2005 F250 with 125k miles, just recently purchased. Should I change my rear end fluid? No issues. Pulled out plug last night and all looks fine, just curious if I should add this to my "new-to-me truck To Do" list.

 

I would check the owner's manual.

 

Could be a used water truck... If so, you definitely need to replace the rear diff and front diff (if it has one).
I had a 2006 4x4 (bought new) and the rear diff had a metal tag on it that said something like: Synthetic Do not replace, Do not inspect.

But that's if all is well and no suspected of anything.

Many water (flood) vehicles are coming out of hurricane states. Do be careful... The truck could have been sitting in water up to the bumper for days or weeks.

This forum has someone who wrote in and found water inside his rear diff.

 

I am old school

change gear lube every 50,000 miles..

you change the motor oil..
change transmission fluid, final gear lube, brake fluid, power steering fluid. no fluid last forever...

my opinion, money well spent.

 

 

 

If there are no maintenance records on your truck then change it. It’s a simple job.

 

Thanks. As far as the diff cover gaskets go, permatex or the OEM gasket?

 

 

Yep, change it.... Wipe any metal fragments out.. Clean the ABS Sensor..

 

 

 

Check the below for the correct rear diff oil....

6.7L Power Stroke Maintenance Schedule

Service Procedure
Service Interval(s)
Replace engine oil & oil filter
10,000 miles or as indicated by the instrument cluster message center
(Intelligent Oil Life Monitor system will adjust interval to driving conditions)
Replace fuel filter
22,500 miles or as indicated by the instrument cluster message center
15,000 hours/6 months/600 hours under severe duty conditions
Replace engine air filter
45,000 miles or as necessary
(inspect at oil change intervals)
Flush engine cooling system
Initial flush at 105,000 miles/6 years followed by 45,000 miles/3 year subsequent service intervals
60,000 miles/2,400 hour initial flush under severe duty conditions
Replace automatic transmission fluid & filter
150,000 miles
Replace transfer case fluid
150,000 miles under normal conditions
60,000 miles under severe duty conditions
Replace front differential fluid (4x4)
150,000 miles under normal conditions
50,000 miles under severe duty conditions
Replace rear differential fluid
100,000 miles under normal conditions
50,000 miles under severe duty conditions

6.7L Power Stroke Service Part Numbers

Note - Select part numbers may not be applicable to 2017 model year trucks.Engine air filter
Pre-filter
Motorcraft FA-1909 (Ford BC3Z-9601-D, replaces FA-1907)
Air filter
Motorcraft FA-1902 (Ford BC3Z-9601-A)
Engine oil filter
Motorcraft FL-2051S (Ford BC3Z-6731-B)
Engine oil fill cap
Motorcraft EC-786 (Ford EC3Z-6766-A, Motorcraft EC-780)
Fuel filter set
2011 - 2016
Motorcraft FD-4615 (Ford BC3Z-9N184-B)
2017
Motorcraft FG-1117
Glow plug[1]
2011 - 2012
(12/1/2012 cutoff date)
Motorcraft ZD-17 (Ford BC3Z-12A342-B)
2012 - 2016
Motorcraft ZD-18 (Ford BC3Z-12A342-C)
Thermostat
Motorcraft RT-1231 (Ford BC3Z-8575-D)
Cam sensor
Motorcraft DU-92 (Ford BC3Z-12K073-A)
Crank sensor
Motorcraft DY-1148 (Ford BC3Z-6C315-A)
Automatic transmission filter
(TorqShift 6R140, 6 spd)
Motorcraft FT-187 (Ford BC3Z-7A098-B)

6.7L Power Stroke Oil/Fluid Specs & Capacities

Oil & Fluid Specs

Engine oil
10W-30
Acceptable viscosity in ambient temps > 0° F
(Preferred for normal usage)
5W-40
Acceptable viscosity in ambient temps > -20° F
(Trucks using biodiesel should use 15W-40 or 5W-40)
(Preferred if truck falls under "Severe Duty" service schedule)
15W-40
Acceptable viscosity in ambient temps > 20° F
(Trucks using biodiesel should use 15W-40 or 5W-40)
0W-30/0W-40
Acceptable viscosity in all ambient temperatures
(Recommended in extremely cold conditions only)
Engine coolant
Motorcraft Orange Engine Coolant, VC-3DIL-B
(50/50 coolant-distilled water mixture if using concentrated fluid)
Automatic transmission fluid
Motorcraft MERCON LV automatic transmission fluid (ATF)
Transfer case fluid
2011 - 2016

Motorcraft XL-12 transfer case fluid
2017
Motorcraft MERCON LV automatic transmission fluid
Front differential fluid
SAE 80W-90 gear oil
Rear differential fluid[2]
Sterling 10.50"
(F-250, SRW F-350)
2011 - 2016

SAE 75W-140 full synthetic gear oil
2017
SAE 75W-85 full synthetic hypoid gear oil
Dana 80
(DRW F-350)
SAE 75W-90 full synthetic gear oil
Dana S110/S130
(F-450, F-550)
SAE 75W-140 full synthetic gear oil
Dana M275
SAE 75W-140 full synthetic gear oil
Dana M300
SAE 75W-140 full synthetic gear oil

Oil & Fluid Capacities

Fluid capacities are nominal - always fill to proper level on dipstick or to fill plug level as applicable.
All measurements in U.S. quarts ("qts") and/or pints ("pts"), NOT Imperial.
Engine oil capacity
13 qts w/ filter
Engine Cooling system capacity[3]
29 - 35 qts, varies by model year (7.25 - 8.75 gallons)
DEF Tank Capacity
2011 - 2016 pickup
5 gallons
2017 pickup
7.4 gallons
2011 - 2016 chassis cab
6 gallons
2017 chassis cab
7.2 gallons
Automatic transmission fluid capacity
17.4 to 18.5 qts (approximate dry fill capacity)
Transfer case fluid capacity
2.0 qts, 1.9 liters
Front differential oil capacity[4]
2.9 qts, 5.8 pts, 2.8 liters
Rear differential fluid capacity[4]
Sterling 10.50"
3.5 qts, 6.9 pts, 3.3 liters

Dana 80
4.25 qts, 8.5 pts, 4.0 liters
Dana S110/S130
7 qts, 14.0 pts, 6.6 liters
Dana M275
3.8 qts, 7.6 pts
Dana M300
4.5 qts, 9 pts

[1] Verify correct glow plug for application. Engines built before 12/1/2012 require ZD-17 glow plugs, while later engines require ZD-18 glow plugs. ZD-17 glow plugs are 91 mm long, while the later ZD-18 glow plugs are 96 mm long; only use the correct glow plug for your engine.
[2] Limited slip differentials may require a supplemental friction modifier - use Motorcraft XL-3)
[3] Nominal primary engine cooling circuit capacity. Because the 6.7L Power Stroke is equipped with an air-to-water charge air cooler (intercooler), it features a second cooling circuit.
[4] Nominal differential oil capacity. Always fill axle to fill plug level and do not rely on the oil capacity as the actual refill capacity. Use provided figures as a reference to obtain the necessary fluid quantity only.

 

Thanks, that’s great info to have.

I know the spec is SAE full synth 75w140...I’m just wanting to know if it’s critical to go with Motorcraft brand. I know with coolant and tranny fluid, that’s the way to go even though there are other “compatible” options.

 

The only critical item to the rear end lube is whether you have a limited slip or open rear chunk. If you have a limited slip, you need to add a friction modifier to the gear lube. not sure what the ratio is but the owner's manual should tell you.