.. 8 1/4 rear end ID ? ..

Half ton truck i bet , they had 11' brakes optional with the 81/4, all the c bodies had 91/4 did they not , i had 2 newports, and 2 new yorkers in the seventies they had 91/4,s . I think the f body cop cars had 11 '' rear brakes with the 81/4 also.