Northern California Garage Recommendations

Hey folks,

Our KZH128 campervan with the 1KZ-TE engine has in the last few days been overheating something fierce on the drive down the Pacific Coast Highway. Coolant has to be replenished frequently, sometimes several times a day on longer drives with big hills. Engine temperature goes up to the red zone and Automatic Transmission Oil light comes on from all the heat. Of course we pull over to cool down, but it is happening more & more frequently.

We've been driving the coast for a month and a half with little trouble, but the last few days have been an overheating party.

A local garage on the coast South of Mendocino thinks that the head gasket may be the culprit but they have no Hiace experience and I would like to get someone with experience to take a look.

Any recommendations for an experienced garage North of San Francisco?