £3.70 - lol
https://www.ebay.co.uk/itm/143649422263?ul_noapp=true
It's either a F60L or a C60L - 'F' and 'C' for Ford and Chevrolet respectively, '60' for 60cwt (3 ton) and 'L' for long chassis.
The C15A was a Chevrolet 15 cwt, with 'A' for four wheel drive (as opposed to C15 for the two wheel drive version).
Of course it would help if I could type! I should have said Alvis-Straussler Ltd.
Some info here: https://someinterestingfacts.net/straussler-armored-car-ac1-ac2-and-ac3/
Interesting, with the 'H' serial number and the front brackets for the winching spades, presumably another converted artillery tractor?
(There's one on Milweb at the moment:https://milweb.net/webvert/a3886/95991 )
There are several pictures of these K2/Y loudspeaker vans (possibly all the same vehicle!). Other vehicles were used, such as White scout cars.
Pictures below from IWM official collection.
It's clearer expanding the online images, rather than these low res images - it's Royal Navy Voluntary Transport.
The car in the last three is a Vauxhall, of course.
Some IWM pictures. The caption for the first two say they are drivers from the Women's Naval Car Service - but I can't read the shoulder flash!
A 21081
A 21082
A 23634
A 23634
A 23636