Quick one for you… How will I know if the wagon I am driving has got an exhaust brake / retarder? I am very new to this game and am doing the agency thing. Have only driven a couple of ERFs ECT IIs so far and found myself scooting down the motorway at over 65 mph once or twice with brakes smoking on long downhill sections. Not good for the nerves !
Scania. Far left switch. Make sure it is ‘On’ unless icy.
Volvo. Two or three position switch immediately above gear knob. Leave in ‘Mid’ position for normal use.
Mercedes. Stalk on right of steering wheel. Normally selectable ‘1’ or ‘2’
ERF, foot valve on floor.
The variations are endless, and can only be determined by reading the manual. If only they were actually available. 
One of my pet gripes, is that I can buy a mobile phone off Ebay, and then download a full manual from the manufacturers site. Yet, given a vehicle costing umpteen grand from new, once the operating manual has been lost/removed, the only course for replacement, is to purchase one. A situation not exactly conducive to the promoting of road safety and the protection of the road using public.
First suggestion - ask another driver at the client. They’ll probably be able to tell you.
Otherwise…
Scanias usually have an automatic exhaust brake which you switch on with a rocker switch on the panel to your left, and it engages when you press the brake pedal. I’ve also driven a Renault 7.5 t which also had the same setup.
MANs (and also probably ERFs since they’re pretty much the same thing nowadays) usually have a little button located on the floor underneath the steering column - basically, put your foot where it’s just about to go on the clutch, and the button is behind your heel.
I believe that some trucks also have a button/pedal somewhere in that area as well, but I’ve never found one.
Some trucks have them (or possibly retarders) on one of the stalks.
It’s been so long since I’ve been given anything that isn’t a Scania that I’ve forgotten…
Of course, even if you don’t have an exhaust brake, you can control the speed by changing down a bit more.
Thanks guys, the first ERF I drove had a foot switch, which I trod on as I was fiddling about before setting off, and the engine stopped. I thought this must be some sort of emergency engine stop - if only I had known. The second one had a blanking plate in the same position, I guess this must have been an option.
my guess is if the engine stopped the exhaust brake was probably faulty. ie. closed too much and blocked the exhaust.
I would’ve thought all trucks came with them as standard now?
Ivecos have a switch on the floor then a dash switch to change between, manual with the floor switch, auto with the foot brake or auto when you lift off the gas.
dennisw1:
my guess is if the engine stopped the exhaust brake was probably faulty. ie. closed too much and blocked the exhaust.
Quite a few years ago I drove a 7.5t Renault (E reg) and I’m sure this was the only and therefore correct way to turn off the engine.
when i first started driving 7.5 tonners i pressed the button on the floor on one lorry through curiosity…(had an idea what it was, but never used one) lorry then slowed right down and started pouring smoke from the back end…then had to pull over because of smoke and unable to get above twenty MPH.
What was wrong with that?
Nothing that’s the smoke screen button for when you’re being tail gated 
dennisw1:
my guess is if the engine stopped the exhaust brake was probably faulty. ie. closed too much and blocked the exhaust.
No. It normally also shuts off the fuel.
robin hood:
when i first started driving 7.5 tonners i pressed the button on the floor on one lorry through curiosity…(had an idea what it was, but never used one) lorry then slowed right down and started pouring smoke from the back end…then had to pull over because of smoke and unable to get above twenty MPH.
What was wrong with that?
sounds like the exhaust brake was stuck on,
Krankee:
Volvo. Two or three position switch immediately above gear knob. Leave in ‘Mid’ position for normal use.
Or may also be a stalk on the right side of the steering column. Five positions ranging from ‘A’ (automatically comes on each time you lift of the accelerator) through 1, 2, 3 (different amounts of retardation, 3 not advisable if running solo as you are likely to be peeling your face off the windscreen) to ‘B’ which on the auto box blends the brake and gears to help maintain a speed on a downhill.
So would you select 1, 2, or 3 based on the gradient you’re on at the time, or preselect one in advance, based on how much load etc. the truck has e.g
fully loaded/part loaded?
I remember the vehicle that i trained in had one, but that was just a button
on the floor.
sidan:
So would you select 1, 2, or 3 based on the gradient you’re on at the time, or preselect one in advance, based on how much load etc. the truck has e.g
fully loaded/part loaded?.
Pretty much. I leave it on the A position all of the time then flick it to 1,2 or 3 as required for a descent. If you flick it to 3 and it is too much just click it back to 2, or even 1. With the auto box and a steep gradient I will use the B position but that isn’t often needed. You wouldn’t be advised to leave it on 1, 2 or 3 all the time, just use them as required.
Just a little point, Volvo say the stalk should be in the ‘Off’ position, the one before the ‘A’, when starting the engine. The same applies to the 2 or 3 position switch on the dash for those models that have them.
Stralis - The exhauster is on the stalk to the right of the steering wheel, it has a brake symbol - (O) - on it. The furthest position towards the dash is “Off”, then there are two “On” positions, the strongest being furthest towards the driver.
It’s the type which automatically comes on when you lift your foot off the throttle as well as when you brake - brilliant on hills. I use the strongest position when I’m loaded, the gentler one when I’m loaded empty or loaded light, and off when I’m empty. Holds me back down Windy Hill (M62) with 44t on no trouble at all.
It can be quite fierce, especially if you use Automatic mode on the gearbox, as it’ll drop itself several gears for maximum effect if you brake more than very gently. That’s one of the many reasons why I never use Auto mode in the wet! 
The upside to this is if you need to stop in a hurry then flick into Auto and it’ll anchor up impressively.
Be warned also that if you brake sharply when it is switched off, it will still come on just before the ABS kicks in.
Like all brakes which work on the drive wheels alone, it needs to be switched OFF ON ICE AND COMPACTED SLIPPERY SNOW!!! Unit braking harder than trailer in skid-risk conditions = jack-knife waiting to happen. Obviously this doesn’t apply to rigids.
Ps. Afterthought…I pull mostly containers, hence the slightly strange loading descriptions above. Loaded = loaded box; Loaded Empty = empty box; Empty = no box. Sorry if I confused anyone with that! 
DAF is a button towards the top of the footrest on the left of the clutch.
Not much use though
To use any Exhaust Brake, the revs need to be high(different trucks have different rev ranges) to work efficiently,so its generally a good idea to drop a half gear or full gear,obviously depending on the gradiant.Even the DAF’s Exhaust brake works well when used in conjuction with the gearbox.
Loggo:
DAF is a button towards the top of the footrest on the left of the clutch.Not much use though
Tell me about it…
All it seems to do on these new 85 cf’s I drive is cut out the cruise, just as well i don’t carry much wait