I'm ordering a new 4X4 1500 Laramie that comes with 20" wheels. I have a two axle enclosed trailer that weighs about 4500lbs. I pull it a couple times a month. I'm planning on getting the 3.92 rear end. But not sure if I should order the 17" wheels or not. What would you do?

 

Well it's personal preference but if you're worried about towing capacity the 17's will suit you better. They are lighter and typically larger rims are not meant to be under heavy loads.

 

Go with 20's!

 

Towing with 20's for years... No problems and looks way better!

 

You should be fine with the 3.92 and the Hemi. I have always gotten the 17 for their smoother ride and better bottom end performance, but my 20s on the 09 ride nicely. I have the 3.55 with the sport package because I could not find a sport with the 3.92. You technically will have a higher tow rating with the 17s, but unless you are pulling over 9,000-10,000 pounds, you will be fine with 20s.

 

I personally think the rcsb trucks look better with 17's, as 20's on those trucks look a little too big for me. That's personal preference, however.

The logical reasons I prefer 17's are that 17" tires cost less to replace and the 17" setup has less unsprung rotating weight. Also, drag radials are easier to find in a 17" size than a 20", if I should ever decide to try those.

 

They have improved the technology in 20 inch tires for trucks to provide the same towing capacity as the 17" wheels in the last couple of years. As well as great ride quality.

You will get a smoother ride from a larger sidewall tire but no real capacity challenges with going with 20 inch wheels. 17 inch tires are slightly cheaper to replace but by the time you get to the point in which you need to replace them there will be more 20" wheels on the roads and the prices will be identical for replacing them.

If you do go with the 17" make sure they are aluminum and not steel. If not your unsprung weight will be about the same as running the stock 20" wheels and going with the 17's won't save your anything on that front.

Your only capacity constraint is the trucks frame.

 

When it comes to towing, I don't think dodge is rating the 17" wheeled trucks higher than those with 20's because of wheel strength. I think it's simply because the 20" tires are taller and reduce the effective gear ratio. Same reason that all else being equal, trucks with 3.92's are rated to tow more than those with 3.55's or 3.21's.

 

I like 17's on trucks. 17's look way better!

On another note, if you ever go off road the sidewall flex on the 17's is going to be better for rock crawling, etc.

 

This is true, Bigger is better for rock crawling and off roading.

The effective rolling diameter of the wheels on 20's and 17's are about the same due to the increased sidewall on the 17's so that's not going to make a difference.

Towing is going to be based on your rear end choice not the rim size.