Certainly straining the engine is a small part, and easily controlled by not going with the gas pedal all the way down. What I found most disconcerting as I neared my load limit was the feeling of being pushed while on long downhill sections. The only way to control descent is by putting the truck into a lower gear, and letting the engine spin. With a small engine, there isn't as much resistance against over-speeding compared to a bigger block engine.
There really isn't any way that will last for a long down hill other than engine back pressure, you will want to brake so much, and you just can't use your brakes like that.
