I realize this post will raise questions from people that have paid too much for an Allison transmission fluid and filter service. I was nearly one of those people.
I bought my Alpine Coach in January, 2014. I've been going through the normal maintenance items to be sure things are up to snuff. I bought it from a dealer and I don't trust their claims on the maintenance.
We full-time and are currently in Grand Junction, Colorado. I saw a shop nearby called Cummins Rocky Mountain. I went there to purchase air and fuel filters for my Onan generator. While I was there I inquired about having my Allison 3000 MH serviced.
They told me a fluid change and new filters runs $499, it would be $599 if I wanted synthetic ATF. I asked if the fluid was TranSynd. They told me they use Valvoline SynGard, because the Castrol TranSynd was too expensive. I told them I needed to think it over before setting an appointment.
Back at the Junction West RV park, I told my wife about the tranmission service. She said I should walk across the street and inquire at the shop there. She said she saw trucks and motorhomes rolling in and out of there all day.
I took her advice. I walked over to Diesel Services, Inc (DSI) on the corner of H and 22 Road. I talked to the drive-in service manager, Dave.
He told me they use Allison high capacity filters and Allison - Castrol TranSynd fluid. He said the service on my motorhome with a 3000 MH and ISL engine would cost about $300!
I was obviously stunned by this estimate. He said "Look, it isn't rocket science. Four gallons of TranSynd at $42/gallon, Allison filter set @ $40, and an hour of shop time."
I let you know how it works on in Tuesday, because I said sign me up!