Need help from other Expy owners that have changed their own rear Diff oil. How did you do it? I am trying to do mine, but the track bar is in the way and my compressor took a dump so i can not get the bolts off it. I have put the rear on ramps and the track bar is right in front of the cover. It does not look possible to remove the cover with the bar there. So did ya'll remove the bar, or is there something I am missing here?

 

I did my 99 and the track was not a problem just use a swivel socket to get around it
in a few places the cover slides down and did not need a lot of room to pop off, hardest this is to refill it.
bruce

 

Where your wheels on ramps or where they hanging?

 

is this a pre 03 expy?

 

yes, a 99 w/ 5.4

 

I have an oil extractor I use for changing the oil in my boat and used that. I drove around for a while to get the diff lube up to a decent temp then stuck the oil hose in through the fill plug. With a little effort it made it to the bottom of the diff and cleaned it right out.

This is the one I have:
http://www.boatus-store.com/webapp/w...roductId=10677

 

Did my 00 expy sitting right on the ground, used a universal on some of the bolts but the bar was not in the way, cover slid down and right off, used blue rtv when I put it back on as there is not a real gasket and fille dit with 3 qts 75-140 synthetic and 2 ozs of amzoil anti chatter for the clutch..

 

I was reading your post and became a little confused. I put some gear oil in each of my differentials, but then the shop told me to add some sort of anti-slippage oil or something like that. Doesn't it matter what ratio you have? What does that anti-chutter do for you? Since I have done this I have found that when I am not moving, just idle forward with a little gas, turn as sharp as I can it feels like my all wheel drive binds up, or something, the tires will chirp a little as well. Any help is appreciated because I would like to change the oils again and do it right.

 

Gear ratio does not matter. What they are talking about is the friction modifier that Ford sells. It is for Limited Slip diff's only. When you pulled the rear cover off, you should have had two tags that were bolted to it. One of these tags tells you if it is LS or not. The friction modifier allows the rear to "slip" some so you do not get that binding feeling you are speaking of.

If I read your post correctly, you changed the rear fluid but did NOT add any FM? If this is correct, just go to Ford, get some FM and add it through the top ABS sensor. (On top of the Diff is the ABS sensor, I think it is a 10mm bolt to remove it, you can add fluid through that hole.) I would pull the side plug and try to drain / soak up some fluid. You can do this by pushing the tip of a rag through the side fill hole to soak up some of the fluid. Then close it up and add the FM through the top hole. You will need to then go drive some Figure 8's to properly mix it from side to side (3-4 Fig 8's will be good). I would not worry about draining and refilling the diff, just soak some oil up and add the FM through the top. The front does not get FM (you have 4wd??).

 

Yes, it is 4wd. Does the front get teh FM as well, or does it have a tag. I think I might just replace both oils, I don't remember it being expensive and it would let me sleep better- smile. I think it was a strange weight that I put in as well, but can't remember. So, considering the feel of binding, do you think it has caused damage?

 

I have the same thing happening, the grabbing of the clutches, and it really only recently started to happen, like right after I just had the axle seal replaced at the dealer in June 2005. I looked at the service receipt and it shows that they put in the synth fluid as required and also the LS additive. Yet it still grabs. If I assume that they did put in the LS additive as they charged me for, do you still think it would be ok to withdraw some fluid and add another couple of ounces to the fluid as you suggest? In other words, if the rear diff fluid already has LS additive in it, will it hurt the diff if I nominally increase the percentage of LS additive by adding more? How bad will it hurt the diff if the clutches have been grabbing like this for several months? Last week for example, I got under the truck and unscrewed the diff fill plug, and the level was fine, but when I looked at the plug itself, it seemed to have heavy gray 'clay-like' stuff more or less baked onto the inside face of the plug. I scraped it off, rechecked the level (and the fluid seemed clear enough at the end of my finger as I checked it), and reinstalled the plug. But, now I am concerned that there may be some serious wear going on in there. I will try adding the LS additive as you say. Just wondering what you think of all this. Your opinion and experience are appreciated.

 

no the front does not get the FM. The weight is 75-140 for the rear, I have no idea about the front.

edit. BTW, the FM stinks to high hell and will ruin anything it touches b/c of the smell. My advise would be to use clothes that you do not mind trashing. I would also add it through the top sensor hole or put it in a bottle of gear lube if you plan to redo the whole thing.

 

All honesty, I do not know. Adding too much FM can be bad, I do not know wat too much is though, just that too much will allow the clutches to slip more than necessary thus wearing them out faster. You might want to bring this topic to light as a new post and see if others can provide more advise. To me it sounds like the clutches are toast, but you will probably get a better response by making this a new post.

 

its a safe bet that by now those clutches in your diff are ruinned. it does not a take long for them to go if the friction modifier is not in there.

 

I had the same issue on my 99 e.b. expy.... the dealer told me that the rear clutch pack was no good and it would cost like $ 800.00 to fix... took the truck home...
read diff cover off ... clean the rear end from all dirty oil... i put royal purple synthetic oil plus the friction modifier and the binding went away .. now the truck is gone but I was able to put 15k miles w/out any problem.. my 03 has a similar issue but it has an IRS rear and it will need the change as well.. I am just concern because it has no miles 30k.
My 2 cents !!