What rear end gearing do I have?
 

My truck is a 1980, came from the factory with a 350-4bbl/TH350. It's got a 12 bolt rear end, not sure if that's original though.

How would I find out what gears I have in the back?

Re: What rear end gearing do I have?
 

look in the glove box it should still have a paper tag telling you if not beats me also i think it might be on the driver door

Re: What rear end gearing do I have?
 

If it is anything but standard it will be listed in the glove box in the RPO section, if it is standard, it is most likely 3.08. There is a stamping on the axle, but I don't have the codes to decifer them...

Re: What rear end gearing do I have?
 

I have the codes for the ring gear numbers but you have to take the cover off....

Re: What rear end gearing do I have?
 

If you get in that deep you can just read them off the ring gear and divide them to get the ratio.

Re: What rear end gearing do I have?
 

I'll just look at the RPO sheet. I don't think the 12 bolt came on the truck from the factory, but I'll just assume that it did!

Re: What rear end gearing do I have?
 

from what i was told the 2500 2wd did have a 6 lug 12 bolts but i think it was in a later models not our years

Re: What rear end gearing do I have?
 

my 68 4wd has 12 bolt with 3.73's

Re: What rear end gearing do I have?
 

12bolts came factory on all 73-80's. 10bolts started showing up in 81 and 12bolts were gone by 82...

Re: What rear end gearing do I have?
 

Oh! Then I'll look at the RPO sheet tomorrow and find out! Thanks!