Allison Trans

I have W.W. Williams handle mine in Phoenix. I buy the bottle from them ($10) drain some oil into it and return it to them by mail or in person. They take it to the lab the call and email me the results in less than a week. Look for an Allison dealer repair shop near you. W W Williams sells Transynd for about $20 a gallon less than Freightliner and almost 1/2 of the price of others filters. Helpful bunch of people.