LT all the way, and if it is a heavy rig like a 3/4 or 1 ton, the E rates are the only way to go. E's hold up so much betetr than Ds.
Alos, I learned something interesing. I had a set of D rated 285/75R16s (16x8" wheels) on my 2002 Dmax. They gave it 7 3/4" clearance under the rear diff. My 2009 came with 265/70R17 E rated tires (17x7.5" wheels), which are nominally 1.2" shorter. This should equate to .6" less clearance under the rear diff than with the 285s. However, the 265/70R17s give me 7 5/8" under the read diff. In other words, the D rated 285 squished down almost a 1/2" more than the E-rated 265s.
That is most likely because the Es are a 80 psi tire while the Ds are a 65 psi tire. So in this case, all the 285 Ds did was give me more rolling resistance without a significant increase in ground clearance over the 265 Es.
