[Leems]

I could try the air down method - I have a compressor in the back now. The size difference is not small, but removing the liner may actually do the trick. These are some good ideas, thanks.

My plan of crossing my fingers may not be the best choice after all.

 

[MikeR.]

Oh yes, remove the liner. I didn't realize you still had it in there. Generally people still need to air down as well, but it might fit at full pressure.

 

[Leems]

Oh yes, remove the liner. I didn't realize you still had it in there. Generally people still need to air down as well, but it might fit at full pressure.

To be honest with you, I didn't even considered it before. I've got to take a good look at that, thanks.

 

[rumrunner]

OK, next up is another Cherokee this time w/ 17" wheels & I kept my full size spare

looking at the tire comparison charts I think I can still use the full size spare I have. diameter wise it's still a better match then the OEM temp spare, right?

car tires = 225 65 17
full size spare = 235 55 18

comparison chartrs

225/65-R17 vs 235/55-R18 Tire Comparison - Tire Size Calculator | Tacoma World

235/55-R18 tires are 0.34 inches (8.6 mm) smaller in diameter than 225/65-R17 tires and the speedometer difference is 1.2%

www.tacomaworld.com

Tire Size Comparison

Tire size comparison the easy way. Use our tire size comparison calculator to compare diameter, width, sidewall, circumference and revolutions per mile.

tiresize.com

my concern is being 200 miles away and having to drive the highway back home at 50mph w/ the temp spare, before getting a tire repaired. w/ the full size spare I can drive home at normal highway speeds

this new to me used car, will need a set of tires soon & when I do that, I can get an extra 17" wheel & tire the same size as the rest. but for now, is my full size a better spare option? if not I'll just stick it in the basement until I get Cherokee #3

any thoughts?

 

[Mark_]

Well... 8.6mm diameter difference is like a 5/32nds thread depth difference (radius measurement), close to the difference you'd have between a new tire and one at 6/32nds thread depth (new tire being at 11/32nds). It's not a significant difference. Diffference with a donut spare (165/80/17) is more like 4%.

 

[rumrunner]

Well... 8.6mm diameter difference is like a 5/32nds thread depth difference (radius measurement), close to the difference you'd have between a new tire and one at 6/32nds thread depth (new tire being at 11/32nds). It's not a significant difference. Diffference with a donut spare (165/80/17) is more like 4%.

thank you
so it's better than the temp spare

& it's ok that it's an 18" wheel? the bounce dynamics might be off? but still better than the temp spare

 

[Mark_]

thank you
so it's better than the temp spare

& it's ok that it's an 18" wheel? the bounce dynamics might be off? but still better than the temp spare

Total diameter is the main concern, wheel diamater, especially a mere 1" difference, is more an aesthetic thing.If you had a 22" wheel with a very low profile tire... then you would likely feel it on the ride .

 

[Mark_]

@rumrunner : let's get a little crazy for a second 😁

Was thinking about total diameter vs tire air pressure, and found a thread on a Forester forum where this guy did an experirment, measuring height while inflating/deflating the tires.

Anecdotally, he found that a 2 psi difference = 1/32nd change in radius (2/32nd in diameter).

So let's say you keep the spare at 40 psi, you're 4 psi over normal, and roughly 2/32nds bigger (radius). So down from 5/32nds difference at equal pressure (for your spare) to 3/32nds with 4 more psi in the spare. Things are looking up, lol.


And now don't forget you have to deal with 36 psi tires vs your Limited's 33 psi tires.

('09-'13) - 2010 - How much does change in...

We know that it is important to maintain tires with close to the same circumference on AWD cars, and pay a lot of attention to keeping identical tires with similar tread depths on the car. I have often seen it mentioned on the forum that maintaining proper tire pressures is also important as...

www.subaruforester.org

 

[rumrunner]

@rumrunner : let's get a little crazy for a second 😁

Was thinking about total diameter vs tire air pressure, and found a thread on a Forester forum where this guy did an experirment, measuring height while inflating/deflating the tires.

Anecdotally, he found that a 2 psi difference = 1/32nd change in radius (2/32nd in diameter).

So let's say you keep the spare at 40 psi, you're 4 psi over normal, and roughly 2/32nds bigger (radius). So down from 5/32nds difference at equal pressure (for your spare) to 3/32nds with 4 more psi in the spare. Things are looking up, lol.

And now don't forget you have to deal with 36 psi tires vs your Limited's 33 psi tires.

('09-'13) - 2010 - How much does change in...

We know that it is important to maintain tires with close to the same circumference on AWD cars, and pay a lot of attention to keeping identical tires with similar tread depths on the car. I have often seen it mentioned on the forum that maintaining proper tire pressures is also important as...

www.subaruforester.org

hehe fun!
lets not mix in what the current tires measure for tread, because they aren't new & the rears are more worn that the fronts (must have been rotated recently) but they are dry & will be replaced soon & I'll get 5
actually the sport doorjamb also says 33psi front & rear!. they were overinflated to 40 when I drove it off the lot & so I brought them down to 34. nice to have 4 working TPMS sensors again!

 

[Mark_]

hehe fun!
lets not mix in what the current tires measure for tread, because they aren't new & the rears are more worn that the fronts (must have been rotated recently) but they are dry & will be replaced soon & I'll get 5
actually the sport doorjamb also says 33psi front & rear!. they were overinflated to 40 when I drove it off the lot & so I brought them down to 34. nice to have 4 working TPMS sensors again!

Having wear on the 225/65s is actually good for spare matching right now, haha.

33 on the 17'' tires ? What model year is the Sport ? I didn't get the memo on that combo

 

[rumrunner]

Having wear on the 225/65s is actually good for spare matching right now, haha.
33 on the 17'' tires ? What model year is the Sport ? I didn't get the memo on that combo

2014 I'm told. I get the registration Tuesday

 

[Mark_]

2014 I'm told. I get the registration Tuesday
View attachment 223165

Ok yeah, as best I can recall, 36 psi came around for 2015+ (some trims with 17''s). 2014 was all 33 psi. Such low mileage for a 2014, wow !!

 

[rumrunner]

Ok yeah, as best I can recall, 36 psi came around for 2015+ (some trims with 17''s). 2014 was all 33 psi. Such low mileage for a 2014, wow !!

oh ok interesting
hehe I know right? it drives great, shifts great. zero indication of all the shifting complaints ppl had. heck it's shifts better than my previous 2014 ever did. I do wish the engine was cleaner & that the undercarriage was newer looking. but then, I'm greedy like that ;-)
it's got the little access doors for the headlight bulbs & I know how to replace those. don't know if it's the original battery, I hope not. it's all covered w/ a blanket so can't readily see any #s. when I went to adjust the time on the clock, the year was at 2015, whatever that means!

 

[Mark_]

oh ok interesting
hehe I know right? it drives great, shifts great. zero indication of all the shifting complaints ppl had. heck it's shifts better than my previous 2014 ever did. I do wish the engine was cleaner & that the undercarriage was newer looking. but then, I'm greedy like that ;-)
it's got the little access doors for the headlight bulbs & I know how to replace those. don't know if it's the original battery, I hope not. it's all covered w/ a blanket so can't readily see any #s. when I went to adjust the time on the clock, the year was at 2015, whatever that means!

Not sure you mentionned it (I probably missed it), but which engine in the Sport ?

Yeah the clock setting : probably a sleeper car lol. Most probable is that battery got badly discharged/died at one point and clock got a reset.

As for tire pressures : as far as I know, the jump to 36 psi in 2015 (for most 17'' tires) happened out of the blue, probably for mpg improvement. You can safely drive yours at 36 all around, if you so chose.

Battery : yep that cover is a PITA. You have 4 options I guess :
1) Remove cover and check (pain...)
2) Use scissors and open up a corner of the top cover, say near the negative post, to see part of the battery. OEM battery is easy to ID (I have pictures of my OEM battery you could look at). Don't do this near Positive post, to avoid possible shorting out with nearby metal). Then use Gorilla tape to re-seal the cover (hoping Gorilla tape sticks to that material... uhm...).
3) Use a battery tester to check status (like the Ancel BA101).
4) Let it live until it dies...

 

[rumrunner]

Not sure you mentionned it (I probably missed it), but which engine in the Sport ?

Yeah the clock setting : probably a sleeper car lol. Most probable is that battery got badly discharged/died at one point and clock got a reset.

As for tire pressures : as far as I know, the jump to 36 psi in 2015 (for most 17'' tires) happened out of the blue, probably for mpg improvement. You can safely drive yours at 36 all around, if you so chose.

Battery : yep that cover is a PITA. You have 4 options I guess :
1) Remove cover and check (pain...)
2) Use scissors and open up a corner of the top cover, say near the negative post, to see part of the battery. OEM battery is easy to ID (I have pictures of my OEM battery you could look at). Don't do this near Positive post, to avoid possible shorting out with nearby metal). Then use Gorilla tape to re-seal the cover (hoping Gorilla tape sticks to that material... uhm...).
3) Use a battery tester to check status (like the Ancel BA101).
4) Let it live until it dies...

thank you
it's got the 2.4L
yeah, I'm not throwing money at it right now except for tires soon
I'll try peaking at the battery just cuz I'm curious
gotta check other stuff tho like air filters
the bottom isn't too bad, needs a cleaning then I might brass brush the red parts & brush on some rust restorer here & there
the interior is mint. I need to amorall my all weather mats. I cleaned them but they look old on the new carpet
the tires were 35-37 today. I'm not lowering them