I have two 98 rams both with a 12 valve cummins. The temperature sending unit let go. they seem to be the same on both trucks . I believe its a 3/4 NPT with a single threaded stud that the wire slides onto. I have searched the web and ebay and can not find one like it . all the ones i see have 2 wire plug. Any one happen to know the part number of the unit im talking about ? thanks Mike

 

Good thing you couldn't find any aftermarket sensors, they don't last.
Go to Cummins and pay more for one of superior quality.

 

I'm assuming its the coolant temp sender your looking for? here is a list of part numbers for it that I compiled when I had to get one after breaking mine taking the head off.

• Cummins # 3920363
• Mopar # 4720314
• Napa # TS6681
• Autozone # TU276
• Advanced auto # WT426 (BWD brand) and # TU276 (Wells brand)
• Rock auto # TS382
• AC Delco # 2131116
• O'Reilly's # WT426

 

That part may work . It looks like the correct size thread. How ever the connector end is different . Mine is a round threaded stud. like a 10/32. I am sure i can just cut the wire and put a spade tip on it but I would like to find the right sending unit.

 

i just put a new temp sensor in mine over the weekend. @bjtech has the correct part #'s.