C1 or C2 Load

JMT

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Another tire thread...hope you're not tired!

So I'm just browsing Cooper tires and I notice that some are C1 load and others C2. So I try to figure this out and it's something about load capacity at max pressure. I'm not sure I really understand but which do we want for our Jeeps?

Also, can anyone comment on the Cooper Discoverer MTP? They run a little cheaper than the Discoverer STT Pro.
 
From my understanding a C1 tire is able to have a higher air pressure than a C2 tire. This doesn't affect the tires ability to carry the rated load but it will change the "feel" of the tire or the "responsiveness" of the vehicle. If you are used to using an "E" rated tire for example and like the way that it "feels" when you drive your jeep, then you would want a C1 tire as you can have a higher air pressure that makes the tire stiffer. Lower air pressure can soften the ride but also make the tire feel "squishy" if you know what I mean. My one caveat is most drivers will notice this in a heavy truck or a vehicle used for towing. But our Jeeps are so light in comparison that you probably wouldn't notice a difference between a C1 and C2 tire. To answer your question on air pressure, what size tire are you looking at? 31s which you currently have or something larger?
 
Looking at 33's...for sometime down the road...

Right now I run 26-27 psi on my 31's
 
I've run 33x9.50 BFG KO and I ran those at 30-32 psi on my old Chevy truck. From what I know about 33x12.5, is that you want to run at 25-26 psi range for the wider tires. Its going to depend on how much your jeep weighs (hard tops are heavier for example) and which tires you run. So if you upgrade to 33's you could start at 26 and adjust accordingly based on the ride.
 
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If I'm understanding how to apply this, wouldn't a C2 tire give better traction when aired down for off-road than a C1?
 
If I'm understanding how to apply this, wouldn't a C2 tire give better traction when aired down for off-road than a C1?

No, 10 psi on a C1 is the same as 10 psi on a C2. The difference is that the C1 tire will have less side bulge and feel be slightly stiffer.

My advice is to not over think this. Either a C1 tire or C2 tire will work fine for your jeep. For comfortable onroad handling, your 33s will be at 26 or so psi. When you air down, You can run either tire around 10 psi and be fine. It all depends on your trail conditions and tires (and what you feel comfortable with).
 
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What is the difference in load ratings for Jeeps?

I did some quick searching and found that E rated (Which my stock sized tires are) are stiffer/rougher than D or C rated tires?

Everyone here recommended C rated tires when I began asking questions..

..I forgot to ask for the justification.
 
The one reason I see jeepers buy an "e" load rated tire is for driving on sharp rock trails. The 10 ply tires provide a little more puncture resistance. So while c load rated tires are recommended (and what I use as well) for jeepers that spend time on the Rocks,an e load rated tire can be beneficial. Other jeepers may use a Kevlar reinforced tire with a c load rating. But Kevlar tires are very expensive.
 
I have E rated tires on my current TJ, but that's because finding a C rated tire for a 16" wheel is almost impossible. My tires are brand new and came on the vehicle, but when replaced or sold the next set will be C rated.
 
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I like the look of the MTP. I may look into those when I need tires, especially since I have been using Americas Tire for several years.
 
My winter tires are C Rating. The stock Rubi MTRs were E Rated... and my MTs are also E Rated. I got used to the ride over summer but at spring change out the difference is "jarring".

No doubt the D & E Load Ratings are tougher tires but most of us do fine on C Rated Tires.

I get new 33x10.50x15 KO2s tomorrow !!
 
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And the KO2s are on. Painted the stock wheels from my '87YJ. New 33x10.50R15s rub on the lower control arm so will adjust the bump stops, maybe look for an offset after market lower control arm. Suspension is ALL stock, no lift. But fenders are AEV HighLine with huge wheel wells.

Next job will be to narrow the 6" AEV Flare to 3".

BFG KO2s 001.jpg
 
And since I still have a 33" spare from the YJ.... even if it is 15 years old.... I figure after 40 years of driving and only 4 flats...
This will work as well as any of those "space saver" spares with an 80mile / 50mph limit.

This is the 33x9.50R15 KO. Wish they still made it. Love how tight the spare is to the tailgate.

BFG KO2s 002.jpg
 
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And since I still have a 33" spare from the YJ.... even if it is 15 years old.... I figure after 40 years of driving and only 4 flats...
This will work as well as any of those "space saver" spares with an 80mile / 50mph limit.

This is the 33x9.50R15 KO. Wish they still made it. Love how tight the spare is to the tailgate.

View attachment 18379

I really enjoyed my set of 33 x 9.5 KOs that I had on my 1967 Chevy pickup. they were a great tire size. For your spare, just make sure you check it for dry rot since its 15 years old. America's Tire won't mount a tire on a wheel that is older than 10 years old. They claim its a liability issue. Since a tire is made from an organic compound it has a shelf life (so they say). It doesn't matter whether its been hanging off the back of a jeep or stored in a garage and never used. And good idea on going back to a narrow 3" flare.
 
I really enjoyed my set of 33 x 9.5 KOs that I had on my 1967 Chevy pickup. they were a great tire size. For your spare, just make sure you check it for dry rot since its 15 years old. America's Tire won't mount a tire on a wheel that is older than 10 years old. They claim its a liability issue. Since a tire is made from an organic compound it has a shelf life (so they say). It doesn't matter whether its been hanging off the back of a jeep or stored in a garage and never used. And good idea on going back to a narrow 3" flare.
I agree.... a bit risky but no worries about mounting,,, it has been on the same rim for 15 years... lol.
 
I'll post pictures but basically using tin snips and sliding the outside piece under the inner piece. Glue, maybe rivets. With about a 2" overlap.