I've been running 1.5" adapter spacers for over 2.5 years now and have never had an issue. I've run them with my 17" and 20" rims both with 35" tires. I pull flat bed utility trailers all winter and a 20' boat all summer and as long as you torque them when you first install them and check them whenever you rotate your tires they are fine.

Some will tell you only to buy hub-centric adapters, they might be right and I am sure they are great if you can afford them but I just have some nicely machined cheap ones off of eBay and so far they have not caused me any issues. With factory offset rims I think they work great giving the truck a nice stance.

 

Should they be safe on a 2wd?

 

You will be alright. I know there are a few guys on this site and a buddy of mine that run them with full lift kits, 35" tires and large aftermarket rims and have had no problems.

 

Don't take what I said the wrong way. You can run them without problems but don't go excessive on how far you kick them out. Like I said, with stock wheels, you will be sitting similar to the backspacing on an aftermarket wheel so you should be fine. What would worry me is getting aftermarker wheels on a 2wd and then having the spacers on top of that. Your truck is also a newer version which I'm assuming have bigger bearings from mine because the last time I saw the rotors on the newer style they were much larger.

 

I agree. I wouldn't go any bigger than 2" with any rim.

 

just to add to this thread. I added a set to my 2wd a week ago. Before you install them the front lugs will have to be cut down a 1/4" or more if you install 1.5" adapters. I ran into this problem and fix it right up. Just giving you a heads up.