Counting Gears
 

No tags on the diffs, and I wouldn't believe them if they were there. I jacked up the left rear and got just a few degrees more than 2 rotations of the driveshaft for each rotation of the tire. That means I have 4.10s, right? Truck is a dog. I've read on here that 4.56s are recommended for 33s. Does that get it back to more or less stock? From 4.10 to 4.56 isn't a big difference.

4 nuts, 1 brake line on each axle and 10 or so nuts on the third, 45 minutes worth of work pop the third and count them for real. Judging 'a few degrees' is very subjective when turning a tire.
a tired 3.0 is a dog to begin with. auto or stick?
4.88's with 33's...it may not seem like a big difference numerically from 4.10 to 4.56 but a lot of people's butt dynos feel otherwise. but yes 4.88's would help get it back to stock

Stick. Not too tired. I'm working on the engine. It's better than it was. Subjective, yes, but by a few degrees I mean just a few. For 4.56 it would be 90 degrees past two turns, right? So, anyhow, do I have the right idea for figuring the ratio? I'm with you on the whole 45 minutes of work to count teeth, but if my counting is correct I'm gonna say I have 4.10s. What gear ratio is going to put the RPMs vs actual speed back to what it should be? Anyone know what 4.10 vs 4.56 feels like? I don't know if 4.10s were available stock on my truck. Did PO change them to 4.10 after lifting and putting on the tires? Why wouldn't he have gone lower? I found a good site for checking gear ratios vs. tire size but I have to plug in the transmission and transfer case info. It's dark out and I just got out of the shower so that's gonna have to wait.

My experience
4.10 and 31s = Normal and still lacks power on hills

4.10 and 33s = On the flat it feels like 31s you notice less torque on hills and from a stop in 1st gear.

5.29 and 31s = Lots of torque, great for hills. Shifting pattern is very short and it runs 3400rpm going 65 in 5th gear which is a little high. Gas mileage is about the same on the flat and better in mountains. Your speedometer will be out about 13mph @ 65.

5.29 and 33s = Good torque for normal driving. Shift patter is a little bit longer and the rps are not as high as the 31s. It is a good mix of torque and rpm.

5.29 and 37s = Feels like 4.10 and 31s. The speedometer is a little off as it is still geared lower than 4.10 and 31s, but the 37s take more torque to turn.

Basically the higher the gear the number the more torque you will have, but it will lower your max rpm.
4.56 gears are common and with 33s should feel like 4.10 and 31s, this is a common swap because you buy and change the whole differential you don't change the gears.
4.88 and 33s will be geared lower than 4.10 and 31s. This generally considered the best gear for 33s but generally requires changing the gears which costs money.

If you change the gears I would go with 5.29 and 33s that way when you go to 35s-37s you are already geared for it.

Speed calculator http://www.marlincrawler.com/java/getspd_calc.html
In the calculator subtract 1" for tires and it should be about accurate. If you want it very accurate measure from the center of the tire to the ground and multiply by 2.
Differential and transmission info, you will find transmission gears here. http://www.4crawler.com/4x4/4R_TechI...#Differentials

That's good stuff. A little dumbed down, but I suppose you're being thorough, so I'll just say thanks for the details. Don't think I'll be going bigger than 33 (I'm not as big into tire size as I am articulation and armor), but I'm not shy about spending the right money for the right results. The truck will see hills, and I'm not a speed demon on the highway. I think I'll go 5.29.

you dont really need to pull the 3rd. You can count revolutions. It doesnt have to be exact, cause your chioces are 4.10 4.56 and 4.88. So its easy to tell the difference. Rotate the wheel one time and count how many times the pinion flange rotates.

To go back to stock its simple math. your speedo gear is set up for the stock tire. (see inside drivers door) Lets say the stock tire is 31" tall, and you go to 33. Thats a 6% change. Now you can recover that difference in the gears. 4.10 to 4.56 is a change of 10%. That may be just right. But honestly in my experiance 4.56 is a waste. Start at 4.88. Go 5.29 if you think you will go bigger (and if you think you will stick with the 3.0). I had 4.88 stock with 35's and the 3.0 it was ok at best. then went to 5.29's and 36's/37's and it was about the same as 4.88/35's. Then I swapped to a 3.4 and went back to 4.88's on 37's and it is GREAT (my 4runner weighs 5k+)

I did this recently to figure out what i had in the rear. you must have one wheel on the floor. then rotate the tire 20 times and have a buddy count the revolutions on the pinion. http://www.youtube.com/watch?v=i_Enyf67KTs this video shows how to do it with a locked rear 1/2 the turns of an open rear. do the math and its easy. remember locked rear 10 open 20 and count... hope this helps

You have a tag on your door panel that lists the gearing
G144 = 4.88s
G254 = 4.56s
G294 = 4.10s

You can also pull the shaft off the rear flange and look at the color code painted on the pinion.

Code:
Ratio Ring/Pinion Color Crawl:Ratio
3.42 ...42/12... Purple ...31:1
3.90 ...39/10... Red... ...36:1
4.10 ...41/10... Pink.. ...37:1
4.11 ...37/09... Orange ...37:1
4.30 ...43/10... Blue.. ...39:1
4.37 ...35/08... Green. ...40:1
4.56 ...41/09... Yellow ...41:1
4.88 ...39/08... White. ...44:1
5.29 ...37/07... None.. ...48:1
5.71 ...40/07... None.. ...51:1

This is standard for any 79-95 trucks and 4runners.

I tried that on my truck but i found out that the po regeared with a 273 gear not on the service tags. so my first gear is like 2nd. so yes if you know the vehicle history the door panel tag is the way to go.

2.73 was never offered either from the factory or aftermarket on a Toyota 8" axle. Was it on a different vehicle?

???

lol my memory fails me..I did the math but i lost the paper, i think it was either a 27something or mabey 3.23's but either way its way off nowhere near 4.10's to say the least.. i discoverd this because when in 4wd the front wheels were fighting the rears. the fronts are geared differently from the rear. im assuming the po didnt want 4wd and geard the rear with a highway gear. <--wtf? Strange i know. well i left it at that and decided to regear with 4.88's (im running 33's bfg's mud km) so im on the hunt for gears also.

These links should get you started. I am sure you could find it cheaper if you look around.
Setup Kit http://www.marlincrawler.com/differe...ilux-setup-kit
Ring and Pinion http://www.marlincrawler.com/differe...inion/rp-hilux
Solid Pinion Spacerhttp://www.marlincrawler.com/differential/parts/solid-pinion-spacer-kit
I would recommend having them professionally set up.
You may also consider a locker for the rear differential if you drive offroad.
http://www.marlincrawler.com/differential/locker

Yep, doing 10 or 20 tire revs is a good way to check:. Makes the difference 10 times larger, so instead of trying to count 0.1 drive shaft revs, you have whole revolutions:
- http://www.4crawler.com/4x4/4R_TechI...oDetermination