Jump to content


Photo
- - - - -

20" vs 17" tires ?


  • Please log in to reply
15 replies to this topic

#1 penner

penner

    Senior Member

  • Members
  • 188 posts

Posted 17 January 2019 - 07:35 PM

I currently have 8 ply 275/55/20" KO2's on my truck. Considering swapping out my 20's for 17's and going for a less aggressive tire. I do next to no off roading ,a lot of backroad driving and mostly highway driving since the truck is my daily driver. Couple of questions. 1- Would there be much /any difference in the ride with the higher sidewall ?? 2- If I do the swap, any recommendations for tires? Maybe it's just me , but the KO2's seem to throw a lot of gravel. Our truck is a 2017 Z71 Silverado 1500 with a 2018 ATC Ocelot shell (72"wide) with a few mods. Thanks. Glen.


  • 0

#2 Wandering Sagebrush

Wandering Sagebrush

    Free Range Human

  • Site Team
  • 10,589 posts
  • LocationNortheast Oregon

Posted 17 January 2019 - 08:39 PM

Glenn, I think you would get a slightly softer ride (maybe). I like Cooper Discoverer AT/3s. I have them on my F350 and as of this morning, on my Ranger. Somewhere on ExPo there is a tire thread, I believe it was by Jonathan Hansen, that did a tire comparison. The Cooper was deemed the best tire for back country and road.

WS
  • 2

I am haunted by waters


#3 klahanie

klahanie

    Senior Member

  • Validating
  • 932 posts
  • LocationSW BC

Posted 17 January 2019 - 08:53 PM

Given the same overall diameter and tire type I'd expect with a 20" rim less "roll" or sideways flex when cornering on pavement. And with a 17" a softer ride on irregular surfaces. If you air down for gravel I think the 17, having more sidewall height to compress, could give noticeably more dampening.


  • 1

#4 Wandering Sagebrush

Wandering Sagebrush

    Free Range Human

  • Site Team
  • 10,589 posts
  • LocationNortheast Oregon

Posted 17 January 2019 - 09:24 PM

Found the review...

https://expeditionpo...meets-the-road/
  • 0

I am haunted by waters


#5 smlobx

smlobx

    Lost again

  • Members
  • 1,529 posts
  • LocationNorth Carolina

Posted 17 January 2019 - 09:46 PM

First, let me say that I have a high regard for the Cooper tire. We used it in Africa earlier last year and in driving over 2000 miles off-road in some very rough terrain our convoy of four Land Cruisers only suffered 2 flats. The Acacia thorns are very tough!

In the article mentioned above they left out one very important consideration and that is the weight of the truck fully loaded. It's one thing to test tires on a 5000 pound Jeep and a whole other beast to test it on a 8-10,000 pound truck camper.

IMHO when you are in that weight range you need tires with very robust sidewalls and E rated tires are almost mandatory. Our truck came with Michelin LTX AT2 and for a general tire used as described by the OP I would say that this should be considered. I recently upgraded to Toyo AT2 tires that were about 20mm wider than stock that allowed which also gave me more carrying capacity and perhaps better off-road grip. Time will tell.

I will also agree with above that if you plan on airing down 17" tires allow you more flexibility. Have you considered 18" wheels? There seems to be more E rated tires in that wheel size and might be a good compromise...
  • 0

Eddie
KO4CPL

 

Travel light. Travel far. Travel safe.


#6 Taku

Taku

    Buffalo Rockface

  • Members
  • 757 posts

Posted 17 January 2019 - 10:07 PM

Have an 05 Tundra with an Ocelot. Ran Michelin LTX AT2's for almost 60K and no problems. Switched to KO2's for the beefier sidewall and different tread pattern. They definitely pick up more gravel and are noisier. Traction is very good even driving Teton Pass in the winter. If you are going to use for a daily driver with the camper on I would go for the E rated Michelin's.


  • 0

2005 Tundra  2013 Ocelot    "Ridiculously comfortable"

 

2021 Tundra 2022 Cougar Shell Built Out  "Even more ridiculously comfortable"


#7 Ace!

Ace!

    Senior Member

  • Gone Traveling
  • 530 posts
  • LocationSo. Oregon

Posted 17 January 2019 - 10:46 PM

I would definitely check tire sizes of several good brands in several sizes or ranges of sizes you might use, then determine what size wheel works best.

 

Here's how it works, reiterating other posts above, the smaller the wheel the taller the sidewall for the same overall tire height.  Sidewall allows for more flex, which on the road translates to more roll when cornering.  Taller sidewalls "feel" less responsive when cornering.  They also allow for more flex when going over "bumps" in the roadway, which translates to more cushioning effect.

 

The reverse is true as you go up in wheel size/less sidewall height.  So, if you feel like you need more responsive cornering you'll want to stay with 20" wheels, but you'll feel more of the road while driving, both seat of the pants and through the steering wheel.

 

Generally, if the overall tire height is the same, the taller sidewall will ride better but be less responsive.


  • 0

#8 iowahiker

iowahiker

    Senior Member

  • Members
  • 487 posts
  • Locationiowa

Posted 18 January 2019 - 01:02 AM

We have LT245/75R/17 load range E tires from the factory for 110,000 miles, BF Goodrich AT's (not KO2's).  We are on our second set and obviously satisfied.  The first set were replaced after 75,000 miles and were in good condition (we wanted deeper tread).  Our loaded and wet weight is around 7500 pounds and handling/ride is perfect (unleashing the 5.0 liter double overhead cam V-8 on a curvy mountain climb got a thumbs up from the motor cycle following us at the top, with the camper on).  The door tire pressures are 60 psi rear and 55 psi front and we like the loaded ride while the empty ride is harsh at these pressures.  Picking up rocks is not a problem.  My brother-in-law's truck came with similar LT tires but no payload package and his door sticker tire pressures were 35 psi at all four corners.

 

The P rated BF Goodrich AT's (not KO2's) had groves in the outer tread races while the LT rated AT's outer tread races are almost solid.  Those solid outer tread races increase tire life and handling and reduce noise at the expense of some traction.  My opinion is a truck with LT 75 profile tires (stiff sidewall), solid outer tread races, a solid rear axle, a heavy duty spring pack (we have the payload package), and sufficient air in the tires handles well (whats left to move sideways?).  


Edited by iowahiker, 18 January 2019 - 01:02 AM.

  • 0

#9 penner

penner

    Senior Member

  • Members
  • 188 posts

Posted 18 January 2019 - 12:12 PM

Thanks for the replies. My camper is only on the truck for 4-6 weeks a year and they are high mileage trips. I'll have to see what I can get for my tires and rims , that will help make my decision easier. Have a good day. 


  • 0

#10 XJINTX

XJINTX

    Senior Member

  • Members
  • 552 posts
  • LocationEddy, TX

Posted 18 January 2019 - 12:55 PM

Following... timly post for me. I am running 20" BFG KO2's on my F250 with a Hawk. NO COMPLAINTS actually second set of BFG's KO and now KO2. I am moving downsize this summer. I ride with others with same size setups and "most" are running 17's. When we air down they are at a big advantage and each love their setups. Unless convinced different I am looking at 17's with new BFG's


  • 0




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users