I did the search guys and after reading pages on gearing I can't find the solution for my situation. Anyway, I have a 2001 3.4 auto 4runner with 4.10 rear end that I just put a 2" suspension lift on and 33" tires. Now it is time to re-gear but I want to make sure that the re-gearing is still suitable for highway use going 80mph. What I want to eliminate is the constant downshifting on hills as I go down the interstate. Looking at the previous gear posts I do know that I want either 4.56 or 4.88 Can any of you guys elaborate on which would be best for my situation or what your experience has been? Thanks for the help. This site is an awsome source of info.

 

for the highway, 4.56's will almost perfectly match the stock ratio. it will be almost EXACTLY like having 4.30's on the original 265/70-16 tires.

 

You almost have to wonder though, if regearing from 4.10 to 4.56 is worth it. There really isnt that much difference between the two from a cost versus performance perspective. With my jeep, stock gears were 3.07s, and I run 4.88s with 35s, and 4.56 with 33s would be great also, however, if I had a set of axles with 4.10s, it would not be worth the cost to re-gear versus the performance. But then again, a 4runner is slightly more luxurious than my 92 Jeep

 

By no means am I one of the smart guys around here on gearing but this is my feedback. I am currently running 4.88s with my 285/75s. My RPMs now are a little higher at 75-80mph than they were when I had the stock 4.10s with 265/70s.

When I was doing my research, most of the tables told me that 4.56 would get me closer to the stock RPM numbers and performance. I went 4.88s because it gave me a little extra oomph when I was doing low speed work offroad and I was willing to accept the slight increase in RPMs at highway speeds. I am happy with the performance I have from my setup.

 

when you say 'slight', does your motor yell over 80?

 

If I remember right my RPMs at 80 mph are ~3000 RPMs. I wouldn't say they "yell" but it is noticably louder. I don't usually go faster than 75 so it doesn't bother me. The one person that I know of that does alot of driving with 4.88s and 285/75s is Jeff the Marmot. He may be able to give better info on the highway performance with this setup.

 

gotcha, thanks. hopefully he can chime in. I do LOTS of highway driving.

 

Thanks for all the replys. I think you can see the dillema I'm having. Is 4.56 that much better than what I already have? Is it good enough to justify the cost? The 4.88 are a bigger jump but would they be hard to bear on a 400 mile interstate drive at 75-80mph? Hopefully, somebody with one or the other setup can reply with what rpm they have at variable speeds.

 

regearing from 4.10 to 4.56 is a little more than a 10% increase in gearing.

that's the equivalent of going from 33's down to 30's. would that make a big difference in "feel" and performance of the truck? hell yes. you can't say that a 10% difference isn't VERY noticable.

a jump from 4.10 to 4.88 is nearly a 20% jump. when going up only 10% in tire diameter, why go up nearly 20% in gears unless you really think you're going to need the extra ummph?

 

WHAT!?!?!?

 

WHAT?!?!?! My math skills suck.......

 

match your change in gears to the change in tire size to get back to "stock feel".




4.56 - 4.10 = 0.46

0.46 / 4.10 = 0.1122 or 11.22% increase in gearing




4.88 - 4.10 = 0.78

0.78 / 4.10 = 0.1902 or 19.02% increase in gearing




33" - 30" = 3.0"

3.0" / 30" = 0.10 or 10% increase in tire size




35" - 30" = 5.0"

5.0" / 30" = 0.1667 or 16.67% increase in tire size

 

As you can tell, Andy has been part of these discussions in the past.

 

I just had 4.88s instaled on my runner with (currently) 32" SSRs. It screams 3000 rpm at 65 mph, I am hoping that a future change in tire size will correct this some what as to re-gear right now (unless cost is nill) would be out of the question. If I had to re do it all over again I would go with the 4.56 especially since you run it alot on the highway.

 

Thanks for all the help guys. I am really leaning towards 4.56 after everyone's input. I see the value of 4.88 or even 5.29 as you progressively get more serious about off-roading but I am becoming convinced that the 4.56 is a better fit for a daily driver that is still reasonably capable off-road. Now to determine how much body lift and raise funds for some lockers.

 

I personally could not suggest 4.56's. It's not like you will get less mileage with that vs. 4.88's.

I have a write-up that is a direct application for you that I would suggest you take a look at.

 

I love my 4.88's and mine runs 3400 rpm at 80, but I also have a 5spd. This is roughly 250 to 300 rpm higher than stock at that speed with 28.4" tires and 3.90 gears. I don't drive that much on the highway.

 

I guess my line of thinking is that 4.10s are pretty low gears anyways, and re-gearing will cost along the lines of $1k for parts and labor. That is a lot of money in comparison of a 10% increase. It would be different if the starting gear ratio was 3.XX, but in all reality, 4.10s are a nice gear set. 4.56 are always better, I am not disagreeing, I am just trying to justify cost versus performance. Does anyone have any gas mileage #s for 265/70s and 4.10s versus 285/75 and 4.10s versus 285/75 and 4.56? That would be a really interesting set of numbers to compare.

 

I drive a lot on the highway, and wheel probably only a few times a year. And I'd say if I could do it over again, I'd definitely go 4.56's. But then again, I jumped from 3.90's so the increase to 4.56's would be significant for me.

70 mph = 2500-2600 rpm


If you're looking for gas mileage comparison, you'll find a particular thread that was posted a while back where a bunch of us stated what our mpg was before and after a regear

 

Thanks, Ill look for it.