On main roads Low range is for those times when a Chinook with a sling coming towards you is a dream come true............. Cunningham and Toowoomba Range are just hills, many go for broke and hit a big hill at full speed, it doens't do a thing, best to hit the hill at a speed and revs that pulls, if you change gears at the right revs and start the hill in the right gear maybe one or two shifts all thats needed, change to revs/temp and your clutch is good and engine stays happy.... Tassie has some real doozies I am told, the thing many mistake is using the clutch they will ride it, in and out one movement done quickly, dragging only cooks thit and means you are going to be in the wrong gear, its even okay to jump a gear . each combination of gearbox/load requires a different method, so any suggestions as to what gear yoou should be in may not apply to your set up even if same tug.....
If a slow truck in front you change down, Ive even been in 1st but you must remmeber once in 1st you won't want to try to change up a gear unless the incline has dropped, the load on the running gear could be too much... If you are forced to stop then Low may be required to get going again but only about mid box.... Never drag the clutch or drive with a foot resting on it...
The smoky brakes is often because the driver is just a steerer or hasn't been shown......... Downhill you select the gear for the hill, be it an auto or a manual, bigger the hill the lower you go in the box, you can always go up a gear but never go down a gear once your over the crest, thats how runaways happen, you disconnect the major brake from the wheels, the engine.
Brakes get tapped to keep off top revs, if you have to keep foot on brake then stop select a lower gear and roll away again, on really steep down grades like Black Mtn down down Bega way, drop it right down, again tapping the brake alternating between van and tug braking also works allowing at least tug to drop temp a little bit....... If your brakes do smoke at the bottom of the hill don't stop, pull up when the smoke seems to have gone, they have then cooled down enough, stopping right at the bottom they may ignite and thats it all over red rover............ at night you may see them glow, don't use water, the drums could explode... and dry powder just dries out and become a combustable source.
When I'm at top off TWB Range I would roll over the top in 2 or 3rd in my 6 speed Colorado, 3rd or 4th in the Jeep (8 speed) and wishing I had a Jake Brake, just like my Truck with exhaust brakes, 40kph going down, I find 40 is a nice downhill speed on moderate hills, bigger mongrels I'll be 20Kph so if it tries to run I can pull it back... Time has shown to me 40k at most, really big ones 20 or less, you need to be able to stop dead with one good stab of the brake, more than 2 and you may not have any brakes.... Having had the odd runaway with gears poping out or Jake fails Ive tested the theory.... even one foot on gear shift other on brake, laugh now but not at the time.
Ideally I like to go down a hill towing not using the brakes and if I do only a few times .... Cooyar Range I rarely use the brakes and its a short sharp bendy drop, a great spot to keep the skill honed.....