If I am cruising around the small town with all the stop signs and the truck is unloaded, I leave it in Hi. If I have a load in the bed or I am pulling the trailer with the hoe etc, then I shift it into low while the trans is in neutral at the stop sign, then go. Once the trans is in 4th, I slack the throttle and click the switch and it rolls into high with usually not much of a hickup; every once in a while it will clunk ever so slightly.
If I get on a certain not so steep but long hill with a load, with the trans still in 4th, it will slow down and I wait till the revs pull down, then slack the throttle, flick the shift switch, then rev it up pretty good and it will go into low. This has to be done correctly and with a bit of precision, but it allows for shift.
Low is only good for a hair over 35 and it needs the hi range to get to the max speed of about 53 mph at 2500 rpm. Note: I am in Kalifornia where truck speed is limited at all time to 55 max. BTW same if you have your pickup with a trailer.
On my way down the highway empty and no trailer going to get gravel or asphalt, it seems I could use another gear, but when you come back to the job full it seems better with the load on the engine (same rev, just working is what I figure).
You can manually shift the trans, but the allison guys said it is better to let it do the shifting so I do that. On one or two locations where I know it may lug but not down shift till it is way lugged down, I will slow then click it down and then leave it there so it doesn't hunt, but that is cause I know that road and have tried it both ways. Once at the crest click it up into 4th and keep on going.
At the last flat before going down a hill I put on the flashers and slow and brake till it downshifts into a safe gear like 2nd, then I go on down the hill and if necessary hold the revs at 2300 to 2000 with the brake. Push to slow, then rest the brake while it climbs. I try to keep these routes to the minimum: too nervous. Thought about an exhaust brake to help on these occasions.
I guess you all probably know there is a tiny 2 speed gear drive electrically operated on the speedometer cable that is electrically paralleled with the shift motor on the rear axle.
Starting a big load on a hill with this truck is never a problem and other manual trans trucks will have clutch stink to do the same thing this does easily. With your two feet, you can crowd the brake and the throttle and creep ever so slowly while being guided into a tight spot.
My "sidewalk superintendent" is a retired over the road truck driver - he really wanted me to get a lot of speeds in a manual but I could not afford that to get started so I got this, the seller said a lot of men passed it over but talked to me about his experience driving it around the city (he was getting out of dirt and had his wife and daughters running cellphone stores). I am glad I got the truck and fixed it up cause I like it and it does real good for my work and my driving, and if I have to beg the missus to move it across town, it can be accomplished due to the auto and the power steering and power brakes (vac over hydraulic).
That's about how it drives: pretty easy.