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Ok so I had my front axle seals replaced because one was leaking. I had them do them both because it is only a ½ hour more compared to 2.5 hours for one.
This is a 2003 Screw f-150 4x4
Anyways long story short I got my truck back and drove it for 3 days then I noticed the front axle was leaking again. The dealership has a 1 year 12K mile warranty on all the work done, so I take it back in. the mechanic looks at it and say crap the axle popped out for some reason. Not all the way just so it was not sealed. Well he took it all apart because they figured something happened with the C-clips that hold the axles. Later he call me back and say it has the wrong passenger side axle.

He tells me that this is why it was leaking in the first place. He shows me the driver’s side axle and it uses a C-clip to hold it in. It is flat with a little neck on it this is the correct one. Then he shows me the passenger side and it looks different. It is the style that does not use a C-clip. Splines go all the way to the end. We go look it up on the computer and all the Diver sides use a C-clip style one, but the passenger side can be a C-clip or the other depending on the Tag on the Diff. they look it all up and order the right one according to the tag.
Any thought on this. The mechanic said it must have been replaced with the wrong one by a previous owner, but why it looks like its from the factory and nothing els was replaced? I said it my be from the factory. We both thought all the fords used the kind that do not use C-clips. For some reason in 03 it may have changed. Info?

Anyways everything looked good no damage because they are the same axle other than how they are held in and it can’t come out it just won’t seal tight. The gears and all looked good has had oil on them the whole time so never got to low.

FYI I only had to pay for the axle $120 so not bad. All the labor was covered under the warranty.
Great guys at the dealership. Helped me out a lot on other things.