Here's a tip I read about years ago - for maximum traction for those of you who have a 2WD drive motorhome or tow vehicle with a regular differential (one that doesn't lock up): In poor traction situations use 2nd gear to better keep both rear wheels pulling. This prevents or greatly reduces - the tendency for one wheel to stop spinning while the other wheel gets all the axle torque.
I starting using this trick in my PU when going up our steep driveway in wet weather. It indeed does help keep one rear wheel from spinning with the other doing nothing.
It's the application of overly strong driveshaft torque from the engine that switches a standard differential into allocating torque to only one wheel. A low gear plus heavy gas pedal application triggers this. Use of 2nd gear plus a gentle throttle helps keep both wheels engaged and pulling via a standard differential. I'm guessing that this technique may also help in soft sand situations.
