this is a problem i just cant seem to figure out.my temp gauge in my truck never worked. so first place i went was the thermostat. i replaced the the other day and thought i had it but unfortunatly i didnt.1- when i removed the old thermostat it had a small rubber gasket on top of it, and then the big doughnut rubber seal that goes against the back of the t stat and through the lifting hook. the NEW t stat looks TOTALLY different then the old one, which i was told is not a big deal. but it didnt come with that first small rubber seal. i would assume that the thermostat just sits flat in the housing with no small rubber ring, and then the doughnut goes behind it???2- would anyone reccomend RTV on the lifting hook on both sides??? this is the last thing i can think of to do. 3- does anyone have a picture of the location of the coolant temp sensor on a 12 valve?? seeing as now i have to replace that becasue apparently thats the root of my problems.

My 24v tstat just has a rubber gasket that fits atound the tstat. No upper and lower, just one that fits over the lip of the tstat. Idont know about the 12v though.

The temp sensor is the very top very back (the orange thing). http://forum.mopar1973man.com/attachment.php?attachmentid=318&d=1261361932 As for the thermostat, this might help. Seem to be all different kinds. One in mine now is for a 5.9 gasser. I used RTV on mine as well.

http-~~-//www.youtube.com/watch?v=In2r9jU_k_4

I knew there would be some young whippersnapper, puddle jumping, motorcycling guy out there that would set me straight. Hello ISX. He is your 12v man.

ISX- in your video when did the assembly of the diesel thermostat, you put that first rubber seal in there, min didnt come with that rubber seal. so i just stuck the t stat into the housing and then followed that with the doughnut seal, big end in first, then the lifting plate. do i need that first rubber seal??

--- Update to the previous post...

ive looked all over and cant even find that first rubber ring. rock auto ( my main parts source) only offers the big doughnut that goes on the back of the t stat and through the lifting hook. im going to have to tear this thing apart tomorrow and try to get it right, i just got laid off and i need my truck running ASAP.

I've never seen a direct answer for this as they all seem to be different. As far as I can tell, the seal is only there to hold the thing against the recess. I think I ditched one of the seals when I put the other thermostat in. I mean all it does is open and close so as long as you have it in the right direction, it's going to work. Some have a bypass thing which is to let the thermostat see a more accurate water temp but I have used both and couldn't see much difference. As long as you put RTV between the metal to metal pieces (lifting eye) and you put the seal in in such a way that it will hold the thermostat in there (rather than it being loose in there), and have the thermostat in the right direction, I think it would work just as well. I have used a couple different ones and they all work fine.After rereading your post, it sounds like you got the older one that I had in the video. I don't see any way to get around using that small seal since it would have that big of gap in it to play in without it. I don't know if you could turn the big seal over and have it smash against the lifting plate and tstat or if it would still have a lot of play.

Have you resolved this issue yet?I bought my 97 with a thermostat gasket leak... Turns out the headgasket was leaking directly under the t-stat. It was fun. Mine did have 2 t-stat gaskets.. The doughnut and the smaller one.

I did resolve the issue. I ended up RTV'ing the lifting eye on both sides and reinstalled. I also didnt jack hammer the 3 bolts, just took em to a good snug