Hi- I wanted to see what the benefits of re-gearing my T4R would be. I'm running a 285 and don't plan to go any larger. I'm looking for opinions of why to do it or not, as well as the benefits for doing it. Thanks-

Are you happy with the performance you have now? If you are leave it alone. If you want better acceleration, less gear hunting on hills and in general a more fun 4runner then regear it. On my Jeep Wrangler I used to have it turned into a dog when I put 33" tires on it. when I put in 4.10 gears it returned to a fun fast accelerating vehicle. Well worth the money in my opinion. It makes the vehicle feel 1000 lbs lighter and not like you are always pulling a small trailer around.

Other than cost what is the downside to regearing? Might be good for someone considering it to know the negatives. @Jeremy556 any input

Downside is:

1. Cost
2. Running at higher RPM at every speed results in
A. More engine noise
B. Less MPG on the road at highway speeds
3. You will reduce the top speed capability of the rig... because we all know that lap time is important to us!

Another positive is that city driving is slightly improved MPG (very slight) due to less work getting the rig going.

The second negative is offset depending on the size tire you run. I get better MPG with 34s than I did with 33s due to increased efficiency of gear ratio to tire diameter. There is always a point of diminishing returns and @1engineer hasn't calculated that for me (probably because I didn't ask... because I don't care)!

He is too busy shining up that new mountain bike...

Only other possible downside is installation issues. You need to find a shop that does a lot of Toyota diffs. I had good luck ECGS's rebuilt diffs with gears and lockers installed.

Thank you all for the input-

A couple of things to add to what the others said.

I don't think it would impact top speed. Several reasons. First being that you still have another gear (normally you would hit top speed in 4th gear). I'm just not 100% sure the transmission will shift to 5th at WOT. Second reason is that stock top speed in 4th (if the motor could overcome resistance) would be about 150mph. With 4.56 and 285s that would be ~130mph. So, I think it will still make top speed in 4th, but as we all know, it does not matter on these trucks as it is super sketchy to go over 100mph and pretty much pointless.

The difference in acceleration is pretty significant on these motors. It just suddenly feels quick. I should test 0-60 just for grins, but it seems to do much better.

Another big benefit that most overlook is the improved crawl speed offroad. I calculated it the other day and I think I came up with (4Lo 1st gear with 4.56) is 41.3 compared with stock (3.73) at 33.7. That is about a 23% improvement, which results in better feel and control both going up and down. This is obviously offset with larger tires than stock... but you are still getting a big benefit from this. I really like having a good crawl speed and it is one reason I'm sticking with 33s for the time being.

Like other said. The downside is mainly Cost, MPG and noise... You would also have trouble with warranty if anything went wrong, even it was a stretch, transmission....(Toyota is not cool at all about this type of stuff, they avoid warranty work like no other).

If you are going to do gears, might as well add lockers front and rear (just front if you already have rear) while at it. You are already paying/doing the labor to swap both diffs.

Going just off memory here….4.10 with 285 wheels would be about equal to stock 3.73. The reason all go with 4.56 is because that’s the only option since Nittro said they will not offer 4.10 in the foreseeable future. Now that the FJ is gone and the 4R market seems to be growing that may change at some point – may be worth a call to them for an update.

Even if you off road each and every weekend your truck will still spend 90%+ on pavement.

I don't think I would bother with 4:10. Another reason to re-gear is weight. And if you plan on any off-roading, you will be adding a significant amount of weight in armor. I think one member recently mentioned his truck was 1,600 lbs over stock.

Don't forget, gears create torque at the wheels in the form of a multiplier. You really are adding effective torque with gears. Not HP, so won't really be that much faster, but torque wins the day for drivability.

The only time I would even consider wanting a lower gear ratio (4.10 over 4.56) would be on a long trip on very flat ground or downhill.



For my daily commute or 1hr hilly drive to the offroad park... It is perfect. But I guess everyone is different.

Was not really commenting on which is better but just wanted to point out that 4.10 with larger tires would bring you back closer to stock, which I think many would find appealing.

While my truck sees less pavement than most I did not regear when I had to chance. If 4.10 was available I think I may have given it much more consideration.

gears are getting close to the top of my shopping list as well.
just to be clear, are we talking about increased noise due to higher engine rpm, or are the gears themselves louder, and if so, how much louder?

I to am interested in that question, I Would assume that if installed correctly they would not be any louder then stock and certainly not loud enough to hear over a MT/aggressive AT tire. Comments from those who have them?

I would think if you can hear them over tire noise, they aren't setup properly. I certainly can't hear them over MTRs .

Louder from higher engine RPMs.

I wish Toyota offered optional gear packages. I would have wanted 3.9 or 4.1 with stock size tires.