Cliffs: Wanting ARB lockers, might as well re-gear to 4.30. Need feedback on real world behavior with 285/70R17 if ANYONE is running this set up.

We are set to drive the 4Runner from Pennsylvania to western Wyoming/eastern Idaho this September. Chance of snow is likely in the mountains.

ARB’s would be an insurance policy if we get stuck way out off the beaten path in inclement weather. Might not need them, but would rather have them and not, rather than not have them and need them.

My conundrum is highway travels. Speeds range from 70-80 mph for long stretches of time. 4.30 would be like running 4.10’s stock.

With the rather insignificant tire size increase I don’t really “need” to re-gear, but it seems silly not to have the 3rd members built better. Plus it would account for any future tire increases (I don’t want 35’s, but 33’s MAY be a possibility).

So does anyone have experience with this gear ratio and tire size?

Thanks!

285/70 R17s with 4.30 gears is basically a wash compared to 265/70 R16s and 4.10 gears

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I’m not running 4.10’s...I have 3.73’s.

4.30’s would actually be a bit deeper than stock gearing.

4.30 is stock gearing in a factory e-locker 3rd Gen 4runner which came with 265/70 R16 tires

There is only around a 100 RPM difference at 65 MPH between the larger 285/70 R17 (31.6") tire with 4.3 gears vs the 265/70 R16 (30.6") tire with 4.1 gears

If you are going to 33" tires, you could go up to 4.56 gears and you would only be about 100 RPM higher at 65 MPH than either of the combos above.

Personally, I would not be happy with 3.73 gears and would re-gear to the highest ratio I could to meet my overall goals, especially if considering the expense and capabilities of dual locked; for me that would be 4.88 and 33s

Really depends what your overall goals are

My concern is highway travel, since often times I will spend 28-32 hours non-stop on the interstate. My crawl is a non-issue.

This is what I’m lookong at for highway speeds of 65 mph, 70 mph, and 80 mph.

Stock 3.73 w/30.61 tires:
65: 2025 RPM
70: 2180 RPM
80: 2492 RPM

These are in OD (5th gear) ideally crusing on flat ground (midwest USA).

Modified 4.30 w/32.71 tires:
65: 2184
70: 2352
80: 2688

OD as well.

So I’ve never driven a stock 4Runner with 3.91 gears, but 3.91 in a factory set up are much closer to the 4.30’s with almost 33” tall tires. I basically just don’t want to be drinking massive amounts of gasoline in this thing. It never got great gas mileage, but it would suck having to constantly stop to re-fuel.

I think I’m going to pull the trigger on the 4.30’s, but instead of the ARB front and rear, I’ll do a Detroit True Trac in the rear and then add a selectable locker up front.

Noble effort but there are some constants about our vehicles that affect MPG more than tires and gears; weight and mass.

The 3rd gen is essentially a 4000# brick on the highway. It is not aerodynamic. The more weight we carry and the taller we make it the more we brick it; and the worse MPG we get.

That being said, I've gotten as high as 24 MPG on long trips (21-22 average) in the 2WD in my sig, and it's not unreasonable to cruise at 3k rpm with the 5VZ-FE motor doing 80+ mph.

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