Not only that but u gotta think about what is the best material used in the chalk, best surface on the road to test it against.. (Gravel, paving bricks, asphalt, concrete etc). Visibility is also important if your eyes are on the decline...

Personally I would recommend crayola's sidewalk chalk in yellow flavor.

Or if u dare to be different, u could spray some flouroscent paint used to mark the ground.

 

Why don't you do a research write up on all the factors surrounding the chalk test? I'm sure most of forum members would appreciate it as it help us gain knowledge and security knowing our tires are at optimal performance.

 

Nah - I'll just run them at 50psi and say the hell with it

 

^

Question is; "how can a passenger car tire be rated so high compared to a larger and higher load range light truck tire? Are the passenger tire ratings just blowing smoke or are the light truck ratings vastly conservative?"

 

Since Cherokees use tires, I thought that it was a valid question ...

 

What year is your jeep? For 215/75/15 it shows 33 on my door panel.

And i do the chalk test to avoid math

 

10 ply 15" tires they still are fairly easy to find in this area. Most5 here are to young to remember the older 3/4 ton Chevy PU's with 15" split rims.......Talking about killers had a friend killed by one of them when fixing a flat in a service station.


There are a few others as well as a 10 ply tubeless I saw the other day. There are some trailer wheels 15" rated for that weight cap. also.

 

Whenever I ask about 10pr 15" they either say they can't get them or it's an expensive special order


My "old" 73 K-20 had 16" split rims and no I never saw 15" 8-hole splits (but lots of old half tons with 16" 6 hole). I liked split rims because I could fix them anywhere with hand tools and if you know what you're doing they are not dangerous. I also had a C-50 with the Firestone 20' 10 hole "widow makers" and I got along fine with them. Running on rocky gravel roads I would have several flats per season and it was just part of the routine to fix them. Also usually changed out either fronts or backs once a year. I bought used school bus tires either a front pair or four for the back every other season. It used to be quite a spectacle for the tourists until I finally rigged up a makeshift air compressor and did them at logging camp instead of the local gas station/store/cabins (they let us use their compressor and hand operated tire changer for the drop centers).


I tried to use GMT400 16" 6 hole on the square body and let me tell you that it does not work because of the backspacing (hits the tie rod end ). The old 16" 6 hole if you can find them won't fit over modern brake discs. I guess I could get them new special order from somebody like JC Whitney but they are expensive for an old 200+K mile truck.


Now I am officially off-topic


I suppose that if I did find some 15" 10ply for the Burban, I could swap off the nearly new 6plys and put them on the Cherokee ....

 

Just for y'all's information - I found the answer to the P vs LT somewhere else on the web


A P tire is lighter weight construction so dissipates heat faster and therefore is able to stand the deflection from heavier loads. An LT tire needs (and can hold) more pressure to avoid heat buildup.


BUT the P tires are subject to a mandatory 10% reduction in rated capacity when used on a pickup or SUV that may be subject to heavier loads!


So the P225/70r15 1753 lbs @ 35 psi would really only be 1578 lbs (there I go using math again). In addition, working load is 80% for all tires.


I guess one could argue whether a Cherokee is a passenger car or a light truck/SUV but considering all the crap we tend to carry I would lean towards the latter.


I also read that the chalk test is really only applicable to bias ply tires.






I really never paid attention to P tire ratings before because I have rarely owned a "car" but always half ton up through two ton trucks. The little Chevy car we have now will only take one size of tire (with the current rims) so I never read the fine print.

 

well, thank you for that information. I never knew the difference between those two. Thanks! (Not sarcasm)

 

Linkee no workee...

 

http://www.jeepfan.com/tech/checking...rect-pressure/

 

dirt method also works. Just got my grabbers installed Saturday and through the dirt method i uncovered 26psi is proper wear.