ok thank you! the full size spare is better than the donut. & since the 2 sizes are so close, I can keep the spare I have in there now, for the next 6? weeks
ok thank you! the full size spare is better than the donut. & since the 2 sizes are so close, I can keep the spare I have in there now, for the next 6? weeksWell... to put things in perspective :
Would you use the Cherokee donut spare if you had one and needed a spare ?
Donut spare : 165/80/17 = 27.4''
OEM : 225/60/18 = 28.6''
Other : 235/55/18 = 28.2''
4.2% difference between OEM and donut.
1.4% difference between OEM and other.
Math looks good to me.
absolutely. handful of years ago, picked up Daughter at college, 200 miles away. got to campus & ripped a tire on a curb. yeah brilliant Dad. put on the full size spare, loaded the dorm room into the Jeep & drove 200 miles homeI went with a full size spare so I can keep on truckin' at highway speed to finish whatever highway trip I'm in the middle of
thank youWell... 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%.
hehe fun!@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.
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('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
oh ok interestingOk 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 !!
thank youNot 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...![]()