Hello,I am new to this ,but i have a 97 gmc seirra 4x4 with 373. gears and the rear end is going .i went to my local gmc dealer and i told him my vin number and he told me what my gear ratio number was .doe's any one know where i can get that info with out taking off the basket cover on the rear end .or how i can tell by reading the vin.what number to look for that would tell me that the truck would have the same ratio is to what i have .thank you in invance for any and all help.geno

There is a sticker inside your glove box with the RPO codes, you should find a GT4 on it. GT4 is the RPO code for the 373 gear ratio and any vehicle made with that gear ratio should have that code

Any time you don't know your gear ratio, an easy way to find out is to jack up the truck and turn the rear wheel one complete turn, have a buddy count the # of turns the driveshaft turns around and that is your axle ratio. Remember, if your truck is non- posi, make sure both rear wheels turn together or the differential will give you a false reading!

Check your glovebox for the build sticker.

GT4 3:73
GT5 4:10
GT7 3:33
GT8 4:10
GU2 2:73
GU4 3:08
GU5 3:23
GU6 3:42
GV2 5:83
HC4 4:56
HF8 4:88
GN9 4:11
GH0 3:54
GK9 4:63
GL3 6:17
GM1 2:59
GM3 3:45
GM8 2:56

Your Ratio should be located somewhere right of center about the second or third row down from the top and most of the time begins with a 'G'. Your truck should either be a GT4 or GT5.

-slacker