Differential oil level

[TJ Sport]

The rear end differential on my 2003 Sport Trac is slinging oil at the u-joint. I want to check the oil level and add oil if necessary, but there are no fill and level plugs on the differential. What's the best way to check the oil level and add oil?

 

[theluke19]

If memory serves me correct, there's a fill plug- and the proper level is up to the fill plug. You should be able to put the truck on a level surface, take out the fill plug, and reach in with your little finger and touch diff oil.

The orange tube is running into the fill plug on this picture.

 

[TJ Sport]

Thanks, Luke. I never thought to look at the front of the differential. I guess I'll have to crawl in a little further this time!

 

[theluke19]

I think the plug can be opened with a 1/2 drive ratchet or breaker bar

 

[swshawaii]

^ Good info and pic, but it's 3/8". Also check the axle vent hose, it's been known to blow out axle seals when plugged.

 

[koda2000]

I think the plug can be opened with a 1/2 drive ratchet or breaker bar

Pretty sure I've removed my fill plug with a 3/8" extension.

 

[TJ Sport]

Thanks, guys. I checked the plug today. It is 3/8" square and I had checked the vent. The vent doesn't have a hose on it though, so I bought one to put over the vent.