40s Tires Breakdown. Which is the best?

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PorterW1111

PorterW1111

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Hey Zombiekiller,
What about running the 39 KR's which are actually 38.5" and 5.13 gears on 4wd raptor?
Why are running 5.13's, 40's and 4wd an issue?
Thanks in advance
For me I’m not the biggest fan of gear swaps. Shops around me seem to never get it right. Right now my truck is set at 4.88 I plan to run 40s and am only 2wd. So instead of bumping up to 5.13 I’m just going to add a supercharger...

From my experience you either need more power or more gears...
 

zombiekiller

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Hey Zombiekiller,
What about running the 39 KR's which are actually 38.5" and 5.13 gears on 4wd raptor?
Why are running 5.13's, 40's and 4wd an issue?
Thanks in advance

the pinion gets REALLY small when you go above 4.88s. the front differential is a RR 8.8. There is no way 5.13s will hold up. The first time that you mash the pedal with the wheel turned and one of those tires hooks up when the other doesn't? KABLAMMO.
 

MrGable27

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racer price on KR3 generally floats between 250 and 550 per tire, depending on how many you buy, who's account you're using, etc.

the Baja T/As ( KRs) are 39s and wayyyyyyy different from the KR3.

KRs feel like controlled chaos. They are very "slidey", yet very predictable. as Harry said in days of thunder, " loose is fast and on the edge of out of control".

KR3s feel a lot more hooked up. They will still slide, but don't feel as loose. I think they are more predictable than KRs, but a lot of guys that I run with prefer the controlled chaos driving feel. ( it also makes for better pics due to wheel spin ).

The KR3s are quite a bit lighter, a little skinnier, and a full 1.5" taller when compared to the KRs.

KR3s get better as they wear, KRs do not.

Yeah I’ve talked to him a few times about those tires, and he mentioned basically everything you said. They’re bomb proof but loose; which out in the desert is a good thing.
 

06z

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I went from a method cast wheel at 31 lbs and a General Grabber 37” at 81 lbs for a total of 112 pounds.
I went to a Titan7 forged wheel at 21.5 lbs and a BF Goodrich KM3 40” at 87 lbs for a total of 108.5 pounds. Very happy.
 
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PorterW1111

PorterW1111

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I went from a method cast wheel at 31 lbs and a General Grabber 37” at 81 lbs for a total of 112 pounds.
I went to a Titan7 forged wheel at 21.5 lbs and a BF Goodrich KM3 40” at 87 lbs for a total of 108.5 pounds. Very happy.
PICS!!?
 

06z

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Sorry PorterW1111,
They were installed on my truck in November. I will hopefully get my truck back from HM this week, I will try to weigh one mounted on a Titan7 wheel. I already sold the Generals a few months ago. Couldn't get rid of the Methods fast enough. I know of 2 that cracked in the last 4-8 weeks on well built mid and long travel raptors. I will personally go forged only for wheels.
 

06z

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The wheel is balanced with almost 1/2 pound of weight on it. I known that the wheel is 21.5 pounds as I weighed it before. So the tire, Apex valve stem with tpms weighs 91.2 pounds.
Total weight of the complete balanced wheel/tire is 113.2 lbs.

So, real world weight is 4.2 pounds heavier without the balancing weights. That still is awesome in my book.
 

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