19.5 rims

[maverick_935]

Possibly looking at 19.5 rims that are found on the Isuzu trucks. Will they fit the 3500 and allow you to put on truck tires for greater mileage?

[GMC D-Max]

Most likely they won't fit as a "direct bolt-on". Are they 8-lug? If so, they're probably 8 on 275mm bolt circle, and will require adapters. However, I don't know if 8-lug to 8-lug adapters are even available... 10 lug to 8-lug are common.

I'm looking to do this same conversion, but I'm machining my own adapters (I have 8-lug rims from a 4500).

Tires in 19.5 will be medium duty "commercial" tires, and are most commonly available in "G" load rating. They're going to ride quite a bit rougher than our stock "E" rated tires. Also, expect mileage to suffer due to the increased diameter and mass. I weighed one of mine (Goodyear G124 245/70R19.5 on Alcoa 19.5x7.5) and it's 115lbs. The wheel isn't the bulk of the mass, but the tire. This will have an adverse effect on braking performance and mileage.

[DmaxMaverick]

"Standard" 19.5" wheels won't fit without adapters. There are a couple mfg's making 19.5" wheels that fit the 8x6.5" pattern. True, they are normally medium duty tires, and "G" ply rating (14 ply) is the norm. A very hard tire, compared to light duties. They wear very long (about double, compared to LT's) if kept up to pressure.