I was reading a new products magazine that listed two heavy duty alternator companies. I believe they are direct purchase companies and are fleet providers for many government agencies. Fleet-Aid, 30421 Industrial Drive, Livonia MI, 48150, #734-425-2709, Fax-734-425-2885, email http://www.fleetaid.com. Mpi-Vital, 803 Gemini, Duncanville, TX. 75137, #800-886-8224, #972-780-0072, Fax #972-780-0160, email http://www.vitalalternator.com. I hope this can be of help to some of you heavy users that burn out lots of alternator. Mpi lists many trucks and I believe they specialize in police vehicle alternators. Ken.