Sponsored

35x12.5R17 vs 315/70R17 - BFG KM3s - Need some clarification

Midwest22

Well-Known Member
First Name
Scott
Joined
May 11, 2018
Threads
10
Messages
134
Reaction score
153
Location
So Cal
Vehicle(s)
2018 JLUR
Sadly Ive spent a ton of time looking for a new set of tires (and wheels). Ive come to the conclusion that the BFGoodrich KM3's are at the top of the list. But, heres my dilemma:

1. 315/70R17
Diameter: 34.4"
Width: 12.7:
Load: E
Weight: 65.8lbs
2. 35x12.5R17
Diameter: 34.5"
Width: 12.5:
Load: E
Weight: 74.4lbs
If you put these two side by side, given those specs, they would look about the same since the are only off by a couple fractions of an inch. However, one is 8.6lbs heavier. What am i missing here? are the stats posted by TireSize.com off (https://tiresize.com/tires/BFGoodrich/Mud-Terrain-TA-KM3.htm)

For someone who wants as little of unsprung weight as possible, that weight difference seems huge.

Also, with a 17x8.5" rim with 0 offset and 4.75" backspacing, will I have to run with an additional tire carrier that moves it up and out or can this fit on the stock tail gate bracket?

Thanks...any and all input is appreciated!
Sponsored

 

WXman

Well-Known Member
Joined
Mar 1, 2017
Threads
61
Messages
2,855
Reaction score
3,076
Location
Central Kentucky
Vehicle(s)
2018 Wrangler Unlimited
Occupation
Meteorology and Transportation
What's the tread depth comparison look like? I'd believe a few lbs. but 9 lbs. does seem a little high. Interesting.
 
OP
OP
Midwest22

Midwest22

Well-Known Member
First Name
Scott
Joined
May 11, 2018
Threads
10
Messages
134
Reaction score
153
Location
So Cal
Vehicle(s)
2018 JLUR
Tread depth and everything else is all the same. I know manufacturers numbers may be off a big but 13% weight difference seems strange with such close specs.
 

Dewey

Well-Known Member
Joined
Jun 15, 2018
Threads
1
Messages
97
Reaction score
90
Location
Nor Cali
Vehicle(s)
18 JLUS
My 35x12.5 Grapplers wont fit on the stock carrier, not even close.
 
OP
OP
Midwest22

Midwest22

Well-Known Member
First Name
Scott
Joined
May 11, 2018
Threads
10
Messages
134
Reaction score
153
Location
So Cal
Vehicle(s)
2018 JLUR
My 35x12.5 Grapplers wont fit on the stock carrier, not even close.
I think it depends more on the backspacing and offset of your wheels.
 

Sponsored

OP
OP
Midwest22

Midwest22

Well-Known Member
First Name
Scott
Joined
May 11, 2018
Threads
10
Messages
134
Reaction score
153
Location
So Cal
Vehicle(s)
2018 JLUR
Looks like this may be a case of not believing everything you read. Turns out if you look at the manufacturers site you will see more realistic numbers...ones that only differ by a small amount. NOW it makes more sense!
 

Spank

Well-Known Member
Joined
Mar 29, 2017
Threads
25
Messages
2,400
Reaction score
4,022
Location
Colorado
Vehicle(s)
2018 Jeep Wrangler Unlimited Rubicon, 2020 Dodge Challenger RT Scat Pack
Remember, these are BFGs, so expect your 35s to actually measure a little under 34 when they're mounted. And with the 315s, they'll probably measure under 33. You'll always lose at least an inch with any BFG tire after you slap it on. I wouldn't even bother with the 315s.
Sponsored

 
 



Top