Best size truck tire for towing

[DeeBee]

Is there a best size tire to have on a truck for towing a travel trailer? Would 17 inch tires be ok...or am I better off with 18's? Any insight would be helpful.

[TWP723]

What vehicle do you have and what are you towing?

[DeeBee]

We have a GMC Sierra are looking for a newer one to pull our 5300 lb (empty) travel trailer. As we look at newer used...we see some have 17 inch and some 18 inch. Want to know which would be the best choice.

[TWP723]

Not a huge difference between the two looks. You can have an 18 inch rim with low profile tires and a 17 inch rim with high profile tires and it's almost unnoticeable. Normally, 18 inch tires cost more but not always. Both sizes can be bought as LT tires with load range E which I'd encourage. 18 inch tires have a higher index (higher load carrying).

[Jerry713]

I would stick with the size that came on your vehicle originally. Changing the tire size changes your rear axle ratio among other things. If you increase your tire size you decrease your rear axle ratio essentially reduce the amount of towing power. Granted going from 17" to 18" in the same diameter tire it's not a lot and may not be noticeable depending on your tow vehicle and engine but it could.

[JFlightRisk]

Tire dimeter change will affect your speedometer also, and you'd have to get that recalibrated. Best to go with whatever is on the truck, it'll be just fine.

[TWP723]

The OP is buying a new truck. They just wanna know what wheel to look for as they look around. But yes, always keep the original tire size that came from the factory.

[RAMPANT-RVer]

I always say to stick to factory size. I know your only talking an inch, but when towing something heavy, it can change a lot of things for the worse (traction, steering, suspension, braking and weight ratings). I do recommend going to a 10-ply tire in your factory size. It increases weight loads and are more puncture resistant. I did this on my truck and trailer tires. Hope this helps!

[mokurt]

I would think that a new truck that has a factory tow package would have the proper size wheels and gearing.

[mrmom]

Not much difference between them, I would prefer the ones that have the 18" wheels.