in my 91 landcruiser i'm going through main relays like crazy. about 2 years ago it happened for the first time, and ever since, it happens more and more frequently. it's gotten to the point that i can't drive for 45 minutes without stalling out and having to replace it. really. i'm not kidding. the toyota parts guy can't keep them in stock for me! any ideas? other than this, the truck runs fine.