FIguring Out Gearing

[Obi..]

Most, if not all you wanna know:

http://gearinstalls.com/index.htm

http://www.4crawler.com/4x4/4R_TechInfo.shtml

http://home.4x4wire.com/erik/diffs/


Calculating the new Ratio:

~ New Tire Size x Old Gear Ratio
New Gear Ratio = ―――――――――――――――――
~ Old Tire Size


Yellow=High Gas Mileage, poor Torque/Power
Black=Ideal/most Factory Spec
Blue=High Torque/Power/Towing , Decreased Gas Mileage
http://www.superlift.com/images/misc/gear-chart.gif

[elripster]

Those look like good 5 speed numbers. If one was to attempt to compensate for the auto's OD, you could multiply your final result by (.85/.71) or 1.197. 33's would then be 4.88*1.197 or 5.84 where 5.71 is the nearest match.

Frank

[4runnerchevy]

This info should be on a sticky somewhere!

[04 Rocko Taco]

Stickied.

[4runnerchevy]

Your quick man.

[EWAYota]

That just makes me debate 4.88's or 5.29's even more if I were to go with 35's. Stock or more power/decreased mpg.

[04 Rocko Taco]

Your quick man.


I try. :tongueout:

[4runnerchevy]

Sounds like a winning setup. I put 4.88's in when I had 33's and a 22RE, big increase in power. I put a Supra motor and went to 36's, I knew I needed gears, I just powered through. I put the 4.3 in and I still hit the O.D. not a prob. I will be going to 5.29's and maybe different axles. I don't trust 5.71's without a bigger ring gear.

[elripster]

You know 5.29's and 5.71's have the same pinion right? That's what usually breaks.

Frank

[slosurfer]

I don't trust 5.71's without a bigger ring gear.


See this article:

http://gearinstalls.com/410suck.htm

[4runnerchevy]

Thanks Four Runner for keeping the thread on track. :headscratch:

[yotastan]

Those look like good 5 speed numbers. If one was to attempt to compensate for the auto's OD, you could multiply your final result by (.85/.71) or 1.197. 33's would then be 4.88*1.197 or 5.84 where 5.71 is the nearest match.

Frank



Hold on guys the newbie is lost here. So the auto has a lower or high gear set up the the standard?

sorry guys cant keep up just starting to learn more things

cheers

[slosurfer]

The auto has a lower gear setup (higher numbers) than the 5spd manual.

[slosurfer]

Thanks slosurfer for chiming in...I was out of town, visited w/ Corax, and as he'll back-up, there's places out there that're "off the grid", so I had no way to reply. :)

Thanks Again!

**As in a manual 5 speed will have 4.88's while the auto wil have 5.29's or 5.71's for 33's.


There, I fixed it for ya. :D

[anthony1]

Based on that chart, Toyota stock 31" 4.56 is already in the blue...
To keep in the same ratio, I guess we need 36" for 5.29 gear then....
However, I don't feel a lot of power or torque already with 35" and 5.29.

I'm waiting for my 3.slow to 3.dead before I put in 3.4.

[Obi..]

*


I'm waiting for my 3.slow to 3.dead before I put in 3.4.



*You'll want the lower gears with the 3.4 anyhow.

For example, 3.0 w/ 31 to 31's = 4.56 and 33's is 4.88..

A 3.4 mated to an R150 w/ 33's will be rock solid w/ 4.56's.

Just pick up the appropriate speedometer output piece with the appropriate sized cog and you'll speedo will work fine..

Like how when I went and did my Auto to 5-Speed swap I pulled a 31t output from a newer R150 Tacoma to claculate out my speed right without a need for a correction device.

[anthony1]

So when I put in 3.4, I have to regear to 4:88 for 35's? hmmm. Wife is not gonna like that..:)

[Obi..]

So when I put in 3.4, I have to regear to 4:88 for 35's? hmmm. Wife is not gonna like that..:)



No, no, no..what you're saying is you're throwing in a 3.4 and 35's and keeping the gears so you can tell the wife you didn't waste the money on them? The 3.4 will give just the oomph you'll want for that setup. :D

[anthony1]

The problem is I already have the 35's and 5.29....SAS, 4.1, blah blah blah....

[Argohof]

Ummm... sorry if this is a GIRLY question, but since I AM...:P
I just bought an 88 4Runner, V6/auto for my stepdaughter, and her know-it-all brother is already giving her guff, complaining that it's not shifting properly, it has a tach (yea!) so is there a general guideline as to when it should shift?
THX and sorry if I'm posting in the wrong spot...

[DHC6twinotter]

Ummm... sorry if this is a GIRLY question, but since I AM...:P
I just bought an 88 4Runner, V6/auto for my stepdaughter, and her know-it-all brother is already giving her guff, complaining that it's not shifting properly, it has a tach (yea!) so is there a general guideline as to when it should shift?
THX and sorry if I'm posting in the wrong spot...


Welcome to the forum! Do you know what the issues are with the tranny?

The A340 transmissions don't shift into OD when the engine is cold. For some reason they were designed this way, and I guess it's supposed to help the engine warm up quicker.

There isn't really any set RPM for the tranny to shift at. It uses various sensor inputs to determine when to shift (throttle position sensor, speed sensors, coolant temp sensor iirc, and probably a few others). The shift points would vary depending on driving style.

But, just for comparison, my undergeared V6/auto tends to shift into each gear around 2500-3000rpms with my driving style and ECT on. Maybe a bit lower when going into OD. If I'm driving slower around my neighborhood, my shift points may only be around the 2000 mark, maybe lower.

Also, having the ECT on changes the shift points and makes driving the 3.0 a bit more tolerable. :D

Just my $.02

[Obi..]

^Yep. During warm up it'll bog down to make the transmission and engine work harder to bring it all up to operating temps faster..that's a good thing.

As for shift point scheduling, yes, 2500-3000 on that year w/ the ECT button in the on position, sometimes even as high as 3500. With the ECT off it can go from 2000-2750. The ECT will also cost you a couple of miles in mpg.

There's an assortment of modifications available for that setup, but in my opinion and experience after having sank a ton of play money into it all, none can replace just living with it (providing all is well in the transmission and engine) or just doing a 5 speed conversion or 3.4l/Auto or 5 speed swap..then again the money you'd spend there can afford a used 96+ 4Runner or truck with the 3.4 and auto already in it. (My 5 speed swap I won't disclose what I paid, but it is worth about $8,000 with parts and hop-ups before you even factor in the vehicle and other stuff I've done to it, and it still looks near stock.)

*Offer the 4Runner to your Son if he gives an equivalent or slightly more valuable vehicle b/c honestly he likely wants it for himself..boys are like that. :D