Is it toast?

[dashhho]

Well I am pretty ticked but maybe I am rushing to conclusions a bit. I just did a ~2000 mile trek across the country in my '05 B4000 4WD. I went to pull the plastic flaps out of the wheel well today to see where the 02 senors were and I seen a bunch of oil thrown around the the lower control arm and where the CV connects to the diff (on the drivers side). Well I checked the oil in the front diff and it is pretty damn low, I'm guessing the axle seal must have gone sometime and I am sure the heatwave did not help the situation...sucks I did not notice it and put on so many miles driving across the country in 4 days.

What are your bets? Is my front diff toasted? It is not making any offensive noises...just yet. I think it groans a tad bit when I slow down at very slow speeds though. My first thought is to dump the oil (check for shavings) and refill. Drive it for a few days and dump the oil again (check for shavings again) and see what happens. My thought was best case is I put a bunch of wear on it but can still get a bit of life out of it before having to rebuild. Thoughts?

 

[Dirtman]

My first thought is to dump the oil (check for shavings) and refill. Drive it for a few days and dump the oil again (check for shavings again) and see what happens.

Do this. It's probably fine...

 

[dashhho]

Do this. It's probably fine...

Thanks Dirtman. Fingers crossed!

 

[sgtsandman]

I’m with Dirman. If it isn’t making noise and there isn’t any metal shavings, it’s probably good. Check the axle vent and vent hose to make sure it isn’t plugged. If it’s plugged, that may be why you were spewing oil. There was no where for the axle to relive air pressure when it warmed up. Or the seal is bad. Maybe both.

 

[dashhho]

I don't own a pump to pull out the fluid so I just filled it up. It took about 600ml to fill, I believe my manual said it takes 1.7l so it still had oil in it. I'm thinking I will degrease and drive it to find the leak and then take off the cover and dump the fluid when I go to fix the leak.

 

[sgtsandman]

I would at least look at the vent and vent hose then. From what I remember, The axle side isn't that bad to get at. I never found the top side of the vent but I was busy swearing at the truck while doing a slave cylinder change and where the top of the hose was, wasn't a very high priority. Run some wire through the hose and make sure it's connected to the axle housing and that the vent in the axle housing isn't plugged.

 

[dashhho]

Sgt I think you nailed it. I had no idea that is what the line fastened near the top of the shock is for. Why would they put it there? I tore the plastic shield on that side so it is totally exposed to any dirt or mud that can get throw there.

I will clean it out and see if that does it. Itbwas definitely puking oil through the vent tube.

 

[dashhho]

Drove it for a bit today and its not pissing oil anywhere. It did make a bit of noise at the start but did quite down a bit after I drove it around the block, im sure lots of stuff was lacking lubrication. If it doesnt recover how hard is it to drop the front diff and rebuild that sucker? The access is horrible with it in the truck so I am hoping it is easy to drop the diff and work on it haha.

 

[sgtsandman]

Pull the CV axles out, drop the front drive shaft, and I think there are three bolts that holds the housing in place. A transmission jack to raise and lower it would be helpful. While you are at it, you might want to look into either getting a drain bung welded onto the cover (if there is enough room) or get a hole drilled and tapped for a plug on the bottom of the differential housing. I plan on doing one or the other when it comes time to drop mine for a fluid change. Removing the cover with the axle installed is impossible and making sure you have a good, clean surface to seal it back on is tricky. I got lucky on my ex girlfriend's Explorer Sport. It didn't leak after I did the job.

 

[Roert42]

It’s not that hard to pull the front diff, I’ve never rebuilt one though. Shouldn’t be any worse then most others though.

I tried welding a bung on the diff cover when I had mine out to change the oil, I got it all back together and there is not enough clearance to get the bolt out. I hate how tight it is. Putting a hole in the bottom of the housing, with a npt plug would probably work better anyway.

 

[sgtsandman]

It’s not that hard to pull the front diff, I’ve never rebuilt one though. Shouldn’t be any worse then most others though.

I tried welding a bung on the diff cover when I had mine out to change the oil, I got it all back together and there is not enough clearance to get the bolt out. I hate how tight it is. Putting a hole in the bottom of the housing, with a npt plug would probably work better anyway.

I was afraid of that but I'm not much of a fan of putting a drain plug on the bottom of the diff where it can hit something. I'll just have to make sure I get one that is a recessed square or torx drive so there is less stuff poking out to hit something.

 

[Roert42]

I was afraid of that but I'm not much of a fan of putting a drain plug on the bottom of the diff where it can hit something. I'll just have to make sure I get one that is a recessed square or torx drive so there is less stuff poking out to hit something.

I was thinking something like this.

 

[09fx4guy]

I dropped the axle on my 09 when I installed the Torsen, and it did not take that long, maybe a full day if you take your time with disassembly, checking it, and reassembly. I think you will need new axle bolts, they may be single use TTY bolts. Even still, I think it was about 15 bucks for all three, so the peace of mind was worth it to me. You would probably have the peace of mind after checking the condition of it.

I may take mine out again to change the fluid and check how the Torsen has worn. Regarding the drain plug, I may actually do the same thing to the front axle on mine. I have always been a bit leery of compromising the housing by drilling it, but I think if the plug is small enough, it should be ok. It will make fluid changes a lot easier.

 

[scotts90ranger]

Diff's need oil? The one in my Explorer is wet on the outside, so it must be fine... Conveniently I don't care about it as it'll be junk (the diff) soon anyway hopefully doing axle swat stuff... if you were close I'd offer parts off my parts Mountaineer...

 

[dashhho]

Thanks all for the good ideas. I am def going to try and get something on that front diff to drain it!

I've done some searching around on the gear oil for these suckers. It seems 75W-140 synthetic gear oil okay in both front and rears. The royal purple I found says it has the limited slip friction modifier already in it. I read some people say to add a tad more modifier in the rear axle? Has this been proven or is personal preference?