Well, several of you guys were right regarding my problem with my gauges. A number of you suggested reseating the gauges, or checking the wiring. I took a chance and went to another highly rated mechanic, who installed a ground wire and now the gauges are working well.

Emboldened by all of this, I asked his price for repairing a transmission fluid leak, and his price was far below my old mechanic who had recommended new gauges.