I checked my Front diff. fluid the other day and I thought it was low. I filled it up until it came out the plug. I have read that this was no the thing to do, and I overfilled it. I put a quart in it. Right after though it came right back out the passenger side axle tube. And for the next couple days while driving, I got a little bit out.

Did I overfill the housing, or do I have an axle seal bad? Thanks for any input given.

 

Sounds like the seal is bad. It's a bit of work to change. You more or less have to strip down the whole front end, to include pulling the ring gear and carrier out if you want to replace the driver's side seal (I would). It would be a good time to replace the ball joints or U joints if any of those parts are getting worn.

I have always filled up differentials until the oil starts coming of the fill hole.

 

I would take the vent off and make sure it isn't clogged. I have seen them clogged and push the fluid out the axel seal.

 

Thanks for the input, I read on post this morning, that you are supposed to only fill to 3/4" below the drain plug. But that is the first time I have ever heard of that before.

 

It's not the space shuttle man. Check the vent like stated above, fill it to the plug and go. If it still leaks out the axle end, replace the seals (left and right) and then go from there. I had a leaking seal on my rear end.....so says my wife....jk...and it was a simple fix for a shop to do. I'm a good mechanic but without a lift or enough time to the job, I figured I'd let someone else do it...

 

Get the fluid to the proper level and see if it stops. There are posts on this board that axle seals started leaking when filled too full (to the bottom of the fill hole), and stopped when the proper level was reached.

 

Fluid level doesn't matter. Filling it to the plug or 1/2" below, 3/4" below... The leak probably stops because oil isn't touching the seal anymore

Every Ford, Dana and Coporate axle I've worked on, got filled to the fill plug. The axle under my Jeep has the pinion clocked up pretty high and the fill plug is on the front of the axle... so it ends up holding about 5 quarts, vs ~3 stock. No issues.

Better to have more oil then not enough and burn a bearing up.

 

Why would the manufacturer have a spec on the fill level if it wasn't important? Makes no sense to list one if there wasn't a good reason. As I stated before, they can and will leak if they are over full, and often stop when the level is corrected.

 

Where are you getting your specs from, this is the first time I have ever heard of not filling it to the plug? I can find nothing in the service manual that says anything about filling it to 3/4" below the plug.

 

Engineers often don't use good reason when they design things. All my axle leaks have been caused by a plugged vent. Double check that before you drive on it, or you'll lose another seal.

 

It's in the owners manual in both of my trucks, under "Maintaining your vehicle". It states that in the Dana 60 front axle, the fluid level should be 0.25" below the fill hole, + or - 0.25" . On all rear axles the fluid should be 0.75" below the fill hole, + or - 0.25". On the 2003 and above, there is a fill line stamped on the cover, that is also below the fill hole.