Engine/Transmission (1998.5 - 2002) Front diff burping gear oil

[Dave MacArthur]

I was putting air in my right front tire tonight when I noticed some fluid on the upper control arm. It felt like oil. I went topside and looked to see where it could be coming from. I was afraid it would be the oil filter or turbo line. After looking around it looks like it is coming out of the front differential vent tube that is tied up to the inner fender. It was late and I was tired so I will check the level in the morning. My question is, what would cause it to burp fluid like that?



Thanks,



Dave

 

[LandShark]

I've had this happen several times. Usually when on a trip and making big changes in altitude and going off road.



Had the dealer look into it when under warranty and they cleaned or replaced the vent valve located on the end of the vent hose. Didn't help. Only happens every couple of years and only a few drops so I don't worry about it.



BTW: It hasn't happened since I changed to Mobile ! gear oil about 40,000 miles ago. (I doubt that gear oil type makes a difference, but you never know).



It's amazing the mess that a few drops of oil can make! Don't worry about it.

 

[johnrv4]

Ditto to what Landshark said. Both my '98 and '01 have both done it under the same conditions he described. I talked to my dealer, and he said it happens all the time, usually after an extended trip or altitude change (just like Landshark said). Maybe the lube gets aerated if the the spider gears happen to be in the right location and whip the oil around for an extended period of time? Then it might foam out of the vent. I changed my front diff. fluid over to Amsoil and haven't had a repeat, but I doubt it would make that much of a difference.

 

[Smills]

I just noticed fluid on my fender from the vent tube. Its funny how far a couple of drops of 90 weight go. Another thing that would help is if the front end didn't spin all the time IE locking hubs.



Landshark is the Mobile your using synthetic?

 

[LandShark]

wheelintoy: Yes, the Mobile 1 gear is synthetic and available at most auto parts stores. I also use Moblie 1 transmission fluid in the transfer case and (Mobile) Delvac 1 in the engine.

 

[csevers]

mine burps too but

only if I have been in 4low off road or not.

 

[mediccummin]

TSB for this

There is a TSB for this problem, had it done to my truck under warranty. They place a catch bottle at the end of the hose connected to the fender well. Can't remember the number off hand, I think it still does'nt address the problem of the oil coming out it just catches and returns it to the dif. At least it does'nt get all over the side of the truck now. Good luck, Check the Fritz web page for the TSB number...