Just went down a size 33 to 32…..who does that

[TTU03]

I might be the first Jeep owner to downsize back to factory size tires. Changing out my worn 285/70/17 Wildpeak a/t take offs back to Willy’s factory 255/75/17. Figured with the weight I have added with steel bumpers, winch plate, winch, recovery gear and tools acquired over time it makes sense. The small quarter inch of clearance lost won’t make a difference to me. Going with Firestone destination xt. For whatever reason 255/75/17 is c rated where all other sizes of destination xt are e rated.

Adding some info in case someone ever finds comes across this looking for tire size jscan programing.

New tires are 255/75/17(factory size for willys trim), tiresize.com says they are 32.1. Tires that were on truck 285/70/17, tiresize.com says 32.8. When I changed to the larger tires I used jscan to account for the larger size.

Now I'm down sizing tires and need to reprogram for the smaller size.

Started with jscan entering measurement from ground to center cap and doubling, 30.5.
Speed odometer was 2 mph slow.
Changed jscan to 31.25 which was measurement from ground to top of tire.
Speed odometer was 1 mph slow.
Changed jscan to 32 even.
Speed odometer was even.

I used waze app on iphone. Iphone had bluetooth and wifi off and phone was not plugged into jeep usb.

Using waze as a mph check is not scientific but I dont think this has to be exact considering our tires are shrinking with every mile. It would never be dead on unless you constantly pay attention to tire changes over their lifespan.

Second check was a dotd "watch your speed" sign on side of roadway. This also matched speed odometer with the 32 inch jscan selection.

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[NC_Overland]

Oof. Personally, I just can’t stand that on stilts look. My Overland came with 255/70/18s and I switched them out almost immediately for 285/70/18s and I’ve had them since. 285s aren’t that big, but it looks more like it should have from the factory. It actually drives better in some regards. It tracks better and feels more stable. I noticed zero difference in MPG.

 

[Vincent]

I’ve ran, 35’s, 34’s, 33’s, and currently on 32’s. Sport S w/ 1.5” front pucks and 3/4” in the rear. I drive lots of miles mostly on road with only mild trails off-road, so made sense to me. Plus she’s at 207,000 miles so…. Trying not to stress her too much.

 

[TTU03]

Oof. Personally, I just can’t stand that on stilts look. My Overland came with 255/70/18s and I switched them out almost immediately for 285/70/18s and I’ve had them since. 285s aren’t that big, but it looks more like it should have from the factory. It actually drives better in some regards. It tracks better and feels more stable. I noticed zero difference in MPG.

Agree they do look a bit on the thin side. As I have gotten older I just don't seem to care much anymore about aesthetics. I mean 20 years ago the pot belly I have developed did not exist.

So far since the change I do get a sense that the jeep is rolling "easier". The 285/70/17 hit mpg by about 1 mpg, not much. When I made that change to larger tires it did seem that my automatic found 8th less than before.

Maybe its just the new rubber but these destination xt's are less noisy than the wildpeaks they are replacing. Also way less noisy then the mud tires that came from factory.

 

[JerseyMark]

Although 35s and 37s look good, there is something nice about a stock Willy’s with the 255/75/17s that looks really cool. With so many people going with bigger and bigger tires, the small pizza cutters look kind of Retro. I saw a Willys JT over this past weekend and it actually looked unique with the factory tires. Almost all of the JTs I see have 33+ size tires. The performance is probably better too with the weight savings.

 

[NC_Overland]

Although 35s and 37s look good, there is something nice about a stock Willy’s with the 255/75/17s that looks really cool. With so many people going with bigger and bigger tires, the small pizza cutters look kind of Retro. I saw a Willys JT over this past weekend and it actually looked unique with the factory tires. Almost all of the JTs I see have 33+ size tires. The performance is probably better too with the weight savings.

There’s definitely a performance difference. When I had 255s, it had quicker throttle response. Once you got moving and flat out it’s the same.

 

[Mad Mac]

The '21 Rubicon I bought in '23 had 35s on Fuel Fusion wheels.
I traded wheels and tires with the owner of a new '24 Rubicon
for his OEM 33s. No regrets.

Quicker steering, snappier acceleration and more effective braking.
The 35s felt like I was pushing big heavy tires down the road.
It was not my imagination after all.

 

[pvn.jt24]

Don’t understand why people buy trucks for MPG purposes. But meh, whatever floats your boat!

 

[MeiMei]

You will probably see better gas milage. I went from 29’s or whatever the stock size was on my wrangler to 33’s and saw a significant decline in highway milage and a slight decline in city mpg. Part of the issue was the crap gearing on stock Wranglers, but one of the very few advantages of smaller ties is they are often cheaper (almost free if you get take offs) and better milage.

 

[TTU03]

Don’t understand why people buy trucks for MPG purposes. But meh, whatever floats your boat!

I would assume none of us bought the truck for mpg reasons. I personally would like to get the best performance for my intended purpose. Occasional small load hauling, occasional use of doors/top off, occasional use off pavement, majority of life spent highway commuting.

 

[Dougstdig]

“ Just went down a size 33 to 32…..who does that”

Road and dirt road/2-track drivers that possibly tow…

 

[Blade1668]

Probably a few that do when they think about is it worth the added expense in tires vs keeping up a image or egos. My next planned tires for my Wrangler will likely be 31's same as have used most of the last 20 years on it. It's currently running 33's that I moved from my XJ. My JT will be on a set of take offs from a Wrangler Rubicon next. A slight down sizing too. Picked up the suspension tires and rims for good deal.

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