203* T-Stat
Hotshot
Joined: Oct 2003
Posts: 17,791
Likes: 99
From: Ashland City, TN
All T-444e engines have a 203 T-stat. Why ford switched to a cooler one. I'll never know.
Some say 203 is better, some claim the other is better.
Joey says with the dual pumps, you should run a cooler t-stat, cause the oil heats up quicker with the pumps.
And I think I recall Bill saying our trucks run really good at 230.
Some say 203 is better, some claim the other is better.
Joey says with the dual pumps, you should run a cooler t-stat, cause the oil heats up quicker with the pumps.
And I think I recall Bill saying our trucks run really good at 230.
Hotshot
Joined: Dec 2005
Posts: 10,246
Likes: 7,658
From: Chino Valley, Arizona
I have bought 2 of them, the one I put in my '97 runs 170 to180 not as hot as the 195 I had before. the one I put in the customers truck runs over 200. but I don't know if performance changed on that one. I would assume it did as the old thermostat was stuck open.
so from my experience 50% success! I won't be spending the money on a 203 thermostat anymore
so from my experience 50% success! I won't be spending the money on a 203 thermostat anymore
PREMIUM SPONSOR
Joined: Sep 2003
Posts: 2,630
Likes: 217
From: North East Ohio
I went through several stats in a month from the parts stores, then I bought the 203° from Dieslesite and it's been working perfectly for about 1.5 years.
As for benefits, like William said all IH T444E had the 203° stat, Ford went to a cooler stat probably to lower overall cooling due to smaller radiator, etc.
I don't see any drastic changes with mine in either truck, but IMO if IH meant them to have 203 then mine will get 203.
Diesels run on heat not spark, those few degrees have to help....
As for benefits, like William said all IH T444E had the 203° stat, Ford went to a cooler stat probably to lower overall cooling due to smaller radiator, etc.
I don't see any drastic changes with mine in either truck, but IMO if IH meant them to have 203 then mine will get 203.
Diesels run on heat not spark, those few degrees have to help....
__________________
'96 7.3 F-350 Reg Cab 4x4 - bought new.
'04 6.0 E-350 custom 4x4
'08 6.4 F-550 Reg Cab 6 spd 4x4
'17 6.7 F-250 KR ccsb 4x4
'96 7.3 F-350 Reg Cab 4x4 - bought new.
'04 6.0 E-350 custom 4x4
'08 6.4 F-550 Reg Cab 6 spd 4x4
'17 6.7 F-250 KR ccsb 4x4
Postmaster
Joined: Sep 2007
Posts: 4,195
Likes: 6
From: Medford Oregon
That being said the engine won't heat up any faster because you have a 203* stat. But I can tell you when watching on a scanner once you hit the 170* it does not take long to get up into the 190* to 200* range with the 203* stat, in summer months.
Might be my imagination but gut feeling is Ford did it for emissions at idle. Truck just does not seem to perform as well in the 170* range and as soon as I get it above the range, injectors quiet down a bit. Probably a timing thing.
Fleet Owner
Joined: Aug 2004
Posts: 20,418
Likes: 197
From: AZ
My oil temp and water temp's are not close at all when pulling hard. The water temp will stay about 200* or so but the oil will go up to 230* or more. Bob at Dieselsite told me it supposed to do that???
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PREMIUM SPONSOR
Joined: Sep 2003
Posts: 2,630
Likes: 217
From: North East Ohio
On the freeway, not towing/hauling just cruising I see oil temps around 218°, with water temps around 200°.
We have the same oil cooler as the T444E, only difference is the radiator/water cooling.
Now maybe with dual or larger HPOP you might want to keep water temps down to keep oil temps down, but in a stock-ish platform I see nothing 'wrong' with running what's supposed to be there.
We have the same oil cooler as the T444E, only difference is the radiator/water cooling.
Now maybe with dual or larger HPOP you might want to keep water temps down to keep oil temps down, but in a stock-ish platform I see nothing 'wrong' with running what's supposed to be there.
__________________
'96 7.3 F-350 Reg Cab 4x4 - bought new.
'04 6.0 E-350 custom 4x4
'08 6.4 F-550 Reg Cab 6 spd 4x4
'17 6.7 F-250 KR ccsb 4x4
'96 7.3 F-350 Reg Cab 4x4 - bought new.
'04 6.0 E-350 custom 4x4
'08 6.4 F-550 Reg Cab 6 spd 4x4
'17 6.7 F-250 KR ccsb 4x4
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Logistics Pro
Joined: Oct 2008
Posts: 4,818
Likes: 1
From: Avilla, IN
I love the 203. My 195 was stuck open, so thats what I am comparing to. I actually have to turn off the cab heat on a zero degree day now.
I also have to agree that the truck runs alot better when it gets up there in temp. I don't have an aftermarket guage, but there is definately a difference in the way the engine runs with the needle on the 'R' vs. barely on the 'N.'
Any PSD I buy in the future will get one.
I also have to agree that the truck runs alot better when it gets up there in temp. I don't have an aftermarket guage, but there is definately a difference in the way the engine runs with the needle on the 'R' vs. barely on the 'N.'
Any PSD I buy in the future will get one.
Cargo Master
Joined: Jul 2006
Posts: 2,756
Likes: 38
From: Nampa, ID
I'm in the same boat as Phil. I don't have aftermarket gauges either and my old 195* was stuck open. Temp range wouldn't make it to the "N" in an Idaho winter. Summer, it would barely get to the "O" on a good day.
Now, the 203* runs consistently between "M" and "A" in any weather. Engine seems smoother, too. Most times, if I run the heater, I have to switch the fan back to low and set the temp switch one or two clicks into the blue.
Haven't been able to afford filling the tanks, but what I put in "seems" to run much longer. Wife needed her car last night (I'm a shift worker) so I took the truck. Put $20 in the empty (rear) tank and ran on the front tank. It was in the red when I left for work. Made it to and from work (45 miles round trip) and didn't need to switch tanks yet.
Now, the 203* runs consistently between "M" and "A" in any weather. Engine seems smoother, too. Most times, if I run the heater, I have to switch the fan back to low and set the temp switch one or two clicks into the blue.
Haven't been able to afford filling the tanks, but what I put in "seems" to run much longer. Wife needed her car last night (I'm a shift worker) so I took the truck. Put $20 in the empty (rear) tank and ran on the front tank. It was in the red when I left for work. Made it to and from work (45 miles round trip) and didn't need to switch tanks yet.
Posting Guru
Joined: Aug 2002
Posts: 1,729
Likes: 2
I bought two. Put one in my 96 but only put 140 miles on it since installed 7 months ago. Truck always ran in the 0-R area while plowing snow and hauling rock. Only thing I really noticed so far is running between R-A when going hard w/a load.
Haven't installed the one on my 97 yet, but the current stat must be stuck. Pulling 18k lbs only ever saw O w/the A/C on and 95* outside.
Haven't installed the one on my 97 yet, but the current stat must be stuck. Pulling 18k lbs only ever saw O w/the A/C on and 95* outside.
Hotshot
Joined: Feb 2009
Posts: 10,408
Likes: 75
From: Plankinton, SD
Mine always ran cool like others but when I changed my pump out last year I put a new stat in and the old one was 182. I put in the 195, temp rose about a letter between the r and m when I'm towing. Seems to work good to me.
