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4th Gen Tire and wheel Discussion of tire and wheel options

Thread: Cooper STT Pro 305/70/18 Reply to Thread
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  Topic Review (Newest First)
12-06-2019 01:31 PM
Originally Posted by str8t six View Post
you may gain a little more mpg with the AT tires, but they will still be heavier than the stock tires.
Agreed, good point. I was seasonally switching back and forth between the stock Transforce and a set of Duratracs prior to the lift and new Coopers. The Duratracs were getting slightly less MPG than the Transforce tires, probably because of the weight that you issue you mentioned. Both, however, were averaging around 17.5 - 18.0 mpg.
Also, I'm also not exactly sure how much any odometer calibration issues could be playing into the larger tires and mpg calculations. All of my numbers are from the EVIC, so there could be some marginal error in what I'm representing here because of that.
12-05-2019 10:31 PM
str8t six you may gain a little more mpg with the AT tires, but they will still be heavier than the stock tires.
12-05-2019 01:10 PM
Echetino Just a follow up...

Happy with the tires, but the MPG drop of roughly 2.5mpg was a bit of a kick to the wallet. I expected some drop off, but a full 2.5mpg was more than expected. I can also attribute some of that to the raised front-end from the Thuren 1.75" coils.

In the spring I'll get some less aggressive all-terrain tires to run during the dry season, then I'll be able to see just how much the tires impact the mpg relative to all-terrains.
10-20-2019 09:05 PM
Spazoid This is how I trimmed mine. Also cut and bent over the pinch weld and repainted.
10-20-2019 09:04 PM
str8t six mine rubbed with the stock wheels and with my -12mm offset wheels. Just have to trim some plastic.
10-20-2019 08:09 PM
Originally Posted by kylant View Post
where are the tires rubbing?
Only rubbing on the bottom of the well liner, at the bottom of the cab side of the well.
Seems to clear the radius arms.
Trimmed about 2.5” off the bottom of the liner.
I can’t seem to add pictures.
10-20-2019 08:07 PM
Originally Posted by tow mirrors in View Post
How loud are they?
Definitely louder than Duratracs, but not as bad as I feared.
They’re more aggressive than I’d realized. I’m happy with them so far, the noise isn’t a big deal to me, I like my music loud.
10-20-2019 07:44 PM
Spazoid Just did a thuren leveling kit and the coopers and I don’t have any rubbing AFTER trimming some. 20x10 -24mm offset
Coopers are 35x12.5
10-20-2019 11:31 AM
kylant where are the tires rubbing?
10-19-2019 11:20 PM
tow mirrors in How loud are they?

I did a lot of trimming but squeezed 37's x12.5 Falken at3w's with no lift. They slightly rub the control arms.
10-18-2019 04:47 PM
Cooper STT Pro 305/70/18

Just put a set of these on my stock suspension 2015 3500 CC SWB (wheels are Vision Warriors 18x8.5 +18) and they definitely rub. Seems like moreso on the driver side, which seems weird to me (why not equal rubbing?).
Anyway, I trimmed a tiny bit of the fender flair tab and that helped some, but a bit more trimming will be needed on both sides.

I should have waited until I installed a leveling kit prior to getting the wheels, but I'd read that 35x12.50x18's on stock wheels only rubbed slightly, so I figured I should be okay. I was slightly wrong...

It also appears, after further review, that the STT Pros are 35.08", not the 34.8" that my public school math calculated, so lesson learned, not a big deal, just thought I'd throw it out there for anyone else considering a similar setup.

I'll offer up a review and maybe a picture or two after I can drive it on roads that have turns...

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