Its interesting. The poll shows MORE people running the 203* than the 195*. I have to say, I did not expect that.

 

I'm running both. One in my Excursion and one in my F250, but that's only because I've been lazy and haven't pulled the 203 from my Ex yet and replaced it with the new stocker I bought last year.

Stewart

 

There's lots of smart people on FTE.

But honestly, the 203* has been offered for the superduties for probably close to 10 years and I can't recall hearing anything negative about it until the last year and a half or so with the "excessive oil temperatures" claims that all originated at a single source as far as I know.

The 203* used to be a recommended mod as commonly and enthusiastically as the 6637 filter.

 

This may be of more value to those living in the colder norther climate's
If my truck warms up quicker that would be a blessing for about 8 months of the year.

Kyle

 

I don't know how far back the Dieselstop archives go, but there was an OEM cooling engineer that went by the name Auto Jim (like Mark K. is to transmissions) and he discussed the 203 t-stat at length and I believe his conclusion was the 203 held no advantages and could be slightly detrimental under the right set of circumstances. Maybe somebody can link to some of those discussions. I quit running the 203 because it does not have the updated o-ring seal that finally eliminated my leak.

 

btw- I noticed no difference going to the 203 stat or going back to the 195. The updated seal in the stocker was a problem solver for me though.

 

I have a 205* mishimoto TStat but haven't put it in yet supposedly has a lifetime warranty wich really isn't that big of a deal just never got around to installing it. Haven't seen much for reviews on them though.

 

I love my 203 in the cool months but in the summer I'm not so sure. My EOTs kinda worry me. Who sells the best quality 195? Thinking about going back.

 

Ford OEM.

Motorcraft Thermostat 96-03 - Riffraff Diesel Performance

Stewart

 

I got the 195 from Clay and installed it today. Took a 40 mile freeway run outside temps at 104. My ECT stayed at 195 on the highway and when back in town dropped to 190. My EOT ran 208 on the highway and 200 in town, a full 10 degrees cooler than with the 203. No real change on the TFT, 192-195 running the Derale 1/2" stat.

Will have to see how it does in the winter.

 

heres a question, i removed my thermostat to put the new riff raff oem one in with the billet housing, and it seems the one i removed had a cork gasket and a rubber oring, and the one i have to replace it just has the rubber oring, would you suggest a cork gasket in addition, as i put it in and tightened it up without the cork as i didnt have one, but before i add coolant i would like to hear how others have done this with the riff raff aluminum housing and the oem thermostat with rubber gasket, i wouldnt think you would need the cork.

 

No cork.

The "newer" style (it's been a "newer" style for many, many years now) has the integrated gasket now as opposed to the old OEM style.

You should be good to go, if everything else is ok.

Stewart

 

sweet, no leak yet just filled still havent started it up yet. also put new belt on.

 

Went to the 203* several years ago and didn't notice any difference. I had to replace my radiator a few months ago I went back to the OEM 195* (from Riffraff) with the "improved" gasket when I did that (along with new hoses). Since I didn't see any difference (and the OEM gasket is better now) I went back.

 

Love my 180* stat...