76 truck diff. to 86 Jimmy

[SNOWFREAK]

I just bought a 76' full size chevy truck for the front and rear differentials, auto Transmission and transfercase for my 86' full size Jimmy. The 76' came stock w/ the chevy 400, does anyone know what gearing is in the 76'? I have looked everywhere for it, in my Jimmy they have the gears listed right in the glove box. If I do have to pull the cover off and count the gears, which ones do I count and what do I divide it by?  

[phaon1]

There should be a code stamped on the rear axle housing somewhere.  You'll probably have to scrape off grease and dirt to find it.  Take the codes to a GM dealer and they should know what your gear ration is.

Chris

[SNOWFREAK]

Already tried that, (I should have mentioned) the people at GM were no help at all, they said well it's either a 4.11 or 3.73 I told them DUH!      geez i could guess too but that does not help me.....

[73K20]

Look for a tin metal tag located under one of the differential cover retaining bolts on the front and rear axle.  If you want to count the gears you divded the larger number by the smaller one.

1973 K20 - 350/350/205

[SNOWFREAK]

Well thanks for the info. I found it