Looks like it worked. I did an oil analysis on three allison tranmissions we run and they all came back nearly the same. The only difference was this one was run 800 hours and the others were 300. I did not change the oil in them but replaced the filter and installed a better filter/header combo. I basically installed what the allison part breakdown called for. If the oil is fine otherwise, why replace the oil if I can just filter it better?