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31"s vs 33"s... What do you think?

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31"s vs 33"s... What do you think?
Kirbot

Kirbot

Jeeper
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South Jersey
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Cj7, 258 I-6, T18, D300, D30, Amc 20
I'm a long way off from needing tires, or even doing work on the suspension on my jeep, but I'd like to see what you think anyway.

31" or 33" tires?

My Jeep is going to be a daily driver, as well as being used in the woods.

My suspension will need work whichever way I go so thats not much of a factor.
The springs are sagging, and they have had leaf removed from all of them, and later on, add a leafs added.
And the shocks are to short anyway.

If I go with the 33"s I would probably do a 2.5" suspension lift and 3/4" shackle lift.
What would you suggest with 31"s?
Stock hight? 1" lift? 2.5"? Stock hight with 3/4" lift shackles?


So, what would you suggest for tires, and then suspension?
I'm sure 31"s would be better on-road, they would probably get better gas millage, and accelerate better.
But I'm sure 33"s would be much better off-road.
:dunno:
 
I think that all depends on what type of terrain you will encounter in the woods, as well as what you like the look of. In terms of practicality and nostalgia, I would go for the 31's, especially being a daily driver. Later on, if you no longer need a dailty driver, then you can move up to the 33's. That would also mean no need for a gear change, as you would notice a difference there. I vote 31's, my opinion.
 
Something else I just considered would be sticking to 30" tires like whats on it now.

It has 3 Bfg mud terrains on it. two of them are in good shape, one of them isn't so great, but good enough, and the 4th one is now just a balding highway tire off my parents van.

I really would like to step up in tire size somewhat, but if I could find 1 used 30" bfg... that would certainly be the cheapest option.

I guess I could get around on them for a while, then eventually step up to 33" like you just suggested.
 
Forgot to mention..
Trails around here are mostly sandy, some really soft sand.
No rock.
Very little sticky mud, lots of sand water, which I will probably have to avoid most of the time, my brother has learned how expensive that stuff is to play in.
The sand just gets into everything.
 
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I say pick up an extra mud terrain and wheel it for a bit and save your coins.
Then pick up some superswampers 31 or 33's aren't bad as far as price goes. However with the cost of a good lift skip the shackle stuff, just get a good suspension lift.
 
I think thats just what I'll do, I don't know why I didn't consider it before.

I'm still wondering what to do with the suspension though.
I figured I'll do the shackles because there already done it the back, but not the front for some reason.
Some people say 2.5" is just about enough for 33"s, I figured the extra 3/4" would help.

I'm just wondering what that 2.5" lift will look like with litle 30" tires.
I'll be running them for a while, and I have a fealing there going to look awfully small.

I guess I could leave the suspnsion just the way it is for now, but i'd really rather not.

It's really a collection of parts.
I think I mentioned there missing a leaf and then had an add a leaf added.
And also, I forgot, thats only three of them, the other is just a tired old yj spring.
And of course, the shocks are so short, they don't let it flex much at all.
 
check around, i am sure there are people who have removed stock, or slightly more than stock springs that they would part with. I am with Brock, get rid of the shackle lift, that would not be your friend in the sand.
 
Sand takes power and wheel speed, I'd stick with 30's or 31's as wide as you can get them for flotation. If you go to 33's you will have to regear to keep any power.
I think you should stay as low as you can for a better center of gravity if you have any sand hill's to climb.
As brock said buy a used tire for now and go out and wheel it and see what you need so you do it right the first time.
 
Pitbull makes a 31x11.50 AT and it is pretty aggressive. It would be nice and wide for sand and still a pretty normal size for the street and your gearing. These guys are giving you some good advice. I think for you 31's are the way to go.
 
CJKrawler said:
I am with Brock, get rid of the shackle lift, that would not be your friend in the sand.
Click to expand...

How do you mean?
Do they encourage spring hop or something?


Wow, just looked pitbulls up.
Look perfect for me.

But I do think I'll stick to whats on it for know.
But when I do eventually replace them, well I'll still probably go with something from treadwright since they cost 1/2 as much as anything else.

but that pitbull does look pretty nice, if it's the same as the one I saw, it's way more aggresive than what I would call an all-terrain.
 
Super swampers are usually cheap in smaller sizes. Money not an issue bfg km2's.
 
Sand causes significant strain on the suspension, and the shackle lift only gets you up in the air, it does not do anything for strength, and someone will correct me if I am wrong on this, but I think that a shackle lift will actually weaken the suspension. You can find the correct parts cheap, if you hunt the right places. The tires seem to be the most expensive thing you are looking for right now, and you could even find those used on the net if you search long enough.
 
Shackle lifts increase the leverage side to side on the spring mounts causing premature failure, but that is when your abuse of the system affects it , could be 20 years if driven on the street only.
I have used shackle lifts on CJs to avoid the stiffer springs of the next size lift, I think I am all about 2.5 inch lift and 31s on my 67, it looks right and is just balanced, easy to get into and fun. Oh that is my trail jeep
My 70 sports 33 km2s on a 2.5 lift with shacles for another 1.3/4, but it is pretty much a street queen. Only doing mild trails
 
i have 31" with a 2.5" lift. i love it. good on the road and if i see a dirt road heading into the woods i can pull off and do some trails. best of both worlds and thats what i wanted. when i get new tires im either going to stick with 31"s or maybe 32".



when i got the jeep my brother inlaw had these huge ugly shackles on it. it drove like :censored: with them

 
Kirbot said:
How do you mean?
Do they encourage spring hop or something?
Click to expand...


Think of it this way. If you make the front shackle longer then you have more opportunity for the eye part of the spring to sway side to side due to the increased leverage of the shackle. Now I am only talking a few millimeters of sway but at speed it equates to alot of wander and the need to counter steer all the time. Also take into account that your front axles knuckles has a 5 degree rearward camber tilt and when you lengthen the shackle that 5 degrees becomes smaller (maybe 4 or less). This slightly reduces the self centering effect of the steering which further causes wandering. I have a shackle set that has the stock length and then one inch lift holes in them so I can go either direction quickly. When I put them on the lift it really hurts my street drivability even though it helps slightly with articulation. For the street I keep them stock length.

I hope my explaination helps. I know sometimes it makes sense to me but other people are like WTF is he talking about. :confused:
 
Yeah I think I follow you.
I guess the shackle lift should be avoided.


I think I will stick to 31" tires, after the 30" I have need to be replaced.

Now I'm wondering about lift.
Is there any advantage to going with the 2.5" lift over, say a 1"?
Aside from looks, would there be any other reason.
I'm just afraid before I get the 31"s, my 30" tires are going to look awfully piddley under 2.5" of lift.
 
If your gonna lift it go with what you plan to use. No reason to lift it twice.
If the 30's fit now run it as is then buy the new tires and lift at your leisure.
 
Yeah, thats a possibility, it's just that the shock absorbers are so short that they don't alow much of any wheel travel.

Hmm, If I were to get longer shocks now, and do a 2.5" lift later, would I be able to use the same shocks?
 
Kirbot, you need shacks for the lift,, much damage is done wit to long or to short of shocks
CJs look great with 2inches of lift and 31s, they need 4 inches to clear 33s properly. Do not forget bump stops, they need to be tuned to your tires.

You need a bit if space under there for articulation, nothing screams mall crawler more than a fenderwell filled with tire and no room for articulation.

But then, hey you may like the mall crawler look and do all your flexin on 4 inch curbs.:eek:
 
It's under construction man. Just lift it now and get the meats later when you can.
 
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