The SKINNY on skinny tires

Yeah, they did an alignment and balance at the time of purchase. It was Big O, so not sure about their handy work. I’ll bring it back in. Thanks for the reply’s my dudes! Either way my tires look stellar!

 

Alright lets see some more 235/85r16s! Im about to just say screw it and order 5 KO2s. These 285/75r16s are shapoopy

 

Just got new shoes! Fyi if you are in arizona and need a set of 255/80r17s cooper st maxxs pepboys on higley and mckelips has them in stock.

 

24 hour of STMaxx (235/85R16) review as follows:

Just installed the STMaxx in 235/85R16 on a stock 2018 OR yesterday. I was torn between the STMaxx and the AT3 on account of gas mileage, the AT3 is significantly lighter. My first impressions are that 235 is a perfect fit, definitely not too narrow and good height to avoid any clearance problems. The shop installed them at 50 psi which made them wander a bit on the road, but handled well otherwise, until I drove 0.5 miles up my steep gravel road which required 4x4 (it did not with the stock wranglers). I dropped the psi to 32-35 (my tire pressure gauge isn't great) and that got the traction back close to stock, but washboard is still worse with the load range E tires.

Powerwise there was almost no notable difference, I have a manual transmission so it might be more difficult to notice. Cornering is on par, if not better, than the wranglers. The wranglers would squeal around corners constantly, these do not. The killer with these tires is gas mileage. My worst fears were realized when I did a route that would net me about 19.5 -20.5 mpg, but my console is showing 15.6 mpg. This is without correction for tire diameter but that won't get me far. Also note that I haven't run a full tank of gas through it, but things are not looking good. I am assuming it is the weight that is causing the decrease in gas mileage.

Posting this for others who are trying to decide on the STMaxx, right now I am starting to look for an escape hatch.

TLDR: STMaxx (Load E) better on the road, worse on gravel than Goodyear Wrangler Adventures. Atrocious gas mileage. Power loss negligible.

 

I have had my 255/85-16 STMaxx on for about 10k mi since my lift. I love them.

50psi seems damn high. I run mine around 36-38psi daily and 15psi when off-road.

On road and off-road dry/wet performance is fantastic.

I am an auto and I did notice acceleration is a bit slower but not bad. (I really want to go 34s/35s next set of tires so will gear)

I did see MPG drop a little but I was ready for that with lift and such a heavy tire.

All that said, I would say yes, the weight is a big factor. It is a very popular tire and if you decided to go with AT3 instead I am sure you could sell the STMaxx quickly/easily.

 

Thanks for the reply, I was just looking over the tire pressure curves on https://tirepressures.com (not sure how accurate that is) for p265/70r16 and the 235/85 and the 265 @ 30 psi has a load capacity or 2252 lbs the 235 has a capacity of 2205 lbs @ 50 psi. I'll go back to that next tank and see if that improves the gas mileage. I was prepared for a decrease of up to 2 mpg, but 4 is not worth the benefits of this tire for me, particularly given the poor gravel road performance. If that helps I'll roll back to the pressures you're running and see if I can find a happy place.

 

Remember to add the height difference when calculating MPG as well. With 235/85 at 50mi you are actually doing ~52mi. Small but does impact MPG numbers.

My first tank I freaked but when I realized I wasn't accounting for the larger diameter it brought my MPG to a more reasonable/expected number.

 

Just got these in today... LT255/85/16 S/T Maxx... Can't wait to get them mounted and get off of the OEM Wranglers...

Cooper has a $70 rebate if you buy 4... FYI.

 

Anybody near PA with a 255/85/16 with 9/32s or more tread for a spare? This size is damn near impossible to find a spare. I highly recommend buying 5 at a time for anyone looking into them

 

I would like to see this as well, is the price decent. Usually uncommon sizes go for crazy prices.

 

I pumped them up to 48 psi and did drove the usual pattern. Gas mileage is acceptable now (I averaged 19 without correction) though I threw in some less hilly terrain at the end of the drive which ticked it up 1 mpg. Of course, traction on gravel at these pressures is poor but at least I can drive the thing without dumping money out the tailpipe just for an extra 0.75 inches of clearance. I can work with this and start dropping the pressures to see if I can reduce the gravel road skiddering. I know they'd do well at lower pressures, but 16 mpg was unreasonable, for a stock truck with no armor!

Oh yeah, thanks for talking me off the ledge.

 

I’m not very good with wheels/tires/backspacing/offset etc so I figured i’d ask in this thread.
Basically I’m going to put a spindle lift on which pushes the front tires out .75” with a wheel backspacing of 4.5” or below required on a 17” wheel. In hawaii the law states your wheels can’t be past your fenders so I was wondering if i got 255/80/17s instead of 285/70/17 for example would that make it so that my wheels stay within the fender?

 

I would say your safe with both sizes, if the law is gonna give infractions on tires past fenders why wouldn't they open it up to lifted vehicles or even modified exhaust.

 

Sweet, swore 285s stuck out. In hawaii, any modified vehicle has to pass a “reconstruction safety check” to approve that it is still safe to drive on the road, and one of the biggest things they look out for is tires sticking out past the fender. Anything with a lift or modified exhaust must pass recon as well

 

I'm not saying it won't stick out with the 285s. It will be minimal. But with any modified vehicle, your always at risk once you've been pulled over.

 

Love everything about my Cooper ST MAXX 255/85R16 except the E load rating.

I have a second set of new 17” Ray10s and I’m likely going to mount 255/75R17s next week. Should be a much better ride.

And ... their Brushed Copper!

 

What’s the widest rim to wrap in 255/80? I just got some 17x8.5 Ray 10s that I was planning to use w 285s but now I’ve learned of all I have to do to fit them...

 

That is the max width for Cooper 255/80/17s. You'll probably find others in the same spec.

 

Just made the switch from 265/75/16 Wildpeaks with only 10k on them.

255/85/16 Cooper ST Maxx now