18" or 20" wheels

[grayfox]

I'm currently working on specs for a new 3500HD HD GMC Sierra. Should I go with 18" or 20" wheels.

Pros and cons please...

[OldCoot]

Originally Posted by grayfox

I'm currently working on specs for a new 3500HD HD GMC Sierra. Should I go with 18" or 20" wheels.

Pros and cons please...

Strictly in the towing mode, the 18" are superior. Gas mileage wise, the 20" are better.

[MillerTime]

The wheels wont make a lick of difference, the stock tires will be roughly the same overall outside diameter regardless. The 20" tires will, cost more to replace. Sometimes they will have a different load rating. (Prior to the 2015, if you got a single rear wheel 3500 you could only get the 18" (as an option instead of the 17s), as the tires on the 20"s , optional on the 2500 were not rated high enough).
I didn't think they changed wheels for 2015, as drive train and chassis is the same, but I don't know for sure.

MillerTime- Future Sabre Handler!!

[MillerTime]

Oh the 20s look nicer!

If you are building on line, it will not let you select certain options if you chose a certain chassis or other option.
Like there was on the 4.10 gears. If you selected a diesel engine, than you got 3.73 gears. If you then select the 4.10, then it will kick it back to the 6.0 gas, as that is the only way to get that gear option. ( this was in tbe '14 hds, I havent looked on the 15s yet.
It was doing it the same way on the 3500s on the 20" option, it wouldn't be available unless you picked the 2500.

MillerTime- Future Sabre Handler!!

[MillerTime]

Just checked, 20s arnt available factory on a 3500 srw. 18s only available option. Steel or aluminum.
On dually, 17s in steel or aluminum is only options.
And the 3.73s are only available gears for diesel still too.

[grayfox]

According to my dealer 20's are available on 2015 3500HD's SRW and he had one on the lot... so he says ???

[MillerTime]

Originally Posted by grayfox

According to my dealer 20's are available on 2015 3500HD's SRW and he had one on the lot... so he says ???

Well I was going off of factory options. The dealers can always take the wheels off of a 2500 and put on the 3500, or even aftermarket. I'd check the tires and the door jam sticker to figure out if they swapped them. Also check tire load rating, it may be less than what the Individual axle ratings are if they did swap them.
And you will know more about available options and forced options, than the salesmen if you look at the GMC site.
Best to ya!!

[Cajun Po-Boy]

Originally Posted by OldCoot

Strictly in the towing mode, the 18" are superior. Gas mileage wise, the 20" are better.

20's for looks...18's for functionality

[grayfox]

Thanks for all the responses. Kinda what I thought so it helps to see other comments and ideas . I think the 20's look better in the big wheel well opening as to performance I'm not all that worried about it. The other thought I had was ride quality with the 20's and the somewhat low profile looking tires.

[RhoZeta]

"E" rated 20's can carry the same if not more than 18's depending on brand so functionality, capacity wise, is a non issue.
Plus 20's look waaay cooler!

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[MillerTime]

My nitto 18s are rated for 4080 lb each. That was the highest I'd ever seen on an Lt tire, or an st for that matter.
But if I could get a new 3500 truck with 20s with a high enough load rating I would. But if I did buy a new one, it would probably be a dually, so 20s are out.

Not much difference in ride wheel wise. The tires are where the difference is....its the stiffness from the load rating and tire make up. My 18s are ROUGH, but DWs p rated 20s are super smooth.