Which rides smoother----single axle or tandem?

Single axle it absorbs half the bumps as a twin screw.

 

Disagree! Strongly disagree! Too many years of LTL where I was driving them both back to back.

Of course the biggest difference in ride isn't the number of axles, it's the type of suspension.

 

Strongly agree with most everything you said Big Don, but...
Also with two axles, the "felt" bump is reduced in half by having two axles
And when this arguement is beat to death, then try pulling a single axle trailer...now there is being beat to death..

 

never drove a single axle truck but i run with my front axle pulled up on my curtain flat a lot. it rides better. air ride of course

 

Tandem deffinetly rides better. I have driven trucks before and after they were cut down into single axles and they allways rode better as tandems.

 

BTDT, along with pulling doubles and triples with a single axle sprung day cab tractor, no air ride. sheeeeeeeesh.

 

i would have to say a twin screw.....plus air ride.

 

I would say wheel base length and suspension travel.

 

If you're talking about felt ride quality, a tandem axle feels smoother to me, loaded or empty, regardless of suspension type. Single axle tractors seem to buck a lot, especially when being chased by a near-gross 48' or 53', less so when pulling a pup or other small single axle trailer (or a set of doubles). Wheelbase does have a significant effect though, with a single axle sleeper being smoother than a single axle daycab (also applies to trailers). Suspension styles may influence this somewhat as well, though I feel that most air-ride suspensions are quite comparable given similar axle configuration (eg. tandem Freightliner vs. tandem Mack daycabs).

Smoothest I've ever personally experienced was a Pete 387 pulling 48' spread, grossed out at 80k. Choppiest was a single axle FL Columbia with a 53' grossing very near 65k. Sorry older guys, I haven't much meaningful time in a spring-suspended rig (a few forays into Brooklyn in a camelback Mack R model, ouch).
Of course, these are my own observations based on driving in metro NY/NJ/MA. Your equipment, roads, and loads will vary, as will your perceptions.