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NFW911
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Discussion Starter · #1 ·
Its been killing me trying to find someone who has actually put 4.30 with 33" on their truck. I have a 09 6speed really want to regear cause these 33" toyos have killed my mileage not to mention whats its doin to the tranny starting to hear the effects of it too.

Ive read a few ppl got 4.56 with 33, but only have the 4 speed so dont really know what kinda mileage and rpm they are turning compared to the 6 speed

For the ppl that have 4.11 or 4.10 with 33 and a 6 speed i cant seem to find and its not for the lack of trying ive been googleing for weeks now, or havent talked about it much.

Some real things i know is alot of ppl say 4.30 and 33" is ideal, my buddy just got 4.30 but hes running 35". hes running right at 2k at 70, and averaging 13 between hw and city. im only getting 11.2.

I do mostly city driving and alot of 60, but come winter i do go from FL to MS and good bit, so i dont wanna see 10 mpg doing hw. right now i get like maybe 14 if i lucky 15.2 but ill stay in 5th most of the way.

Any help would be really appreciated, hopefully my chirstmas me and buddy will get around to doing, and id like to have a better idea of what do, cause im all kinda torn betwen 4.11, 4.30, 4.56
 

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The Canadian
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3,241 Posts
4:30 & 33's will treat you well.

final gear ratio from 6 speed to 4 speed is very, very close to the same. so cruise set @ highway speeds from 4 speed to 6 speed wont be too different.
 

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Baseball
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if you don't plan on going bigger, then 4.30 would seem to suit you well.. most go 4.56 because of future upgrades
 

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I was considering going from 3.73 to 4.10s with my 33s but i jumped to 4.88s and let me tell ya, these low gears never fail to put a smile on my face. As for you, go 4.30. Some would say go 4.56 but you got that really deep 1st gear so you're fine. 4.10 would overall be better on your gas even in the city, but you'd be happier with the 4.30s.
 

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Just go with 4.56. Don't over think it
 

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if i ever get around to it, the plan is 4.30's for my 33's. i think its the ideal gear for 50/50 city/highway driving with that size tire.

my buddy did 4.88's on his nnbs sierra 4.8 4l60 with 20x10's and 35's and he hates it on the highway. sure it moves, but if you do too much gear and like to drive over 70 on the highway, you're going to hate your mpgs. he's going to stuff some 37's to get the rpms more managable in the near future.
 

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4.10 or 4.30 will be good. I have a similar setup and if my rearend goes I will go with 4.10.. my truck gets about 15mpg highway with 3.42 and 33toyos and prolly 17ish around town (mostly 45-55 speed limit no stops hardly) 4.56 and 33s turn about 2400ish at 70 which is too much if your on the highway all the time
 

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Guess I'm not listening to my truck that well, I have factory 3.42 and am on 275/60R20 (33") and was planning on only doing 4.30 when I get around to a real lift and 37s since mathematically it only needed around 4 to equal to stock . Wish there was someone local with some crazy gears so I could get a better idea.
 

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Guess I'm not listening to my truck that well, I have factory 3.42 and am on 275/60R20 (33") and was planning on only doing 4.30 when I get around to a real lift and 37s since mathematically it only needed around 4 to equal to stock . Wish there was someone local with some crazy gears so I could get a better idea.
3/4 ton or 1/2 ton? Go 4.10 with a 3/4 ton and 4.30 with a 1/2 ton. With 33s it should turn in the 2,100 rpm area at 65mph with those configurations. The reason is the overdrive is different in the 1/2 ton and 3/4 ton.

I run 4.88s with my 33s. 2,000 rpms at 55 mph and 2,400 at 65 mph. For my use it's great cause I either drive in the city or tow long distance at just 55. Kicking down to 3rd gear is right in the torque curve for the hills.
 

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Mmm Sandwich
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Guess I'm not listening to my truck that well, I have factory 3.42 and am on 275/60R20 (33") and was planning on only doing 4.30 when I get around to a real lift and 37s since mathematically it only needed around 4 to equal to stock . Wish there was someone local with some crazy gears so I could get a better idea.
You are not considering the added weight of the larger tires just matching gear to size is not going to bring it back to exactly stock feel. Stock tires being smaller and lighter require less force to turn. So it would take a taller gear than the just the stock equivalent to get that back.
 

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I have a 13' 1/2 ton 6L80 - With a higher gear does it make the 4cyl mode more useful? Stock @ 65 is 1582 with 3.42 so it would only need 4.00 to match ratio wise. How high keeps mixed town/highway/tow in check?
On a 37 (36.8) tire:
4.30 = 1702
4.56 = 1805
4.88 = 1932
5.13 = 2031

Don't mean to threadjack but dont want to make a new thread for something thats asked a lot.
 
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