threshold wrote: It was climbing on a sandy chewed up hill, Was climbing well but kicked back to 1st and lost momentum.
Ahh, ok, that makes sense.
Here's my take on what was happening.
With the car at the edge of kicking down in 2nd low, you were putting the least possible torque to the wheels to do the job. This was perfect because you were obviously at the limit of traction. When the car kicked down, torque at the wheels increased dramatically. This broke traction, reducing engine load, pushing the revs higher at which point you were denied.
Is the car a V6? these are notoriously peaky and revvy motors in my opinion. You would probably have had the same problem with a manual.
Here's the cause of your problem - once a tyre spins it looses nearly all its traction. it's only in a tiny fraction of situations where you can accelerate a spinning tyre and increase traction.
A decelerating tyre gradually gains more traction the closer to the cars ground speed it gets
high engine revs and low gears result in a lot of inertia in the driveline which makes the tyre insensitive to the terrain.
If the car is close to kicking down back waaaay out of the throttle. it might not kick down, and if it does, you'll have greatly reduced the torque and inertia at the wheels. You're trying to match wheel speed with vehicle speed, so if it kicked down at 3000rpm in second, it's probably only 4250rpm in first that's required to hold the same speed, but to match the torque at the wheels, you'll only need to be brushing the throttle.
Alternatively, pull the car back to first, get the revs right up but on a very light throttle. if you need to build momentum, give the car second and mat it. it might not use second but if load drops, it will upshift and you'll get all the wheel speed if you need it.
Autos aren't easier to drive off-road than manuals, but they're much, much more effective, you just have to learn how to use the slip in the converter to your advantage.
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