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

Low oil temperature

Thread Tools
 
Search this Thread
 
Old Feb 6, 2016 | 08:46 PM
  #1  
cinrock's Avatar
cinrock
Thread Starter
|
Freshman User
Joined: May 2011
Posts: 41
Likes: 0
From: South Carolina
Low oil temperature

I've had a Scan Gauge II in the truck for the last 3+ years and usually have it showing ECT EOT FICM main power and volts. For all that time, my numbers have been normal until last month. With the engine up to temperature (ECT at 190 or higher), my EOT is lagging behind - sometimes 20* cooler. I've also noticed the EOT jumping around for no apparent reason.

From what I understand of the 6.0 cooling system, the oil is cooled by the coolant and what I'm seeing shouldn't happen if the engine is up to temperature. The obvious fix is to swap out the EOT sensor but I figured I'd ask the experts first. Any thoughts?

2005 dually crew cab with 105k.
 
Reply
Old Feb 6, 2016 | 08:59 PM
  #2  
navistarnut's Avatar
navistarnut
Postmaster
Joined: Aug 2015
Posts: 3,910
Likes: 18
From: NW IA
Originally Posted by cinrock
I've had a Scan Gauge II in the truck for the last 3+ years and usually have it showing ECT EOT FICM main power and volts. For all that time, my numbers have been normal until last month. With the engine up to temperature (ECT at 190 or higher), my EOT is lagging behind - sometimes 20* cooler. I've also noticed the EOT jumping around for no apparent reason.

From what I understand of the 6.0 cooling system, the oil is cooled by the coolant and what I'm seeing shouldn't happen if the engine is up to temperature. The obvious fix is to swap out the EOT sensor but I figured I'd ask the experts first. Any thoughts?

2005 dually crew cab with 105k.
I would be curious what your EOT and ECT are reading after a cold soak of 24 hours.

Also, have you tried swapping the plugs around to see the result?
 
Reply
Old Feb 7, 2016 | 07:24 AM
  #3  
cinrock's Avatar
cinrock
Thread Starter
|
Freshman User
Joined: May 2011
Posts: 41
Likes: 0
From: South Carolina
Thanks Mike

Have to wait until Monday for a true cold soak and I'll check the readings before starting. Last time I checked after a cold soak they were 1.5* apart from each other. Don't recall which was higher.

Swapping the connectors between the ECT and EOT is a great idea. If the temp differential is OK when cold, I'll definitely try that. The EOT sensor is less than 2 years old. It was replaced by Ford as a source for a nagging oil leak, maybe I got a lemon!
 
Reply
Old Feb 7, 2016 | 07:56 AM
  #4  
Jmoen7's Avatar
Jmoen7
Laughing Gas
Joined: Oct 2012
Posts: 794
Likes: 1
From: Ontario
Thermostat could be sticking, but you would likely see higher coolant temps than 190. Maybe partially sticking? If the sensors are good, once the stat opens your oil should go above your coolant temperature.
 
Reply
Old Feb 7, 2016 | 08:02 AM
  #5  
FiveOJester's Avatar
FiveOJester
Fleet Mechanic
15 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Sep 2006
Posts: 1,491
Likes: 295
From: Fresno, CA
Jumping around sounds like either a bad sensor or a wiring issue.

It's the same sensor as the ECT so swap the sensors.
 
Reply
Old Feb 7, 2016 | 08:07 AM
  #6  
69cj's Avatar
69cj
Hotshot
20 Year Member
Photogenic
Joined: Jul 2005
Posts: 13,834
Likes: 26
From: Middle Tn.
Mine did the same thing. Took off the connector, cleaned sensor pin and reinstalled with a light coating of dielectric grease. No problem after that. If it was the t-stat the ect would also be wacked.
 
Reply
Old Feb 8, 2016 | 12:20 PM
  #7  
cinrock's Avatar
cinrock
Thread Starter
|
Freshman User
Joined: May 2011
Posts: 41
Likes: 0
From: South Carolina
I checked the temperature differential after a cold soak and they were within 1 degree of each other. I did remove the connector and cleaned it out on the pretense that there may have been some oil residual in there when the old sensor was leaking oil. Got it up to 170 degrees on a short trip yesterday with no fluctuation so I may be on to something. Gotta pick up some dielectric grease though....

Thanks all!
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
snotrod
6.0L Power Stroke Diesel
8
Nov 14, 2016 09:18 PM
juanrodriguez
6.0L Power Stroke Diesel
53
May 30, 2015 01:44 PM
Undone
6.0L Power Stroke Diesel
38
Jun 13, 2013 09:52 AM
carmk
6.0L Power Stroke Diesel
5
Apr 18, 2012 08:27 AM
69cj
6.0L Power Stroke Diesel
15
Dec 24, 2011 07:39 PM




All times are GMT -5. The time now is 06:54 AM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
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-3
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-4
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-5
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-6
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-7
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-8
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-9
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