Notices
6.0L Power Stroke Diesel 2003 - 2007 F250, F350 pickup and F350+ Cab Chassis, 2003 - 2005 Excursion and 2003 - 2009 van

thermostat question

Thread Tools
 
Search this Thread
 
Old Apr 30, 2014 | 01:20 PM
  #1  
KDAVID1's Avatar
KDAVID1
Thread Starter
|
Logistics Pro
Joined: Feb 2013
Posts: 4,073
Likes: 5
From: TX
thermostat question

If you have ECT of 186 and EOT of 194 would changing thermostat tighten that split? ECT should be 190 min. correct?
 
Reply
Old Apr 30, 2014 | 01:31 PM
  #2  
jswartz84's Avatar
jswartz84
Cargo Master
15 Year Member
Joined: Jun 2007
Posts: 2,723
Likes: 5
From: Roseburg, OR
It could, not definite.
 
Reply
Old Apr 30, 2014 | 01:33 PM
  #3  
texastech_diesel's Avatar
texastech_diesel
Token Redneck
15 Year Member
Liked
Loved
Community Favorite
Joined: Jun 2007
Posts: 9,339
Likes: 350
From: Breckenridge, TX
Club FTE Silver Member

I wouldn't mess with changing hardware until you're consistently in the 170s. 4* is as likely to be sensor bias as it is to be the t-stat itself. I've been at 188* for several years now.
 
Reply
Old Apr 30, 2014 | 01:35 PM
  #4  
69cj's Avatar
69cj
Hotshot
20 Year Member
Photogenic
Joined: Jul 2005
Posts: 13,834
Likes: 26
From: Middle Tn.
I would change it out just to get the ect into the 190's or above for better operating efficiency and possibly better mileage.
 
Reply
Old Apr 30, 2014 | 02:32 PM
  #5  
Rusty Axlerod's Avatar
Rusty Axlerod
Lead Driver
15 Year Member
Liked
Loved
Community Favorite
Joined: Feb 2011
Posts: 8,241
Likes: 155
From: L.A. (Lower Alabama)
Club FTE Gold Member
I agree. I think my truck runs better when it's warmer. I fought my own small battle with thermostats awhile back. I've changed mine 4 or 5 times trying to find one that would hold. Seems to me they all eventually start creeping down in temp but the Motorcraft ones do seem to last longer. One of the aftermarkets I tried fell below 185° in just a couple weeks!
 
Reply
Old Apr 30, 2014 | 03:41 PM
  #6  
texastech_diesel's Avatar
texastech_diesel
Token Redneck
15 Year Member
Liked
Loved
Community Favorite
Joined: Jun 2007
Posts: 9,339
Likes: 350
From: Breckenridge, TX
Club FTE Silver Member

^^^ And that's why I wouldn't bother changing it out yet, odds are the replacement will be roughly in the 186-188* range anyways. Compare cold soak temps and swap the sending units before you do anything else to verify a mechanical concern and not just sensor bias.
 
Reply
Old Apr 30, 2014 | 04:08 PM
  #7  
KDAVID1's Avatar
KDAVID1
Thread Starter
|
Logistics Pro
Joined: Feb 2013
Posts: 4,073
Likes: 5
From: TX
I was thinking about the changing to get in higher operating range on ECT. I do notice it does run better and with less split when the ECT temp is stays above 190. I guess my other question would be would EOT raise those extra 4* as well ie: follow the ECT? My cold soak temps are dead even on ECT, EOT, and TFT. With 137K on it--I would say it's time to change it anyway more so to get her heated up a bit more IDK.
 
Reply
Old Apr 30, 2014 | 04:14 PM
  #8  
69cj's Avatar
69cj
Hotshot
20 Year Member
Photogenic
Joined: Jul 2005
Posts: 13,834
Likes: 26
From: Middle Tn.
Originally Posted by KDAVID1
I was thinking about the changing to get in higher operating range on ECT. I do notice it does run better and with less split when the ECT temp is stays above 190. I guess my other question would be would EOT raise those extra 4* as well ie: follow the ECT? My cold soak temps are dead even on ECT, EOT, and TFT. With 137K on it--I would say it's time to change it anyway more so to get her heated up a bit more IDK.
EOT follows the ECT when fully heat saturated. My truck ECT runs consistantly between 197 and 204 depending on ambient and load. There's absolutely no problem with an 8 degree spread. Don't chase rainbows. You'll never catch one.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-1

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-2

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-3

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-4

Every 2026 Ford Engine Explained

 Brett Foote
story-5

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-6

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-7

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-8

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-9

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
Old Apr 30, 2014 | 04:34 PM
  #9  
KDAVID1's Avatar
KDAVID1
Thread Starter
|
Logistics Pro
Joined: Feb 2013
Posts: 4,073
Likes: 5
From: TX
Originally Posted by 69cj
EOT follows the ECT when fully heat saturated. My truck ECT runs consistantly between 197 and 204 depending on ambient and load. There's absolutely no problem with an 8 degree spread. Don't chase rainbows. You'll never catch one.
Not chasing rainbows for sure--not worried about my split at all as it is consistent and within spec. I don't necessarily like the coolant temp down in the 180s for efficiency of course.
 
Reply
Old Apr 30, 2014 | 05:28 PM
  #10  
69cj's Avatar
69cj
Hotshot
20 Year Member
Photogenic
Joined: Jul 2005
Posts: 13,834
Likes: 26
From: Middle Tn.
Originally Posted by KDAVID1
Not chasing rainbows for sure--not worried about my split at all as it is consistent and within spec. I don't necessarily like the coolant temp down in the 180s for efficiency of course.
I agree with you 100% on the low temp. I would try a new Motorcraft if it were mine.
 
Reply
Old Apr 30, 2014 | 05:47 PM
  #11  
KIDkiser's Avatar
KIDkiser
Laughing Gas
Joined: Jun 2011
Posts: 780
Likes: 5
From: Kentucky
EOT will go up also
 
Reply
Old Apr 30, 2014 | 06:43 PM
  #12  
KDAVID1's Avatar
KDAVID1
Thread Starter
|
Logistics Pro
Joined: Feb 2013
Posts: 4,073
Likes: 5
From: TX
Originally Posted by KIDkiser
EOT will go up also
Kinda thought so but wasnt sure
 
Reply
Old Apr 30, 2014 | 06:55 PM
  #13  
allingeneral's Avatar
allingeneral
Mountain Pass
Joined: Mar 2010
Posts: 224
Likes: 2
If you change it out, I'm interested to know if the ECT increases to 190+ or if it turns out to be a sensor bias issue.
 
Reply
Old Apr 30, 2014 | 07:02 PM
  #14  
KDAVID1's Avatar
KDAVID1
Thread Starter
|
Logistics Pro
Joined: Feb 2013
Posts: 4,073
Likes: 5
From: TX
Originally Posted by allingeneral
If you change it out, I'm interested to know if the ECT increases to 190+ or if it turns out to be a sensor bias issue.
Will post up when I do it in a few weeks when I change the oil and such. I'm ruling out a sensor as all three temps are the same after 12 hour cold soak and within a degree of ambient so I would say the sensors are calibrated exact I would think. Could be wrong though
 
Reply
Old Apr 30, 2014 | 08:14 PM
  #15  
steelhead2's Avatar
steelhead2
Posting Guru
Joined: Jan 2009
Posts: 1,328
Likes: 0
Its 4* off. 4* will not make any difference at all. And yes, eot will follow.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bcaughhorn
1999 - 2003 7.3L Power Stroke Diesel
1
Dec 7, 2010 09:23 AM
havns3
6.0L Power Stroke Diesel
2
Aug 11, 2010 05:19 PM
ktahelton
1999 - 2003 7.3L Power Stroke Diesel
5
May 1, 2006 12:15 AM
BigMacZack
Cooling, Heating, Ventilation & A/C
1
Jan 19, 2004 01:11 PM




All times are GMT -5. The time now is 11:47 PM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE