00bolt

this is going to sound like a silly question, but I am trying to figure out how much taller/shorter a new tire would be compared to my old worn out tires.


I currently have 285/65/20 tires. When I do a little calculator online, it says they are roughly 34.5" tall. But I am thinking about buying 275/65/20 next time because they are a few hundred dollars cheaper. But the same calculator says they are only about 34" tall and I would lose 1/2" in height.


But I am wondering if in the end, the truck would still sit about the same. Since my current tires are pretty bald and need replaced, have I already lost about a 1/2" in tread height? hope that makes sense.

techrep

iTrader: (1)

the three-digit numeric portion identifies the tire's "Section Width" (cross section) in millimeters.
Typically following the three digits identifying the tire's Section Width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.


so your 275/285 is tire width not height

00bolt

I know, but the 65 is the ratio and since the width is not as wide, the ratio makes the overall tire a little smaller.

techrep

iTrader: (1)

1/4" of ground height.. tread depth is measured in 32nds of an inch .. so you would have to see what a new tire that your are planning to buy has for a tread depth.. like my Nitto trail grapplers come new with 21/32" tread depth

00bolt

so essentially a brand new tire vs. used bald tire is about 1/4" taller?

techrep

iTrader: (1)

same size yes..depends on what tread you are looking at All terrain or Mud terrain

00bolt

BF Goodrich AT KO2

techrep

iTrader: (1)

Those come with a tread depth of 15/32" so...just shy of a half inch of new tread.

00bolt

perfect, that's information I wanted. so in theory a completely slick worn out tire would be nearly a full inch overall shorter than a brand new one. of course, mine aren't quite that bald. but I am thinking the little bit of height I may lose in going to the smaller tire, may be gained right back by getting new tread anyway and be a wash. I know we are only talking about half and inch to an inch and sounds silly, but I just put on a leveling kit and adding a 1" body lift and just trying to get an idea of the overall height is all.

Dirttracker18

Tread depth on that tire is 15/32 when new. That is slightly less than 1/2" in total tread depth. Assuming significant wear leaving 3/16 you would be at a difference of 11/32 so lets say 12/32 to make it easier. that is 3/8 of an inch of lost tread so your truck is only 3/8" closer to the ground with a wore tire of that make.

Difference between the 285 and 275 is 1/2" total meaning that would make your truck 1/4" in actual height as compared to the current 3/8 worn out.

With those numbers your truck would actually sit 1/8" higher with the new smaller tires than current.

Overall, it is only a 1/4" difference in truck height with both tires being new, negligible and nothing to be concerned about.

However, personally I like to to slightly bigger than slightly small in a truck, especially with a level and body lift, but that is just me