I have a 1980 Chevy Blazer Silverado. I was wondering if any of you guy know what gears where offered that year. I want to find out which gears it has but I don't want to pull the cover on the rear end. Or is there anyother way that i could find out. Like by the VIN or some other way.
Thanks.

 

G72 : Axle Rear, 2.14 Ratio
G74 : Heavy Duty Suspension
G75 : Axle Rear, 3.62 Ratio
G76 : Positraction Rear
G80 : Axle Positraction, Limited Slip
G81 : Positraction Rear Axle
G82 : Axle Rear, 4.56 Ratio
G84 : Axle Rear, 4.10 Ratio
G86 : Axle, Rear, Limited-slip
G87 : Ring Gear, 8.50 Inch
G89 : Ring Gear, 7.50 Inch
G91 : Special Highway Rear Axle Ratio 3.08
G92 : Axle Rear Ratio, Performance
G94 : Axle Rear, 3.31 Ratio
G95 : Axle Rear Ratio, Economy
G96 : Axle Rear, 3.55 Ratio
G97 : Axle Rear, 2.73 Ratio
Gh0 : Axle Rear, 3.54 Ratio
Gh2 : Axle Rear, 2.29 Ratio
Gh3 : Axle Rear, 2.77 Ratio
Gh4 : Axle Rear, 2.92 Ratio
Gk9 : Axle Rear, 4.63 Ratio
Gl3 : Axle Rear, 6.17 Ratio
Gm1 : Axle Rear, 2.59 Ratio
Gm3 : Axle Rear, 3.45 Ratio
Gm8 : Axle Rear, 2.56 Ratio
Gmc : Plant Code Pontiac, Mi, Usa
Gn9 : Axle Rear, 4.11 Ratio
Gq1 : Axle, Std Ratio
Gs1 : Axle Rear, 2.73 Ratio
Gs3 : Axle Rear, 3.73 Ratio
Gs4 : Axle Rear, 3.70 Ratio
Gs5 : Axle Rear, 4.11 Ratio
Gs6 : Axle Rear, 4.56 Ratio
Gt1 : Axle Rear, 2.56 Ratio
Gt2 : Axle Rear, 2.29 Ratio
Gt4 : Axle Rear, 3.73 Ratio (dup With 5 X 1)
Gt5 : Axle Rear, 4.10 Ratio (dup With Gt8)
Gt7 : Axle Rear, 3.33 Ratio
Gt8 : Axle Rear, 4.10 Ratio (dup With Gt5)
Gty : Axle, Wide Track
Gu1 : Axle Rear, 2.41 Ratio
Gu2 : Axle Rear, 2.73 Ratio
Gu4 : Axle Rear, 3.08 Ratio
Gu5 : Axle Rear, 3.23 Ratio
Gu6 : Axle Rear, 3.42 Ratio
Gv1 : Axle Rear, 2.73 Ratio
Gv2 : Axle Rear, 5.83 Ratio
Gv3 : Axle Rear, 3.08 Ratio
Gv4 : Axle Rear, 3.36 Ratio
Gv5 : Axle Rear, 3.55 Ratio
Gv7 : Axle Rear, 4.11 Ratio
Gv8 : Axle Rear, 2.72 Ratio
Gw2 : Axle Rear, 2.56 Ratio
Gw3 : Axle Rear, 2.56 Ratio
Gw4 : Axle Rear, 3.31 Ratio
Gw5 : Axle Rear, 2.73 Ratio
Gw6 : Axle Rear, 3.27 Ratio
Gw8 : Axle Rear, 4.10 Ratio
Gw9 : Axle Rear, 2.93 Ratio (dup With Gu3)
Gwl : Spring, Rr, 9000 Lbs Capacity
Gx1 : Axle Rear, 3.70 Ratio
Gx2 : Axle Rear, 3.07 Ratio
Gx3 : Ratio,transaxle Final Drive 3.33
Gy2 : Axle Rear, 3.31 Ratio
Gys : Ratio Transaxle Final Drive 3.65
H01 : Axle Rear, 3.07 Ratio
H04 : Axle Rear, 4.11 Ratio, Single Speed
H05 : Axle Rear, 3.73 Ratio
H12 : Axle Rear, 21000 Lbs, Eaton 21065s, Single Speed
Ha3 : Axle Rear, 5.29 Ratio, Single Speed
Hc4 : Axle Rear, 4.56 Ratio
Hc7 : Axle Rear, 5.13 Ratio, 7500 Lbs, Single Speed
Hc8 : Axle Rear, 3.21 Ratio, Single Speed, Truck
He3 : Axle Rear, 3.07 Ratio, 3500 Lbs, Single Speed,
Hf7 : Axle Rear, 4.56 Ratio, 10000 Lbs, Dana 70, Single
Hf8 : Axle Rear, 4.88 Ratio
Hk1 : Axle Rear, 2.87 Ratio
Hk9 : Axle Rear, 5.86 Ratio 10000 Lbs, Single Speed

 

there will be a build sticker some where on it, most are in the glove box and look for any of the info beastmode has posted it should be listed.

 

Thanks

 

jack the truck up, block the front tires, put the trans in neutral, and spin one tire, one revolution and count how many times the driveshaft spins. If its an open diff, you'll need to keep the other tire from spinning or the driveshaft won't spin at all.

 

I could not find it anywhere in the truck. you think maybe the axles are stamped with the number or code.

 

there might still be a alum tag on the axle thats bolted on the diff cover. if not you will have to do the counting as been said above.

 

Usually they got a 273, 308, or maybe a 342, thats about it that year, unless it was a 3/4 ton, but its a blazer so its not.

 

I think 308's thanks. so what size should I run with 35's 456's maybe?

 

If they are infact 3.08s and you have 30" tires now... and your only going to a 35" tires 4.56s are gonna be a bitch on the highway w/o OD, I probably wouldnt go any more than 4.11s if you like the way it rides now.

Gear and Tire calculator was

3.08s with 30" tires = 3.593333 with 35" tires