Damage from not driving?
Post Fiend
Joined: Mar 2009
Posts: 11,798
Likes: 14
From: Mt. Shasta California
A hotter than normal thermostat is a bad idea. That truck isn't always going to go 10 blocks for starters.
Post Fiend
Joined: Mar 2009
Posts: 11,798
Likes: 14
From: Mt. Shasta California
1) use the engine heater
2) Use Rotella synthetic
3) Once a week someone else drive it
My 2000 7.3 doesn't get driven but about twice a week but each time it is driven about 30 miles or more. I use the Rotella synthetic. Mine ALWAYS gets warmed up.
You are asking for carbon build, sludge and other bad things not to mention water in the separator and fuel alga
2) Use Rotella synthetic
3) Once a week someone else drive it
My 2000 7.3 doesn't get driven but about twice a week but each time it is driven about 30 miles or more. I use the Rotella synthetic. Mine ALWAYS gets warmed up.
You are asking for carbon build, sludge and other bad things not to mention water in the separator and fuel alga
Wiser by FTE
Joined: Jan 2010
Posts: 2,837
Likes: 48
Senior User
Joined: Oct 2008
Posts: 367
Likes: 0
From: Plover, WI
Also, my recommendation of a hotter thermostat comes from my own experiences with a 1.5 mile commute daily, longer trips a few times a year, and some moderate 10-12k lb towing. Never had a problem overheating at 100° in summer or thru Wyoming mountains towing. Oil samples all improved across the board after the hotter tstat.
Post Fiend
Joined: Mar 2009
Posts: 11,798
Likes: 14
From: Mt. Shasta California
Price wise on the oil I agree. Protection wise, I still feel synthetic handles the 'abuse' of short trips better over the vehicles lifetime.
Also, my recommendation of a hotter thermostat comes from my own experiences with a 1.5 mile commute daily, longer trips a few times a year, and some moderate 10-12k lb towing. Never had a problem overheating at 100° in summer or thru Wyoming mountains towing. Oil samples all improved across the board after the hotter tstat.
Also, my recommendation of a hotter thermostat comes from my own experiences with a 1.5 mile commute daily, longer trips a few times a year, and some moderate 10-12k lb towing. Never had a problem overheating at 100° in summer or thru Wyoming mountains towing. Oil samples all improved across the board after the hotter tstat.
Junior User
Joined: May 2012
Posts: 84
Likes: 0
Check your Thermostats, even if you don't like a 203* having a working one will do wonders on a 7.3 vs. a stuck open or broken thermostat. I got mine from Diesielsite with the aluminum housing, did wonders on my 7.3 EX.
The science is well behind the peak performance of a diesel is hotter then 192 or 195.
WHY IS 203° BETTER THAN 195°?
Diesels run most efficiently at approximately 200° or above. A factory equipped 192°/195° thermostat will maintain an operating temperature at approximately 165°-170°. The Powerstroke has such an efficient cooling system, that this low flow when the thermostat is slightly open is normally enough to keep the engine cool. The downfall to this is that the engine -- when our trucks are not under load -- never begins to reach its optimal operating temperature. Our 203° thermostat maintains a minimum operating temperature of 190°. This brings the operating temps up from as low as 170° to as high as 203° depending on the operating conditions of the truck. This is closer to the operating temperature range that is preferable in our trucks for optimal efficiency.
When our trucks are under load and are producing higher combustion temperatures the 203° will allow the engine to run even closer to its optimal operating temperature. If the truck is under load and reaches the 203° setting, the thermostat is then fully open. This means you are at the maximum coolant temperature that the truck will reach. Your maximum temperatures are only a few degrees higher than in stock configuration, but these are degrees that you want for better performance. The best benefits come when the same truck is under a light load and would have a hard time reaching this optimal temperature. As stated above, you will never reach this optimum temperature with the stock 195° thermostat. The end result of installing the 203° thermostat should be slightly better fuel economy, less smoke, and maybe a few extra "ponies" to go along with it.
Question: Why do I want my truck to run warmer?
Answer: You want the engine oil/water temps to be warmer so you get a cleaner, more complete combustion. This can actually bring exhaust gas temperatures DOWN. Diesel ignites from heat of compression. The idea is to compress the air charge to build enough heat to light the fuel, but if it's fighting against a low engine heat, the fuel will ignite, but not as complete as if the cylinders were just a bit warmer. The more complete the combustion, the cooler the exhaust temperatures. Diesel fuel combustion tends to complete best at temps above 200°. An added benefit from using the 203° thermostat is better working cab heaters in the cold months. Another added benefit is better fuel economy. We have seen everywhere from 1-4mpg increases. This depends on climates, driving habits, etc. Even a modest .25 mpg increase will pay for the thermostat in a few miles.
For anyone who doesn't think 8 degrees can make a difference, consider that at 211 degrees water is hot, at 212 degrees, its converted to vapor. At the right critical point for every matter on earth, a degree or a few degrees can make a HUGE DIFFERENCE.
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Junior User
Joined: May 2012
Posts: 84
Likes: 0
I don't know any of the reasons they changed in the 1st place, guessing emissions and EPA but I really don't know. 213 is 2 close to boiling for my comfort. 203 seems like a decent compromise between the 2. Diesels like the heat but boiling isn't a very good option either.
Super Moderator
Joined: May 2004
Posts: 29,380
Likes: 118
From: Central Coast of CA
I like Bob and am a customer of Dieselsite, but I removed the 203* thermo I put on my Excursion because it allowed my engine to run too hot. I went back to the stock thermo.
The 203* might be good for those that live in cold climates, and there are those that like the thermostat, but the stock thermo works better for me and my rigs.
Stewart
Post Fiend
Joined: Mar 2009
Posts: 11,798
Likes: 14
From: Mt. Shasta California
I disagree.
I like Bob and am a customer of Dieselsite, but I removed the 203* thermo I put on my Excursion because it allowed my engine to run too hot. I went back to the stock thermo.
The 203* might be good for those that live in cold climates, and there are those that like the thermostat, but the stock thermo works better for me and my rigs.
Stewart
I like Bob and am a customer of Dieselsite, but I removed the 203* thermo I put on my Excursion because it allowed my engine to run too hot. I went back to the stock thermo.
The 203* might be good for those that live in cold climates, and there are those that like the thermostat, but the stock thermo works better for me and my rigs.
Stewart
Tuned
Joined: Nov 2013
Posts: 255
Likes: 3
From: Hamilton Ontario
The boiling point of 50/50 Whater/antifreeze at 15 PSI is around 275F
I run a 203F in my TDI and have never seen it hit over 200 but gets 60 miles more on a 14 gallon tank.
But that's not the same beast as a 7.3 powerstroke
So your milage and temperatures may vary
I run a 203F in my TDI and have never seen it hit over 200 but gets 60 miles more on a 14 gallon tank.
But that's not the same beast as a 7.3 powerstroke
So your milage and temperatures may vary
Senior User
Joined: Oct 2008
Posts: 367
Likes: 0
From: Plover, WI
I think the main reason for the change out was to avoid people pushing them too hard for too long, and avoiding warranty issues. The 'hammer down' mentality that being able to tow whatever you want as fast as you want will burn anything up.
is a BAAAD MAN
Joined: Apr 2005
Posts: 3,738
Likes: 5
From: Winston Salem NC
I disagree. I like Bob and am a customer of Dieselsite, but I removed the 203* thermo I put on my Excursion because it allowed my engine to run too hot. I went back to the stock thermo. The 203* might be good for those that live in cold climates, and there are those that like the thermostat, but the stock thermo works better for me and my rigs. Stewart