I am always a big believer in changing rear differential fluid. I just bought a factory service manual and honestly i think it is horrible compared to others i have for other cars. Anyway, Ford calls for the rear diff fluid to be changed at 60k miles with regular duty. I just hit 60k, and my truck falls close to severe duty service. However! after all this searching, it appears the rear diff on an 08 F450 is a Dana S110. There is no easy way to drain it, because it looks like i would need to disconnect the actual propeller shaft to do so because the rear end is sealed. However! after going on the Dana website, i saw this PDF, and it says that the S110 diff does not need maintenance for 250k miles? I have no idea if this is true or not, i cannot confirm this from any source, so any help is appreciated. I just cannot find any help on this, and the factory service manual is not helping either.

here is a link to the pdf file from the Dana site http://www2.dana.com/pdf/AXSL-0052.pdf

 

is there a way to at least check the level and add if necessary?

What about sucking the fluid out from there and then replace with new?

 

The beautiful Dana110 axle uses a third member and is a solid structure without the removable rear cover. I will be changing out the fluid soon(and boy does it contain a lot of oil). The way I will go about it is this: Take the truck out for a long drive to heat up the thick oil, Park it on a level surface, remove the fill plug and insert the tube from my suction pump(I have a oil removal vacuum contraption that I use to suck the oil out of the boat engines) and suck the oil out. I will then measure it to see how close to the axle's capacity I am able to remove. Even though it is best to have the oil as warm as possible you do need to let the truck sit for a time to allow the oil that has traveled out the axle tubes to migrate back to the pumpkin. My Dana110 is equipped with the limited slip unit so I need to find out how much/what type of friction modifier I need to add to the refill. I would rather be able to remove the rear cover and wipe the innerds clean to check for metal shavings/chunks but that is not possible with the 110. I only have 35,000 miles on the truck but it is now 4 years old so I will do it soon.

 

Well, I am sure the level is fine. I am trying to find not only the correct way to change the fluid, but how often is it REALLY suppose to be changed? I cannot find this anywhere!!

Does anyone know what axle the F350 DRW comes with?

 

I suppose that is not a bad way to do it. Its just, I would love to find out the real way they want you to do it, and most importanty, WHEN? it seems Ford is lacking LOTS of info on this axle, becuase even the factory service manual does not mention the fact that is is an LSD, and does not list what to add to it when filling. However, they do mention a part number for friction modifier for the few other diffs listed.

 

Odds are it's a D80.

 

There's mfg. specs, and then there's Fords specs. Dana/Spicer says the axle is good for 14K lbs, yet Ford rates it at 9500 in your F450 application. I'm sure the 60K interval they recommend comes from a similar train of thought. After all, they are the ones on the hook for warranty service if something fails, not Dana.

I'm not sure what you mean about a propeller shaft and the rear end being sealed. Driveshaft? Anyway, if you really want to get in there and clean I would imagine all you need to do is disconnect the driveshaft, pull the axle shafts out a bit, unbolt the center section and drop it out. I'm not 100% certain on this since I've never pulled mine, but it's a full float and the center section setup seems very much like a Ford 9". If this is the case then pulling it out should not be that big a deal. Axles are pretty easy to pull, as is the driveshaft. Unless there are surprises connect to the removal of the center section itself, the rest shouldn't add more than 30 minutes total to the whole job.

 

I would not be so sure about trusting the Ford factory service manual, have you seen it? It is a joke to me.. In the scheduled maintenance area they are SOMEHOW cover oil changes intervals on a Milain, Fusion and Focus etc... IT IS NOT EVEN SPECIFIC ON THE SUPER DUTY! I never seen such a service manual in my life, especially for the size of the 2 books and the price I paid. The 60K miles they ask for is VERY generic, and does not specify which application. Which is why I am seeking REAL answers.



As far as propeller shaft, you may call it a drive shaft, when dealing with RWD cars it is referred to as the center is the differential, then the 2 connections on each side turning the wheels are the driveshafts, and what is spinning the differential is the propeller shaft. In this case you can call if a driveshaft as it seems the terminology is different with trucks for some reason. I work on race cars all day, not trucks, so it is a little different.



Anyway, I can open the diff, all i would need to do is disconnect the drivershaft/propeller shaft then unbolt the cover. The entire assembly pretty much comes out with the cover its self. I would prefer NOT to have to disconnect the driveshaft/propeller shaft, but it seems like the only way, unless you want to suck it out like stated above. At the moment, I am trying to find out a real scheduled maintenance requirement for this particular diff, and i cannot seem to do so. The feeling I am getting from the Ford factory service manual is definitely to generic and not specific enough to be sure that this needs to be changed at 60k. I really just do not know where else to look for answers.

 

I don't know about race cars, but I have never EVER heard "what turns the wheels" called drive shafts. They are axle shafts, whether in a car or a truck. Axle shafts in an axle housing, which contains a differential, center section, third member, pig, take your pick. They all get used and some are more sensible than others.

Likewise on the propellor shaft. Mention that to most folks and they are going to look at you like you're from Mars, or England maybe.

While your terminolgy may be in use somewhere, and technically valid, it is far far from common in useage. At least in this country, and in non race car crowds.

I didn't say anything about trusting Fords manual, I only gave you a potential explanation as to why the difference between their recommended interval and the actual mfgrs recommended interval.

I'm guessing there are few people that change diff fluid at 60k. Shoot, I'd wager most people never do it period during their ownership.

 

Early on in my '09, there was a shudder on takeoff under load--I was sure it was the driveshaft angle but local Ford tech said it was fluid. It was not a warranty item even under the 3/36 bumper-to-bumper. Had it done and shudder was gone and has not reappeared at 77k miles. Cost about $400 and there was 'double' the recommended FM added. They suck it out as mentioned above.
Joe

 

Please do not feel the need to educate me on proper terminology. I am fully aware on what is called what on vehicles. I been working on cars all my life and am factory trained on Mercedes, Porsche and Ferrari. I said I DO NOT work on trucks, never did, I just do simple maintenance on mine. So if things refer differently to trucks, then I do not know what I am talking about!

However, the PROPER terminology Mercedes, Porsche and Ferrari uses is what I been taught to use. That is what it is covered in their service manuals too. I just looked in my house for a service manual, and all I can find is a Honda S2000 service manual, I opened it up, and guess what? Honda must be from mars or England too!!! Because they use the same terminology, Mercedes, Porsche and Ferrari does. Here are scanned images from the service manual so you can see for you self. Again, trucks with solid axle's, I do not know if this relates to.

 

Thanks. Wow $400? that is pricey!

 

Time, syn fluid and double dose of friction modifier...what can I say? But it stopped the shudder.
Joe

 

Yes, I suppose so, plus it holds a lot of fluid.

 

And please don't feel the need to go getting all excited. I never said you were wrong, if you'll reread I said your terminology may be technically valid, and it is, but that most people in this country would be confused, and I stand by that whether talking trucks OR cars. Shoot, search this site and I wager you wouldn't find more than a handful of propeller shafts in the whole place. Could be wrong though, wouldn't be the first time.


I may not be classically trained, but I've been wrenching on junk more than a day or two. Friends?