I had my 2013 NVP3500 converted to 4WD by Quigley in January 2017. I wanted to spend a bit of time with it before giving my review, since I don't drive it very much (17K miles in 3.5 years). Quigley performed my conversion very quickly, my vehicle was in and out in under 2 weeks. They did say that was kind of unusual, I just happen to get into the build schedule at a good time. Let me say right up front that Quigley does a very professional conversion, everything looks just about OEM. Quigley's customer service is also top notch, they keep you informed about the build and they attend to all the little details. Your vehicle comes back to you all converted with no signs that someone has been doing major surgery on your vehicle, ie. no mechanics tracks are left. The only thing that I could "ding" them on was pretty nit picky, underneath the van I found that they didn't clip off the tails of the wire ties when they secured the transfercase wiring. I could hear the tails of the wire ties rattling up against the heat shields, so 1 minute w/ a pair of sidecutters and all was pretty much perfect. I am very pleased with the fit and finish of their conversion. Now on to the driving experience. When I drove my van home from Quigley ( which is only 40 minutes) I could not tell any difference in the van. Running in 2WD, I could not even tell that anything underneath was different. No vibrations, no noise, nothing. I drove both highway (up to 75 mph) and local back roads and the van felt utterly the same as it did before the conversion. When I got home, I took the van of the pavement out onto my yard and fields. The terrain was wet and muddy grass. Pulled the lever into 4WD and off she went. The van was transformed from a vehicle that would get stuck on anything that was even slightly slippery to a vehicle that could climb wet grassy, muddy inclines with no problem. I could now easily retrieve my trailers that are located down near my stream and tow them out through wet sloppy terrain. Utter night and day difference in tractive capability. We had a late March snowstorm this year that dropped 10 inches of wet, heavy snow on our roads. Early that morning, before the snowplows got to our roads, I took the NV out for a snow test ride. I used to get stuck in my driveway on a couple of inches of snow before the conversion. Now, with 4WD egaged, I headed out into 10 inches of wet snow that was unplowed. I drove all around my area with no problem, uphills it just claws it's way through the deep stuff. I was very impressed with the ability that the van has now, no more fears of getting stuck if I take the van off the pavement. Only thing that I could tell when in 4WD, was a slight whirring sound from the transfercase when driving through the snow. One caveat I should mention is that I do not have the stock Firestone Transforce tires, I have a set of BF Goodrich All-Terrain KO2 275/65-17 tires, so they definitely help the tractive capability. So all in all, I am very pleased with the conversion and feel that the addition of 4WD has made my NVP much more versatile for use as a recreational/adventure vehicle.
Now one other note, since I am a lifetime gearhead and a vehicle dynamics engineer, I always find myself investigating/repairing/modding any of my vehicles. This led me to investigate as to whether or not the Quigley 4WD conversion was just a single speed (4WD HI only) or (4WD HI and 4WD LOW). Using the interior lever you can only engage 2WD and 4WD HI. There is a "blocker" bracket mounted to the t-case that prevents the lever from moving past 2WD toward Neutral and then to 4WD LOW, also the interior lever will bottom against the floor before the lever can move the t-case past Neutral. But, if you go underneath the van and disconnect the linkage to the t-case, you can then manually shift the t-case lever into Neutral and 4WD LOW. I tested this. I went underneath the van, disconnected the linkage, shifted the t-case lever into 4WD LOW. I started the van, noting that the 4WD indicator light was now illuminated, and then drove out onto my driveway. Sure enough, the transfercase was in 4WD Low Range ( low range is something on the order of a 2.76 : 1 ratio). You could easily tell since the van was now moving slowly when the engine revs were up. So, the t-case is definitely a 2 speed box. So, an enterprising person could modify the linkage such that you could engage the 4WD Low from inside the van, Just saying, since doing this would likely void your Quigley warranty. But for all those wondering about this issue, yes, it is truly a HI and LOW range transfer case. And we know from others on this forum who have the Advanced 4WD conversion that the issue with "going into limp mode" due to transmission / wheel speed sensor mismatch while in Low range can be avoided or compensated for.
2013 NV3500 passenger
Quigley 4x4, Aluminess front bumper