285/70/17 on Stock Height

As a recent transplant from the jeeping world, every discussion regarding upsizing tires also included some talk of bump stop extensions. I've noticed that it doesn't seem to be as prevalent a topic on this side of the fence (particularly for the fronts). Does the 4Runner simply have enough room to stuff 285/70/17 and/or 285/75/17 on the factory bump stops?

Yes. Plenty of room up to a 34-in tire without changing bump stops in the front. The point of interference that's always a problem on these is the body mount area at their rear edge of the front fender. On the IFS setup, the tire actually moves slightly forward as it compresses, so the interference is usually the worst at about medium ride height. Typically the rub is the worst in reverse at full steering lock. Or sometimes if you are bound up against a rock going forward. There's a decent amount of flex in the rubber bushings of both lower and upper control arms. So you'll get some movement of that tire forward and back from where it is when it's sort of unloaded or just sitting neutral.

For bump stops to have much effect, it have to be pretty limiting. And the suspension only has about 8 in of travel in the front. So I'm not sure how badly people would want to block off one or two more inches of it. Most of the aftermarket bump stops engage the arm sooner, but they compressed just as far or further than the stock ones. They soften the bump stop not to change how far the arm compresses up.

And the rear has plenty of clearance to the stock bump stops. The problem in the rear is the shock mount locations mean that for an extended travel setup, the shocks are too long to fully compress up to the bump stops - so bump stop extensions in the rear are pretty common for longer travel rear suspension setups. But it's for the shocks, not the tire hitting the fender normally.

All of that assumes something like stock offset wheels. The further out the wheel goes, the more interference you get.
 
And the rear has plenty of clearance to the stock bump stops. The problem in the rear is the shock mount locations mean that for an extended travel setup, the shocks are too long to fully compress up to the bump stops - so bump stop extensions in the rear are pretty common for longer travel rear suspension setups. But it's for the shocks, not the tire hitting the fender normally.

Thank you for the help! :thanks:

Now I've got all sorts of other questions about lifts and shock lengths, etc. but I've highjacked [MENTION=667902]5thGenHunter[/MENTION] thread enough! :sorry:
 
Thanks for all the education and insight. I ended up going with some 275/70/17 Cooper Discoverer AT3/LT E-Load tires. I already run these on my Ram 1500 and they are amazing tires (driving in snowy mountain ranges in Idaho and the tire delivered every time). I decided to not go 285 just to be on the safe side. Soon, I will be lifting about 2.5-3 inches, adding sliders, installing a 24 gallons aux fuel tank, and some skid proctection.

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