cruisinfanatic

can someone ID this differential? The codes in my glove box and door are from another vehicle so I can't find out that way.
Truck is 98 S10, 2 wd, 4cyl auto, short bed

Gramps43

Well it would be pretty hard to ID from a picture of a rusty differential, you're going to have to do it the old fashion way. Jack the rear of the truck up and put it on stands, chock the front wheels and put truck in neutral. Then shinny under there with a piece of chalk, mark a 2 in. line down the center of the drive shaft at the U joint and a line at the bottom middle of the tire, either side it don't matter. Now twist the drive shaft clockwise, with relation to the diff., and count the number of times the mark on the shaft goes by for the tire making one revolution. In my case it would be no quite 3.5 turns as mine is 3.43. Now turn sideways and put your feet against the tire and try to turn the other tire in the normal direction of travel. If it turns with your feet holding the other tire still you have an open rear end.

cruisinfanatic

thanks,
thought you could tell by the shape

Gramps43

Fraid not, the housing, unless the whole rear end has been swapped, is the same on all of them. It's just the innards that change, too bad the RPO codes aren't the correct ones. I damn near dropped my teeth when I saw a G80 on the list in mine, wowee a posi with a 3.43 gear set, boogie time.

cruisinfanatic

I've got a shout out to a Chevy Tech. Maybe I can find out from the vin

Gramps43

He should be able to dig deeper than other mere mortals into the bowels of the GM system and retract the necessary data. 8<))))

joeytommyhawk

what do codes in glove box stand for?

tech2

do you know the vin for the chassis? here are the possibilities for a s10
<dt>GT4 Rear Axle: 3.73 Ratio</dt>

<dt>GT5 Rear Axle: 4.10 Ratio</dt>

<dt>GU4 Rear Axle: 3.08 Ratio</dt>

<dt>GU6 Rear Axle: 3.42 Ratio</dt>

Gramps43

The RPO codes represent what the vehicle was ordered with, for instance these are some of the codes for my "94". When I saw the "G" codes I was all smiles.


My RPO codes


#: 12H : TRIM COMBINATION CLOTH GRAPHITE (H) (92)


19U : PRIMARY COLOR, EXTERIOR, LAMP BLACK (91)
1SC : OPTION PACKAGE 03


1SZ : DISCOUNT OPTION PACKAGE


A:A28 : WINDOW, RR, FULL WIDTH, SLIDING


A78 : ADJUSTER FRT, ST BK, MAN, PASS & DRIVER, RECLINING


AM6 : SEAT, FRT SPLIT, 3 PASS, CTR ARM REST


B:B30 : COVERING, FLOOR CARPET


B32 : COVERING, FRT FLOOR MATS AUX


C:C5D : GVW RATING, 4600 LBS


C60 : HVAC SYSTEM, AIR CONDITIONER FRT MAN CONTROLS


G:G80 : AXLE POSITRACTION, LIMITED SLIP


GU6 : AXLE REAR, 3.42 RATIO


J: JM3 : BOOSTER, BRAKE, 240MM TANDEM, HIGH FLOW


L: L35 : ENGINE, GAS, 6 CYL, 4.3L, CPI, V6, 90 DEG


M:M30 : TRANSMISSION, AUTO 4 SPD, HMD, 4L60E, ELECTRONIC

tech2

Pull the cover and count the pinion/ crown teeth