JeffA,
don’t listen too them although the replies have made me laugh, if it is a LGV it will be just behind the Cab, or 2 tanks a main and reserve.
Also some LGV’s have an extra Tank basically a reserve for the Australian Market that will give you that extra comfort area clearly marked up as Ad Blue so the Aussies know which one it is!!! 
Reef:
TheBear:
Andyroo:
I never think to look for the fuel cap on a vehicle that’s new to me, until I’m about to pull in for fuel!Jesus, I cannot believe you said that, Andy!!!
Where else would you find a fuel cap than on top of the bloody fuel tank?? and a fuel tank on any truck…even a puddle jumper… isn’t hard to find!!!In all fairness to andy he said “any vehicle new to him” so that could be a car a van or a truck…and ive done the same thing …pulling into forecourt hanging out of door looking behind me to see if the tank/filler flap is on my side or not
ever tried opening the bonnet of a Ford Focus without prior knowledge - I know it aint a truck but imagine the embarresment when I asked the missus if she checks the oil and water, she said “whats that?” - with much mumbling and grumbling I decided to do a demonstration and couldnt open the bonnet for love or money. Had her in hysterics - not the desired result
loose wheel:
ever tried opening the bonnet of a Ford Focus without prior knowledge - I know it aint a truck but imagine the embarresment when I asked the missus if she checks the oil and water, she said “whats that?” - with much mumbling and grumbling I decided to do a demonstration and couldnt open the bonnet for love or money. Had her in hysterics - not the desired result
Heh, I’d had a day at work in my last job as chief tea-maker/ apprentice mechanic. I’d spent the morning finishing putting a new engine in a Transit, was feeling rather pleased with myself having not had to ask too often for help, and not broken anything.
Mate’s mum drops her car in for a pre-MoT check. One headlamp was out, so I went "oh, two minute job, no bother. Spent ten minutes looking all over the cabin for the release handle before admitting defeat. 
If it was a serious question, I would wager that he will never make a driver as long as he has a hole in his arse 
However on several vehicles I have driven the fuel filler has been hidden away in unexpected places like underneath the hinged number plate, under the bonnet or on one car you had to unscrew the rear light reflector to put fuel in.
Had it today…took the lorry in for repairs and jumped in the courtesy van. The fuel light was on so I drove straight to the sainsburys filling atation round the corner.
Pulled on to the forecourt and thought…“oh balls…I was talking about this just the other day on trucknet!”.
(LDV Maxis = Drivers side, just behind the door)
Did it myself tonight at Sainsbury’s - pulled up to the petrol pump and realised that the filler cap was on the other side.
…and I was driving my own car 
Yes, I know, I’m crap.