2004 allison

[Schwinn68]

have you changed the fuel filter lately? Do you run a tuner that adds more horsepower? what's happened is, the trans has gone into "limp mode". It will only go into park reverse and third gear. If you have a tuner you can check the trouble codes to see what it is and even reset the code. If not, I believe you can just cycle thought the ignition sequence three times without starting the truck and it will reset the code.

Should you need a rebuild, you have one of the best allison guys in the country right in California. Mike Lovrich at Inglewood transmission can set you up with everything you need. Figure on about 2200 for parts plus the install.