teamroper1

I have a 2008 f150 with 26,700, the largest engine in it's class, short bed and i do not tow. how often should i change the Differential Fluid.
I have owned trucks for 50 years and don't remember ever changing the fluid and towed horses and trailors all over the southwest. my dealer is pushing me to change. sooo.

Thanks, Teamroper1

Winkzoot

If you are not having problem I would not change it. My owners manual (2005) states that it is not neccessary. Certainly not at 26,700.

Rear axles and power take off (PTO) units containing synthetic lubricant and light duty trucks equipped
with Ford-design axles are lubricated for life. These lubricants are not to be checked or changed unless
a leak is suspected, service is required or the axle assembly has been submerged in water. The axle
and PTO lubricant should be changed anytime the axle and PTO have been submerged in water. During
extended trailer tow operation above 70

be changed anytime an axle has been submerged in water.

2000xl_toronto

I have the same question and felt confused after reading my owners manual. How do we know if our axles were filled with synthetic fluid?

I still plan on changing mine every 60k miles or 5 years as I change all my fluids at that interval.

dewman

I changed the differential fluid in my 96 F150 last summer. The truck had over 150,000 miles at the time and I didn't know if the previous owner had changed it, or not. I did it as a precautionary measure. I would think 100,000 miles would be a good time to change it. It gives you a chance to inspect the diff for any problems and it doesn't hurt it to have fresh oil. If you have a limited slip diff, you will need to add a friction modifier to the gear oil when you change it.

zap

Any of the post 99's will have synthetic from the factory. Run about 60K miles between changes. The stealer is just trying to get you to spend money. My 02 has had 3 fluid changes and currently has 131,000 miles on it. I assume it was changed by the previous owner once or twice but I changed it at 75K miles (8K miles after I got it) just to be sure. Good for 60K miles but I went ahead and changed it again about 6K miles ago when I upgraded the open diff to a lunchbox locker. Cheap insurance, but not need until about 60K miles.

Bear Hunter

If you really want ot know about the condition of your differential gear oil, transmission oil, or engine oil all you need is an oil anlaysis. You can get anlaysis done at Caterpillar dealers, some truck parts stores, usually at Flying "J" truck stops, Speedco truck service businesses or go to Schaefferoil.com and find a dealer or rep in your area. Most vehicles these days have a longer life than the lubricants in them. Lifetime lubricants is not true. Just wait until the warrenty expires and then replace the component. My 2011 F-150 owner's manual says 100,000 or 150,000 miles depending upon the differential manufacturer. I WILL be changing my transmission and differential fluids long before 100,000 miles, just haven't decided yet as to when. My manual also says use synthetic lubes. Synthetic lubes reduce friction and wear and have a longer service life, well worth the small additional cost considering the small quantity needed. Bear Hunter, C. L. S., Society of Tribologists and Lubrication Engineers

flixden

follow the recommended service interval, that's all there is to it. Anything more is waste. The engineers designing these components know better than anybody here.

2000xl_toronto

^^^^

I don't completely agree... the Ford engineers know what maintenance we need to perform to make sure they don't have any warranty claims...

flixden

They want to make sure the truck lasts. It is their long term reputation on the line. A whole bunch of transmission or rear end replacements does not look good for them, and they need buyers.
If the Ford engineers recommend a diff fluid change at 100K miles, then that is just as beyond warranty as 80K or 60K miles would be. And if they say it's never needed, then that also does not help Ford with warranty claim prevention. All it probably really means is that it's never needed.

techrep

iTrader: (1)

Have him show you where it says to change the Diff fluid @ 30K in your owners manual... Tranny yes/brake yes...didn't see Diff.