Fellas,
I am having trouble finding information on how often we service the transfer case and differential (front & rear-4x4). My truck has 124k miles on it. I just want to make sure that I am not neglecting anything as far as longevity & maintenance goes. How often should the transfer case & diff be done?

Also, is their anything else other than oil, oil fitler, fuel filters, transmission fluid/filters, air filter, and coolant that should be serviced (main things)? Looks like most 6.0 oweners all have less than 100k miles, and i don't see where many talk about service & TLC at the higher mileage. Thanks, any input would be greatly appreciated.

2005 Fx4, 124k miles, ARP studs, coolant filter, 4" tb exhaust, sctx3-dptuned, afe intake

 

What previous intervals have you performed?

Do you have the manual?

 

I have never changed the transfer case or front/rear diff fluid. The manual states to do the following at 150k miles:
-change transfer case fluid
-change front axle lubricant
-change rear axle fluid (DANA axles not using synthetic)

I just wanted a sanity check from you other fellas to see if this is inline with what everyone else is doing. Also, do our axles use the synthetic fluid?....

 

You should start a signiture that has all the info about your truck(s)

Any fluid will be sadisfactory or better. It hase to do with opinon and price for stadard to other stadard oils and syn to other syn oils.

 

I changed mine at 50k miles - at least the transfer case and rear differential. I am late on the front axle.

 

Jaybird.....take a look at the Super Duty forum's tech folder. All of the questions about fluids and change intervals are answered in there.

 

Go ahead and change all 3. I think the diffs take syn, not sure. I have amsoil in mine. It is much quieter when im in 4X4.
I did not do any testing for temps or mpg, I did it for the benefit of upgrading to upper quality synthetics.

 

When you drain the case and rear diff, have the front of the truck higher than the rear so you can get more fluid out. not just an inch or 2, more like 5-12 inches, or higher if you want. You dont have to do this, its just some helpful info

And for the front diff have the rear higher than the front.

 

Do you recommend changing all 3 every 50k miles? Also, why does Ford recommend such long intervals? No big deal, this is something that i probably should've been doing every 50k, at least for the reassurance. Thanks for the input.

 

Mainly I just am conservative. However, I do a bit of driving through mud and water and just felt it was better not to wait longer than 50k.

 

How much does a rebuild on the transfer case cost?
How much to change the fluid?
Fluids are cheap and easy.

 

No. 1 issue is do you actually use the vehicle "off road".

If you ever have it off road, where water can reach even the bottom of the "pumpkin" or where water reach wheel bearing height (even briefly) there are a wholly different set of rules.

In essence, for those conditions:

It is possible for the axle / transfer case to have built a vacuum in this manner.

Hot (from use) axle / transfer case runs into deep cold water.

Rapid cooling shrinks the air inside, creating a negative pressure.

If at that moment, the "vent" on top of the axle, etc. are not flowing freely, what happens next...

Water gets literally vacuumed into the axle via whatever places possible --- anywhere from the bearings (right through the seals), to holes (maybe from rust) or cracks in the differential cover / seals that are too high to leak oil, but leak nevertheless if submerged.

Ditto for U-joints, and any lubed joint in the front end, suspension.

That is why, when you get a flood damaged vehicle (or even one that is driven in a flood zone), often the bearings / axles are water damaged.

That is true even if all the owner did is to drive through not quite axle deep water.

If you are lucky, water penetration is only to the outer wheel bearings -- $$$.

If you are not so lucky, water is in the axle / transfer cases...

You can answer that question for yourself as to what a few quarts of water will do in there if left unattended over time.


Here is what serious off roaders do:

Once they do a run where the axle might be partially submerged, the wheels are taken off and the bearings inspected for signs of water ingress.

If there are, remove bearings, clean completely, repack, and also drain the axle / transfer cases.

Do same with greased joints. When you inject new grease, the old grease comes out -- it can be inspected for the telltale sign of water.

The real pros that do off road have a special vent plumbed from the "pumpkin" to an air filter located much higher up to prevent water entering from the J tube on top of the axle.



Now, for on road.

Generally, every year, pull a small sample of oil by just removing the fill plug.

Look at the color, etc.

Do you see metal particles?

Dirt?

Signs of water?

Then change it.

Or do the change at say, every 50,000 miles just to be sure.


Definitely do the inspection immediately after if you ever ford water.

 

When you look at the Ford maintenance schedule, make sure you look at the section for "Special Operating Conditions". Chances are that those will apply to you, even if it does not seem very severe or special.

Trailer or camper?
Frequent idling or low speeds?
Dusty conditions?
Off-road?
Bio-fuel?

If none of those apply to you, I'm not sure why you are driving a truck.

For the transfer case for example, normal interval is 150k miles. Special Operating Conditions is 60k miles. Same kind of thing with the differentials.

I just changed my TC at about 68k miles. The old fluid looked like purple grape juice. Keep in mind it is ATF which should have been a nice light pink. In my opinion I was past due for the change.

On the other hand, my differential oils looked great. Changed the rear anyway, left the front as is.

 

I changed all my fluids at 70K after reading some of the discussions on here.
When I drained out ther rear Diff fluid it was like chocolate milk...definitely needed to be changed. I also took the opportunity to upgrade the rear diff cover to the '08 ribbed aluminum version to help in cooling.

In the severe service section it says to change it more often if you've EVER had the diff wet like going through a big puddle or launching a boat. i.e. if you've ever driven your truck.

The transfer case and front diff looked fine but i changed them anyway.

 

Thanks fellas. I'll be changing the rear/front diffs and transfer case fluids as soon as possible. Also if someone could post a link where I can find fluid type, capacity, and procedure for changing that would be very helpful. I looked in the TECH folder and didn't find many details on this. THANKS for the input. It would've been nice to have found this forum a couple years ago.