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203* T-Stat??

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Old Sep 11, 2009 | 06:27 PM
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Wink 203* T-Stat??

I just read on anouther thread that some folks are disapointed in the 203* T-Stat.....I swapped mine about 2 years ago shortly after I bought my LATE '99 along with the Billet housing......what seems to be the problem?? are those that tow heavy loads alot getting too warm? mileage decrease? power decrease?
 
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Old Sep 11, 2009 | 06:31 PM
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IMO, running a 203 'stat is only good in the frozen north.
Ford's stock temperature used to be 195 and now it's 192 or something like that.
They had a reason for lowering it.
.
 
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Old Sep 11, 2009 | 06:48 PM
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Originally Posted by Kwikkordead
IMO, running a 203 'stat is only good in the frozen north.
Ford's stock temperature used to be 195 and now it's 192 or something like that.
They had a reason for lowering it.
.
Yeah, the reason was emissions.
 
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Old Sep 11, 2009 | 06:52 PM
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Yep -- it's 192. I have one in mine. EOTs run in the upper 180s to a max I've seen so far of exactly 192...
 
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Old Sep 11, 2009 | 06:53 PM
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subscribing.....
 
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Old Sep 11, 2009 | 07:50 PM
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I changed mine in June, along w/coolant. Haven't seen any problems or benefits to
this point, but am hoping to see better mileage this winter. (Wisconsin)
 
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Old Sep 11, 2009 | 08:07 PM
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Just an observation but I changed my oil with Rotella 5w-40 syn before I went on our trip down south, about 568 miles one way and loaded heavy, towing about 8000 with about 300-400 pounds in the back. My truck ran flawlessly in the 85* to 97* degree weather we had. I noticed my oil got darker quicker because of the heavy towing but i,m wondering if my 203* stat cooked the oil a little more because of the temp. change between the stock and 203*. On my next oil change, I'll monitor the change in oil consistencey and color to see if theres a difference. Ran the stock stat for so long, I know when the oil starts discoloring from normal use. Maybe even do a UOA on it. Subscribing..
 
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Old Sep 11, 2009 | 10:02 PM
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Originally Posted by clux
Yeah, the reason was emissions.
NOX control?
 
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Old Sep 12, 2009 | 07:21 AM
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Originally Posted by Kwikkordead
NOX control?
You got it.
 
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Old Sep 12, 2009 | 07:27 AM
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I have had a 203 Tstat in my truck for 2 yrs now. I probably tow as much or more than most. average 26,000 lbs truck and trailer. the idea behind the hotter temps was more complete combustion. diesels run off heat right? Coming out of Skagway AK it 11% grade for 11 miles! never even attempted to overheat. long pulls across the Blues in Oregon nothing! the most I've see my guage move is 1/8 in. Now that being said I also run the Evans waterless coolant and a zero pressure cap. Seems like the system works for me.

Barney
 
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Old Sep 12, 2009 | 08:28 AM
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I never had any coolant overheating problems (Peak Final Charge ELC; 50/50 mix), but during my live tuning, it was discovered that my engine oil temperature was a bit too high for Jody's liking. We discussed this and I have since switched back to the OEM 195* thermostat. Now, my EOT is within the normal range. Under a load, I feel, the temps will get plenty hot enough to be efficient without being excessive.
 
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Old Sep 12, 2009 | 08:49 AM
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Don't think it was the HPOP working its guts out trying to keep up with the tunes that caused the oil temps to be high?

Barney
 
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Old Sep 12, 2009 | 09:06 AM
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No, Barney, the oil cooler's job in cold weather is also to warm up the oil via heat exchange in the oil cooler.
Hotter coolant will always = hotter oil.
I'm not saying that an HPOP working hard isn't a factor.
 
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Old Sep 12, 2009 | 10:02 AM
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I guess I'll have to hook up the AE and watch it while Cheryl drives next time. What is the optimum oil temp? I realize cooler is better,but what is desired? While we're on the subject, does 10 degrees in water temp really make that much difference?
Barney
 
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Old Sep 12, 2009 | 10:12 AM
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Yep -- watch that EOT. I'm curious what y'all are seeing with the 203 'stat. I already posted my "normal" temps above. What were you seeing, Roland?
 
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