Larger Tires vs. Wheel Uptravel

[Humvee4us]

For very rocky and rutty terrain, which one would be more important: 315/70R17 tires at the expense of a small loss of wheel uptravel, say 10mm per wheel and the need to use a limiter, or 285/70R17 tires but with slightly more wheel uptravel, the 10mm per wheel?

 

[Kmrtnsn]

Suspension travel between the two would be constant, the same. The limiting factor would be body/fender clearance for the tire. My Jeep has run both sizes, and can "stuff" both in the fenders. The reason I run the smaller of the two sizes now is because of my gearing, NOT clearance issues.

 

[Humvee4us]

I had assumed that he/she would be deliberately limiting travel via bumpstops to prevent tire contact with the vehicle body or chassis.

That's correct.

 

[Kmrtnsn]

For rocky terrain you'll be airing down your tires to 8-12 PSI anyway, between the two sizes I'd prefer the larger for the larger countouring contact patch against rocks.

 

[jadmt]

the bigger tire will get you over rocky terrain better and give you move ground clearance which will be at a premium when aired down.

 

[DaveInDenver]

I would personally not sacrifice travel just to fit a larger tire. One of the myths in the 4x4 world is that you always want the largest tire you can squeeze in the wheel opening but it's not that simple. A larger contact patch doesn't always translate into more traction, it ultimately depends on the tread geometry, contact area and how much weight you have on the tire.

 

[MTVR]

We just run the stock 53" tall tires on our truck, so that all 16" of independent suspension travel is available. With five lockers, I just don't think we'll need larger tires...

 

[NatersXJ6]

We just run the stock 53" tall tires on our truck, so that all 16" of independent suspension travel is available. With five lockers, I just don't think we'll need larger tires...

Have you included a service crane in your camper build yet? It won’t take long to figure out why service trucks have cranes. Hopefully, you will never have to learn why they also have inflation cages.

To the OP, I believe you were asking about a theoretical difference of about 20mm height vs 10 mm up travel. Those are virtually non-existent differences. Once you learn to drive one, it won’t matter. Someone with the other tire size won’t drive around you stuck on a trail because they chose the other tires, it will be because they are a better driver.

You can always overcome a need for 10 mm up travel by applying 5 additional mph... but when you do too many you will probably roll over... so back off just before that.

The question makes me guess that you are relatively new to this. Many of us learned to drive off road on worn out 235 or 31s on full size rigs with travel measured in fingers not inches, don’t overthink it. Run whatever is on the truck when you buy it and modify when you find your limits and still want to do more.

 

[javajoe79]

We just run the stock 53" tall tires on our truck, so that all 16" of independent suspension travel is available. With five lockers, I just don't think we'll need larger tires...

Totally relevant here. ?

 

[NatersXJ6]

Hey man he can't actually go drive the thing so talking about it in every thread is all he's got. Don't take that from him.

I’ve been there too. Spend enough time building and you never have to use something... my simple summer trailer “refresh” is starting to feel that way!