Wheel Size vs Articulation for rocks/jeep trails

Is more 'up travel' better than more overall tire diameter in the rocks/on jeep trails?

So in real world terms, which would you pick; 35" tires at the expense of 1/2" up travel or 32" tires with the full articulation allowed by the suspension?

And just for fun, how much extra would you pay for your preferred configuration?
Because of course your preferred way will cost extra.

 

You'll easily get 1/2" of additional sidewall flex when comparing 35s to 32s, negating your loss of up travel from the taller bump stops.

 

Pick the tires you want for the axle ground clearance that you want. Pick the springs that will allow them to fit. Cycle suspension to measure for shocks. Pick appropriate shocks and shock hoops (or coilovers or air shocks or whatever suspension you are on). Cut body if necessary. Enjoy unrestricted up-travel and an insane amount of down-travel too!

This is my leaf spring samurai on 37s w/14" travel shocks.

 

Those little Samurais can be modified into some pretty nimble machines. Their small size and light weight can be a blessing, especially if you bury it in the sand.

 

As with anything, it depends. But it's not an either/or situation, if done properly.

For rock crawling, down travel is preferred. This is so that your CG is kept as low as possible. Comp rock buggies often have their ride height essentially on/near the bump stops, so basically all their suspension travel is droop. I built an r/c rock crawler a while back that has no springs. Just front/rear 4-links with shocks. On flat ground it rides around with the shocks bottomed out, but it handles amazing in the rocks.

No one is going to notice a 1/2" of wheel travel or clearance.

Pick whatever tires you want, and set your max up travel (set your bump stops) based on tire interference with fenders, and most importantly how much cutting you're willing to do. The more cutting you do, the more you'll be able to keep that same up travel with larger tires. For 35's, if you want to maintain that "stock" ride height and up travel, you'll need to cut the crap out of the fenders. It's been done, there are guys here running 35's with essentially stock height suspension.

Then you can start thinking about how much travel you want/need, and what your ride height will be. If you rock crawl, set your height closer to the bumpstops. If you jump it or hammer it in the desert, you'll want it to sit higher for more up travel.


What most people end up doing is some sort of compromise. There is a reason that 33's with a ~2.5" lift is by far the most popular combo. The basic shape of the fenders are adequate to fit 33's (with the pinch weld mod of course) at full/near full compression, while at the same time lifting the truck to provide a good improvement in approach/departure/break-over clearance but not so much as to jack up your center of gravity.

 

Daayum!

 

Thank you for that insightful answer.

 

Good point.
This is why I ask you guys.

 

If you are doing mostly jeep trails and rocks, I’d go for the 35’s as the bigger the tire, the better it rolls over things and not in/through them.
And as said above, up travel isn’t a dealbreaker for flexy style wheeling, where it’s a game changer for high speed desert style wheeling.
That said, are you doing the actual wheeling to warrant 35’s?
Do you find your truck high centering or dragging too much over rocks?
33’s, or 295/70/17 or 285/75/17 (34’s) could be a good alternative.

 

I'd like to do 35s. Seems like it comes down to how much bashing, cutting and welding I want to do.
And I suppose I ought to consider regearing for 35s. (Or eff it- cuz I drive a stick!)

I'm scraping the skids a bunch, but no, I haven't actually gotten myself high centered.
**JINKS**
But I'm currently running stock tire size and I do have to take a lot of 'B" lines.
So IDK if that means I need 35s or that I don't, lol.

And sadly I'm not going to be desert racing anytime soon- in my truck, although my driving services are available upon request!

 

Do some searching on guys with 35s. It’s not trivial to get them to fit. People still drag their skids on 35s, so...

Keep in mind people do the Rubicon on 33s. Hell they used to do it on even smaller tires...

Even with 33s you should seriously consider re-gearing. For rock crawling, you probably want a lower than stock gearing anyway.

I’m of the opinion that if you’re going to do 35s, and especially if you want to rock crawl, you should also seriously be considering SAS. IFS can only take so much.

 

That is a lot to chew, if we're talking SAS. And not something I planned to do, tbh.
I was hoping to get away with just some spindle gusseting and such.
I am already planning on regearing at some point because I will do lockers.

Hmmmm. I suppose that is what you meant about going to 35.
It is so easy to forget it is more than just getting them to fit locked and stuffed.

The problem is, on 33s I would be compelled to pick better lines everywhere I go!

 

What armor are you running @ssd_dan? If you don't have full skids (not the thin factory splash guards), sliders, and a high clearance bumper in the rear I wouldn't waste your time and money on 35s and the necessary work to gain 1.5" of ground clearance over a 265/75/16 that'll fit without cutting.

 

I run a trilogy of proper BAMF skids and real rock sliders from Shrockworks. I need hc bumpers tho.
I just drag the back end for now- no tow hitch hanging down, so there's that. Did I mention I need bumpers?

I have no problem with cutting- err, actually I do.
But I've accepted the fact that when the time comes, sawzall blades will be drawn and metal will be rendered in the name of greater clearance.
Also since I did the lift already, I figured the big $$ part was behind me. Ha ha. Ha ha ha ha ha ha ha! LOL

 

Take what I say with a grain of salt, I'm just a guy with an opinion. I'm still running 32's, lol...

You should be doing that no matter what tires you have...

I ran the Rubicon with a friend up past little sluice and back (only had time for a quick day trip), and we drove his jeep on 35's. He let me drive on the way back and honestly it was pretty easy. Granted we didn't make it far enough to hit the real hard parts, but on the way back from little sluice, I barely had to think about lines. The 35s almost seemed like cheating, lol.

There is a reason we have this imoji:




My attempt at a "free" mod to gain more approach angle (removing the lower plastic bumper valance, and moving turn signals) resulted in ~$500 for a CBI DIY bumper, $800 for a VR10 winch, and another hundred or so in steel plate to build my skids. Add in another grand because my old welder was just maxed out trying to weld the 3/16" steel. Oh, and another $30 or so for relocating the windshield washer reservoir.

So my "free" mod cost me ~$2500.

 

Why do you have to lose 1/2” of up travel with 35s? Why not tub / trim enough to not lose any up travel?

articulation in this case is not limited by the suspension, it is limited by the firewall / fenders.

 

This is my old M38A1 Jeep rock crawler that had 33" TSL Super Swampers and a Rancho 3" lift with RS9000 shocks

I also could easily get a 1200 RTI score on a 20 deg articulation ramp

 

At least it came with the consolation prize of a new welder and bomber winch on that custom bumper, LOL.

I'm too poor to not buy a welder.
But I am also too cheap to buy a welder.
And so yes,

Oh and picking lines is actually the point of wheeling, for me!
It seemed like cheating after i got a sus lift, better tires and aired down. Now it's the new norm. But there is always a bigger feature out there.

 

Ultimately you are right- getting the most travel out of my suspension is the goal.
But for a given amount of space (and work to create that space), is there an ideal tire size?
To some extent it becomes a tradeoff between clearance and up travel, or at least that was what where my question was going.
What I am really learning is how droop and keeping a low cog plays into my question.

Those particular numbers also happen to refer to a different but parallel question of an uncomfortable nature.
I would just say it may have to do with specs on something that could start with 'B' and rhyme with ronco.
But I won't.

 

without tubbing and trimming the fenders, you can’t go much if any more than a 33” tire. Anything past that requires significant clearancing, but can definitely be made to work within the full travel of the suspension. Past that you are limited by the strength of the factory ifs components.

The ultimate question is, how much work are you willing to do to make a tire truly fit.

To answer your question, don’t sacrifice suspension travel for a tire that does not fit the truck as is.