2010 4WD - Service Intervals diffs and transfer case

[grfo]

The service guide says to do the front diff and transfer case fluids @ 150k miles.
No mention of the rear diff in the service guide.

Changing out the differential gear oil (both front and rear) as well as the transfer case fluid was easy to do (just a bit messy!). As noted in other posts - the transfer case and rear diff have drain and fill plugs, so, it's very easy and quick. The front diff has only a fill plug and the gear oil has to be sucked out or pull the cover. I took the sucky method

My 2010 V8 4WD has 110k miles on it - it has lived most of it's life in eastern NC - so it's not been used much in 4WD mode I would guess.

Front diff gear oil really didn't need to be changed from appearances - it was cloudy but looked good, no funky smell.

Rear diff, definitely needed to be changed. Both magnetic plugs (drain and fill) were loaded up with filings. The fluid was very dark.

The big surprise was the transfer case fluid - it was nasty! Considering the transfer case fluid appears to be ATF (cherry red) - it was black coming out of the case! I am surprised that the service interval is 150k miles - I would strongly recommend anyone with a 4WD to change it out every 30-50k.

Why was the transfer case fluid so nasty if the 4WD (apparently) hasn't been engaged that frequently??

 

[thebrakeman]

I don't know a ton about the inner-workings. However, since the days of manual-locking hubs, all of the bits are still turning, right? Even if the auto-4WD never engaged at all, the front hubs, CV shafts, front diff, and front drive shaft are all spinning 100% of drive time, right? The only difference is that torque isn't transmitted thru those bits until rear wheel spin is detected, or you force it to be locked. But when not, the bits are still turning against each other, with opportunity to wear the components, as well as "shear" the fluids.

Plus, being in Auto-mode, it's probably been engaged more than you know. Take off hard on wet pavement, and things are probably calibrated to have 4WD kick in before traction control.

Again, I'm just thinking about-loud here. Don't make me feel bad if I'm off-base.

 

[gdgiordano]

My tranny fluid has been done at least twice in 115k. Was very dark when last changed. My t case was cloud but ok. I was told my rear end looks good. Haven’t checked the front.

I will be doing trans every 40-50 and I might let the t case go 70-80. Ford recommendations on this blow.

 

[07EddyB]

Considering the transfer case fluid appears to be ATF (cherry red)

Wait - you seem to be unsure about the transfer case using ATF yet you changed it? That statement confuses me - I hope you put ATF back in it!

 

[grfo]

Wait - you seem to be unsure about the transfer case using ATF yet you changed it? That statement confuses me - I hope you put ATF back in it!

2010 specifies Ford Transfer Case Fluid - which appears to be ATF (cherry red appearance, might be ATF for all I know).

I know previous years they specified Mercon V.

I put Motorcraft Transfer Case Fluid in it.

 

[BKennedy]

I change the transfer case and differential fluids the same time I do the transmission, every 50,000 miles for a daily driver type vehicle. I know a guy who has owned a transmission shop for over 40 years and seems to have forgotten more than we will ever know about them. That is the schedule he recommends, but only for the parts you don't want to spend money having rebuilt. I have LubeLocker gaskets on transmissions and differentials so it makes changing fluids not so much of a chore. Transmissions have aftermarket drain plugs in pans.

For my Explorer, which usually gets 1000-3000 miles per year; I check the transfer case fluid. If it looks pink and clear I leave it alone. Transmission gets pan drop, filter change and partial fluid change (6-7 quarts) every other year. I use Mobile 1 ATF for both of those (I have a GM 700R4 transmission and a NP231 transfer case). Engine gets one oil change per year. Differentials are on same schedule as transmission except I check the levels several times a year and check for contamination after any water crossings that are deeper than the bottom of the hubs.

 

[PotatoExplorer]

2010 specifies Ford Transfer Case Fluid - which appears to be ATF (cherry red appearance, might be ATF for all I know).

I know previous years they specified Mercon V.

I put Motorcraft Transfer Case Fluid in it.

I used a Valvoline TCF since it was the only thing on the shelf that said it could be used in place of XL-12. I'd think the 2008's are the same as the 2010's?
Transfer case fluid: XL-12 or Mercon V

 

[gdgiordano]

I will be doing mine every 50 since I go about 3k miles a month lol.

 

[07EddyB]

2010 specifies Ford Transfer Case Fluid - which appears to be ATF (cherry red appearance, might be ATF for all I know).

I know previous years they specified Mercon V.

I put Motorcraft Transfer Case Fluid in it.

Gotcha - my 2007 calls for ATF. Didn't know they changed the specs.
Thanks for reminding me that I need to change mine. It is now on the list for this weekend or later or when I get around to it or much later than I had planned. That's the way it goes unfortunately.

 

[Littleant]

grfo you installed the correct fluid perfect. Transfer case fluid is the correct fluid. NOT ATF Mercon 5. Dip a finger in the . Transfer case fluid then the Mercon 5 you will feel the difference.

 

[CDW6212R]

I try to change the transfer case fluid once a year in my trucks. The Ford shop foreman suggested that when I bought my Mercury(AWD) 14 years ago. It holds so little and it's so quick to do, I like to be sure that's well kept, the TC is not cheap to replace.

The fluid for TC's seems to be the old Mercon ATF fluid, or the new TC only XL-12 Ford came out with, due to issues with using Mercon V. The new TC fluid evidently is applicable to any TC of any model that used an ATF. But the reports suggest that it is basically the same as the old Mercon. So if you don't like the way high price of the new TC fluid, the old Mercon(still available as Dexron III(states on it meets Mercon specs)), is available everywhere, and relatively cheap. I still have a few bottles of actual Mercon/Dexron III. I think it's time for me to use a bottle of that in my 98 again.