rear axle ratio RPO

[BigLarryT]

I've read that there are three different types of rear ends fitted intot he 96' style s-10? what is the difference/what is the best way to find out which rear end I have? buy rear end I'm speaken of the pumpkin.

[truckinjeff]

oops

[cmorin543]

Quote: Originally Posted by the_dubster98

dont know.. i asked the same question a while back too..

GU2 = AXLE,RR 2.73 RATIO
http://www.nastyz28.com/sbchevy/rpo-eg.html#rpo-g

[the_dubster98]

thanks buddy,

[cmorin543]

I still can't figure out what the rear end on my 84 s10 2.8 4x4 is... all I see here on the build sheet is GQ1, nothing that says anything about a GU???

u guys tell me...

[BigLarryT]

I believe that this is the wrong sticker to be looking at to find the numbers ur looking for. But don't know about everyone but mine is located on the bottom side of the glove compartment. Is it possible ur sticker has been pulled or something?

[cmorin543]

that is the sticker (and the only one in the truck) that was at the bottom of the glove box... all the options match the truck, and so does the VIN #...

[baggeddraged]

heres a site with a list of all the RPO codes http://www.wiu.edu/users/muwtj1/rpocodes.htm

[UserName]

Just a bit of clarification about the "locking differential" in GM trucks:

It is dubbed "Gov Lock"

It should *not* be confused with a GM car-type "PosiTraction" unit. They are two different designs all together. A "Posi" uses clutches pushed together by an "S" shaped spring to get the friction between the clutch packs.

The truck unit is in fact a locker.

It gets it's nickname from it being developed for government-vehicle use. GM supplied many 4X4 truck to the US military, but the government mandated a locking differential be employed. To reduce costs in the long term, they colaborated with the Eaton Corp. to produce a locker with open differential characteristics, but full-on locking capabilities. It is a complicated diff unit, much more so than normal gear actuated lockers. It acts as a weak limited slip, until a predetermined amount of difference is achieved, then the unit locks by using a series of centrifugaly(SP?)-activated springs that allow levers to move into position to their coresponding vallies in the diff-thus providing full lock up.

A regular locker (Detroit Locker, EZ Locker, Lock Right, Etc.) uses torque from the driveshaft to lock the diff. What happens here is the driveshaft applies torque to the pinion, the pinion to the ring gear, and the ring gear to the carrier, carrier to the carrier pin. When this force is applied, the carrier pin "loads" the gearset of the locker, putting outward pressure on the inner gears, pushing them outwards onto the outer gears (keep in mind that this is all happening *inside* the carrier). When no force is applied, the gears will slip past one another, and the result is the characteristic "clicking" sounds you'd get while rounding a corner. This allows some differentiation of the tires, and significantly reduces tire wear (unlike the welded diff I run ).

So, in essence, some of you are right, and some of you are wrong. The term "Limited Slip" does not really apply in this case.

Now, welcome me to the boards. I'll be getting a '95 S-10 4X4 tomorrow, and I've already got a '92 GMC Jimmy -Later!

[nystateofmind27]

Great explanation UserName and welcome to the forum.

[UserName]

Glad to be here!

[Darksyde]

Quote: Originally Posted by seanchim

I want to run 18 or 20 inch wheels on my 03 ext cab 2.2. Now Im being told that I will lose horsepower because of thesize of the wheel swap, but that I can make it up by swapping the gears in the rear end. Now I know that I currently have the 4:10 now, can anyone help with what a better gear ratio would be to regain the lost horsepower?

I was wondering the same thing. I wouldn't mind swapping out rearends to get things even.

[UserName]

There is a simple calculation that you can do to figure out the correct ratio to run that will be closest to the stock setup when you swap to a larger tire. I can't seem to find it right now, but I will search around a bit and post back with the info.

[UserName]

Here you go!
Don't forget to get an ACCURATE measurement of the tires you will be using vs. an accurate measurement of your current tires. Use the "specific gear" calculator to figure out what you'll need to get (just keep trying different ratios until you get to the closest set-IE:4.27,4.56,4.88,etc.). And also remember that if you have a 5 speed that the overdrive gear is approximately "0.75", so enter that as the specific gear to get an accurate highway RPM calculation.:thumbup:



http://ringpinion.com/content/calculators/RPM.asp

[98noma]

Does anyone know what comes in a zq8 reg cab with a 4cyl 5spd

[cmorin543]

check your RPO codes in your glove box and compare it to the list at the begining of this thread - most likely they are 3.73's

[98noma]

I dont have a zq8, but I just picked up some zq8 wheels with smaller tires

[03noma]

i have a 4.10 and i want to change it what should i change it to

[cmorin543]

depends... which engine do you have?

[bww3588]

Quote: Originally Posted by mryanpilarski

How come i have a 1996 Chevy S10 with the 2.2L and i have limited slip?

I have tested it...in snow, the power shifts between wheels on the rear axle. I had my brother nail it at a stand still on ice, and the power shifted from left, to right, to left, to right, till it grabbed

thas not a locker, limited slip, or whatever the hell you want to call it. thas an open rear end. no locker. if it was a true locker or limited slip then both wheels would spin at the SAME time.

[bww3588]

Quote: Originally Posted by birdgears

4bangn, the 7.5" ring rearend you have will eventually break with 450hp v8. especially if you get on it alot. they put it in f-bodies, but it's only made to take about 300hp or so.

try to find one out of a zr2. those are 8.5 ring. not sure of the ratio, but it will bolt up. otherwise, you can put anything you want in there with enough work and/or $$'s.

sign_in_name, you are basically correct, except that limited slip transfers power to the wheel with the MOST traction, not the least. if it was otherwise, the tire with no traction would just spin 'till it gives up the ghost, and you would be stuck in that mudhole. i'm sure you knew that, and just wrote it backwards, but for those others reading, it's power to traction, not power to slippage. the best advantage of a limited slip over a full time locker is cornering. when you take a corner, the outer wheel takes more revolutions to get around the bend. you really don't need positraction (limited slip) for regular street driving, unless you tend to have a heavy foot, and spin one wheel, or you just like the look of a true burnout. one wheel burnouts dont count.

"never attribute to malice that which can be easily explained by stupidity"-anon-

click if you hate pidgeons : http://perso.wanadoo.fr/chuu/Trucs/Final_Bird.mpg

NO NO NO NO NO NO NO. there is nothing that could be more wrong about the ZR2 8.5. it WILL NOT bolt up in a 2WD. it is 8 inches wider than a 2WD rearend. even the regular 4X4's rearend it 4 inches wider than a 2WD. DO NOT DO THIS. it will only cause you time and lots of head aches when your wheels stick 4 inches out on either side. dont do it. http://www.v8s10.org/forum/viewtopic.php?t=990

[350*s-blazer]

to all that claim the factory g80 diff., is not a locking diff.(go to tthe link)
http://www.traction.eaton.com/prod2.htm
it is a auto locking diff.

[droppedforlife]

how can i tell the difference btwn a 7.5 rear end and a 7.625 rear end? if it involves crawling under the truck to measure then what you do measure? only need the info to order lsd/posi. thanks.

chris

[bww3588]

Quote: Originally Posted by droppedforlife

how can i tell the difference btwn a 7.5 rear end and a 7.625 rear end? if it involves crawling under the truck to measure then what you do measure? only need the info to order lsd/posi. thanks.

chris

1994 and newer had the 75/8 (7.625)

[droppedforlife]

Quote: Originally Posted by bww3588

1994 and newer had the 75/8 (7.625)

sweet!! thanks.

[TribalDragon]

Quote: Originally Posted by pnut420

I have a 2001 sonoma V6 with 3:42:1 with limited slip, It spins both tires on the pavement all the time, but a few times in the mud and snow only one tire was really spinning good

Okay, heres a small break down for you. A traditional limited slip, only one tire drives. When there's a torque difference both tires will kick in and run. What might be happening is when your on slippery surfaces it might think your just cornering if one tire is spinning really good and the other is spinning just a bit is it? Now I have installed An eaton "limited slip-posi" This differential acts as a posi traction (both tires drive all the time) but breaks free a lot easier and sooner if there is more torque than just a straight posi. See in lockers both are locked all the time and will not want to let go and you will most likely break an axle before it will let go, posi... will come close if you run high power and are an every day driver and take hard corners with your foot into it. Now a lot of new GM's and chevrolet if you want to label them both are using Auburn Limited slips. (which is what is in my front axle) This one acts as single drive until the tire slips a certain amount (Gm's term is actually Gov lock or whatever) but a lil centrifical clutch will catch and engage and drive both tires. Im not sure what year they started to actively use these, but I know a friend with a highrider, 01' and it has one. hope it helped

[350*s-blazer]

Quote: Originally Posted by droppedforlife

how can i tell the difference btwn a 7.5 rear end and a 7.625 rear end? if it involves crawling under the truck to measure then what you do measure? only need the info to order lsd/posi. thanks.

chris

all 4.3's came with 7 5/8 rear end with the 28 spline axles (87 and up)

[fknlow_01]

what would a mid 80's longbox auto v6 have in it for gears? i picked up the whole rear end from a friend today

[tippmann243]

how the **** should we know
it would help if we new waht motor and trans you had


check the rpo codes

[fknlow_01]

for one thing i asked a simple fockin question and you reply like that? fock you tippmann!
there was no rpo codes on the truck, longbox, 2.8, auto

[tippmann243]

take the last 8 numbers inb teh vin and call a dealer or there is suposed to be a id number on the rear

[2WD]

Can i put a G80 posi and 4.10 gears in my truck that has 3.43's before?

[2WD]

also where can i get the G80 at?

[tippmann243]

yes you can put in a g80, but if your gonna put posi in an open diff i would get something a little better thana a g80 and gears have to be installed by a pro, the tolerances have to be perfect adn if they are not, you will eat up gears

[bww3588]

Quote: Originally Posted by 2WD

Can i put a G80 posi and 4.10 gears in my truck that has 3.43's before?

i dont think you can. because the 342's have 26 spline axles and the 4.10's have 32 i beleive. but you can get an aftermarket set of gears from richmond for your 26 spline axles w/the 4.10 ratio and a posi unit from auburn or eaton for like 400 and the gears for like 200. but you would be better off to buy a 3.42 posi or somthing like that from the boneyard. but it all depends on your application. if your goin for all out racing and want good 60' times then the 4.10's would be great but if your goin for economy and mild performance then the 3.42's would be sufficient.

[2WD]

can i get the get the gears from a gm dealer?

[jtcfanof3]

I LOVE these kind of informative type threads!
Thanks guys,I had questions about my 3:42 G80 S-10 and well.........now I dont!!!
Dont get me wrong you Limited slip(or w/e you call it)guys,I love the one wheel peel,this is my first"locker".
Keep posting and I'll keep reading!
Im a newb too this code searching thing!

[2WD]

What axle does my 93 have in it?

[bww3588]

Quote: Originally Posted by 2WD

What axle does my 93 have in it?

look at the RPO codes in the glove box.

[ace]

Im wantin to put a trans brake on my 93 4.3l S10 can it be done and can my trans take the punishment

[Generic0]

I have been playing with the caculators on http://www.machperformance.com/calculators.html and im messing with the mph for rpm rance one. The truck is a 97 4.3 5spd ext cab. z85. The code in the glove box is gu4 3.08's but when i got to messing with that caculator it dosant add up. i am at 2450 rpm's at 70mph in 5th gear (.78 OD right?) That adds up to a 3.43 rear end?!!! I have the stock tire size on it. If i did have 3.08's id be going 70 mph at like 2150 rpms

I Cant make the numbers add up, what overdrive dose my trans have?

[bww3588]

Quote: Originally Posted by Generic0

I have been playing with the caculators on http://www.machperformance.com/calculators.html and im messing with the mph for rpm rance one. The truck is a 97 4.3 5spd ext cab. z85. The code in the glove box is gu4 3.08's but when i got to messing with that caculator it dosant add up. i am at 2450 rpm's at 70mph in 5th gear (.78 OD right?) That adds up to a 3.43 rear end?!!! I have the stock tire size on it. If i did have 3.08's id be going 70 mph at like 2150 rpms

I Cant make the numbers add up, what overdrive dose my trans have?

.83 OD

[Generic0]

Thanks for the overdrive # but that dident make a diffrance. im at 1500rpm in 4th gear at 35 mph. what makes peferct sence is is that i somehow got 3.43's with an open diff but with the gu4 in the glove box. If you use the caculator with 3.43's and a .83 od I turn 2460 rpm at 70 mph, My spedo is dead on. So where is the id numbers on the rear end at?

[bww3588]

Quote: Originally Posted by Generic0

Thanks for the overdrive # but that dident make a diffrance. im at 1500rpm in 4th gear at 35 mph. what makes peferct sence is is that i somehow got 3.43's with an open diff but with the gu4 in the glove box. If you use the caculator with 3.43's and a .83 od I turn 2460 rpm at 70 mph, My spedo is dead on. So where is the id numbers on the rear end at?

they are on the carrier somewhere. i think around the input shaft.

[Generic0]

so theres nothang on the outside of the case?

[bww3588]

Quote: Originally Posted by Generic0

so theres nothang on the outside of the case?

yeah its on the carrier housing. on the outside around the input shaft im sorry for that.

[Generic0]

Heres the numbers on the right side axle tube AA1 K 348 2

I have a full set of service manuals for a 99 but they dont show the AA1 paart that tells you the gears

[Generic0]

Anyone?

[Gspot]

i have an 87 s10 2.8L 5 spd 4x4 with a 3.73 posi, i've broken some of the disks in the posi and theres gettin to be a good build up of shrapnel on the magnet, so im lookin for another rear end, does anyone know if theres any problem with putting in a 83 blazer rear end?