I'd think front runners would work OK.
IIRC when I talked to M&H about mine, they told me not quite... but I've got about 3200 lbs on the fronts ~ 1600 lbs each. on a 5000+ lb total.
At 1375 each or 2750 total on the front's now that sounds more workable.

 

isnt the m&h load rating only in the 900 lb range? i was just looking at these the other day.

 

I called m&h tire co. And spoke with John and he said the load rating is 1320lbs for that tire

 

edit
Ok got to see a set of the M&H 4.5 28 17's today
it says 1325 lbs at 35 psi max load.