SheepOfBlue

So I cannot drag a hoof until after Grattan as I hoped. The center is at the wear bars (or below ) and it might be raining on the way up so I think that is being dumb.

My truck is a 2000 Sierra and there is two tires listed a 235/70-16 or a 255/70-16 The 255 is listed as an option and is what is on the truck. I am thinking of going 235 for less side wall height to flex. Is there any reason why not?

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ND4SPD

235/255 is the width of the tire, not the height; 70 is the height of the tire. If you go on lower profile tires your ride will be harsher.

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luvtolean

I put 255s on my D-Max, it's much better. I think I have Pirelli Scorpions IIRC.

It's a truck, get the sidewall flex.

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SheepOfBlue

I knew that

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luvtolean

But, you were still right in the wrong way.

The 70 is a percentage of treadwidth, so a 255 is taller.

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SheepOfBlue

My truck is really a tow vehicle. That is about all I use it for. I figure the loading might be better on a 255 but sway may be worse (though my damper stopped that pretty much) I even considered a camper shell to expand storage and improve aerodynamics since I don't use the back to haul dirt and such when not towing (though I might get rid of it next year so am doing nothing).

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seamus

Inflated to the proper street pressures, the flex isn't going to be extremely noticeable to the assswaybar.

Check the load ratings on the 235 and 255. If the load rating is enough, you can put the 235s on it. You may even see some gas savings.

With the shorter sidewall (lucky error in your first post) you may notice four things:
- Slightly less sway
- Slightly harsher ride
- Slight speedo/odometer inaccuracy (or correction) due to the smaller tire height.
- Slight increase in rpm at speed

There's a formula for calculating rpm at speeds (and vice versa) but I'd have to look for it. I have it written down somewhere.

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luvtolean

Gas savings would come from the 255s, which will travel further for each driveshaft revolution.

235s are stock so they will work.

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ND4SPD

But you're also increasing contact patch which translates to more resistance. But then again, I'm no engineer.

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seamus

My bad. Forgot to figure in the tire size on that one. I only figured the friction difference in.

__________________
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Richard Herald, The Gentle Giant

The nation that makes a great distinction between its scholars and its warriors will have its thinking done by cowards and its fighting done by fools.
--- Thucydides