I have a 97 Ram 2500 with 5.9L cummins 5 speed manual. My problem is that when the interior of the cab gets hot every summer I have to replace the clutch position sensor. After that it will start every time until the next summer. The local diesel repair shops and dealers are as perplexed as I am. I would like to know what I can do to fix this once and for all or possibly bypass the sensor all together. Any insight is very much appreciated

 

I'm guessing grounding one of the wires in the switch may be the answer but wait a bit before you do. By chance, have you dissected one of the faulty switches to determine if it's worn out or actually failing due to heat?

 

I have taken the last one apart and seems to work fine on the bench but installed it fails under heat. A new one will last until next summer, then I have to do it again

 

Check the mount. Just a guess, but it could be the switch housing is being put under some strain when you tighten the mounting screws. New, this wouldn't be a problem but once it's been heated a bunch of times the plastic could soften and it may deform, causing the contacts to be out of alignment, thus causing the switch to fail.