oldschoolfool

Have a stock 2000 XJ SE that came with 235/75/15s and want a wider tire. Not necessarily a taller tire but a WIDER tire. No lift and don't want one. The question is how much reduction of the offset is going to cause (possibly) scrubbing on the fenders front and back of the wheels with a 255/70/15 or 275/60/15? These appear to be about the only two sizes in a 15. This is a grocery getter and not for off road and if it did see anything off road it would probably be sand.
I know I will have to push the wheels out some to keep the tires off the suspension but the question is, how far out can I go?

EZEARL

With a 255/70R15 I'd go with a 7" wide rim with 0 offset (4" b/s) or +6 offset (4.25" b/s)
With a 275/60R15 I'd go with an 8" wide rim with -19 offset (3.75" b/s)


https://tiresize.com/tiresizes/255-70R15.htm
https://tiresize.com/tiresizes/275-60R15.htm

awg

if you have a stock vehicle, scrubbing on the stock LCA is your 1st hurdle

You will gain about 1/2" by replacing them with tubular LCA

(I also fitted 2000 Ford Explorer 16" wheels, which give me another 1/2")

255/70/16 tyres, (with a 2" lift) and they still just touch the LCA

The 16" alloy wheels are also lighter, and tyres slightly cheaper

I do not wish to reduce my turning circle by screwing out the steering stops

oldschoolfool

Has anyone actually run 275/60/15s with -19 offset? It doesn't appear to be a common choice since the tire is only 28" tall. I cannot locate any pictures of 275/60/15s on a Cherokee.
My calculations come up with an 8" rim with an offset of zero works for both tire sizes. Problem with that is it limits the wheel choices. I like the white spoke look of the old Cherokee Chief days.

oldschoolfool

As long as I push the tire out a bit more than half of what I gain in width I shouldn't hit the LCA. I'm worried about scrubbing the fender flares, not the suspension/steering/brakes.

RocketMouse

also keep in mind....the wider the tire... you may increase the risk of things like hydro-planing, etc. in bad weather.

oldschoolfool

True enough, but a 255 or 275 is narrow when compared to a 33x12.50. And like everything else there's always some kind of trade-off.

RocketMouse

Well when you put it like that.... yeah... true. lol

awg

I think a 275/60 tyre on stock lift with 8" wheels would be a risky option, cant see how that wouldnt scrub on things

be very surprised if you could get away with < 1" outward movement of tyre

a 255 has the advantage that it will stay just within the stock flares, (required for inspection purposes in my State)

you should also be able to fit 255 tyres on 7" wheels if you want

EZEARL

"I think a 275/60 tyre on stock lift with 8" wheels would be a risky option, cant see how that wouldn't scrub on things."
I agree but it's only 28" tall so there's a chance it'll work. Of course then there is the issue of his suspension and its condition. How much squat has it got.

The 255's would be have a better chance of working since he's mostly on road and they're not much different than a 235. Sounds like he wants to stay with OEM rims since mentions pushing them out.

oldschoolfool

Both you guys are correct, the 275 is risky but at the same time I am no stranger to pushing the envelope in this respect. The 255 should have a better chance of fitting simply because it is narrower even though it is the taller of the two sizes.

Not correct however in that I'm not concerned with staying inside the fender flares necessarily (North Carolina gives 4 inches I believe). Nor am I necessarily inclined to stay with OEM rims either. It may work out that way, but there is no such requirement or even desire to stay with stock rims. The one part of that is that OEM rims makes it a little easier to stay hub centric vs lug centric.

8 inch rims vs 7 inch is simply my preference. All these sizes will fit on either width.

oldschoolfool

Nobody seems to know, I guess nobody has ever tried it.

I put on a 1.25" (32mm) thick spacer which effectively changes the offset from +25 to -7 on a stock wheel. The result was a good inch of clearance at the closest point the tire comes to the fender (or fender flare if you will) while turning the steering left or right. This places the outside surface of the 235 tire almost the same location as would the 255 be on a zero offset wheel. The difference is .07" to .08". Hardly more than a 1/16 inch. The diameter of the 255/70/15 is 29.1" compared to 28.9" on the 235/75/15. A couple tenths of an inch overall diameter. Zero offset will move the tire about 1/4" back closer to the vehicle than the -7 where I set it using the spacers, giving even more room. The inside surface of the 255 will sit about 1/4" further AWAY from the suspension/steering compared to the stock 215/75/15 size. No chance you would rub the LCA on a stock setup.

I'll go out on a limb and say the 255/70/15 will fit at zero offset with flying colors with no rubbing during normal use on a stock setup. Diagonal across a ditch is not normal use.
I'm inclined to say the 275/60/15 will also fit but I want to take some more measurements.

oldschoolfool

Seems it's going to take putting a 275/60/15 on to prove that it won't rub.

oldschoolfool

Put a 275/60/15 on a stock steel wheel this morning and it fits perfect on the Jeep. There is 3/4 inch clearance at the worst spot which is between the outside front corner of the tire and the plastic bumper/fender flare. Since the setup is effectively -7 offset with the spacers, a zero offset will only fit even better. This is a perfect size tire for this vehicle without it being lifted. A nice wide stance without the tire poking out too much. Some, but not too much.

oldschoolfool

At the end of the day....