Originally Posted By: IndyIan
Originally Posted By: hattaresguy
The ZF in my truck is always in the right gear, or if its caught quickly corrects.
GM needs to move one generation ahead, the newer auto's are fantastic.
I have a manual mode but never use it, its a waste of time the transmission is always doing what I would have done anyway.
Hills are a perfect example. My buddies Suburban will race to 6th pulling up a steep hill we have only to lug and downshift. My ZF stays around the middle maybe 5th all the way up at 3k, and won't up shift until the crest. It will also drag that gear down the other side, while the Suburban is again in top gear and your on the brakes.
So how does the auto know when you don't want it to add some engine braking?
Our new CRV loves adding engine braking in a lower gear too, but I nearly never need it, so now I have to hit the gas to make it upshift??? The old dumb autotrans were atleast predictable. Atleast I can still pop in N to get some free mileage down the hills...
Automatics still have a place of course, but until they link it up with a camera, Gps, and road data including speed limits and slopes, it's going to be in the wrong gear very often... That's just a fact of it guessing what it should do, based on a fraction of the data it needs to make a smarter decision.
I suspect it gets inputs from the trucks other systems:
Brakes
Engine output
driver inputs ie steering, throttle, braking.
It also must be able to figure out the angle that the truck is at because it certainly seems to be able to figure out when to downshift and when not to.
It also has a fairly intelligent learning curve based on historical data of driver inputs.
On a long hill if you give it throttle input it won't do much, but if you start to brake the transmission will jump right in line with what you are trying to do. Screwing with it by putting it in neutral down a hill is an awful idea.
The biggest thing I have had to learn is to stop lifting to get it to up shift. I'm so used to older transmissions where you could lift and kind of dictate the up shifts. This gear box doesn't respond to that you just slow down.