96 4x4 disengage issue - front differential low fluid?

[designerguy]

When engaged in 4-high, the engine RPM is higher, engine runs as if it's in a lower gear and it takes forever to shift out. A sharp left turn seems to help. I think it may have a slow leak and pehaps now the fluid is low. Would my symotoms be appropriate for low fluid?

If so, how can I fill the differential. Is there a filler hole? What type of fluid? Thanks!

[elwesso]

There is a plug you take out of the transfer case and diff. For the diff, you use GL-5 fluid.... you take the filler nut out and use a hand pump to fill it up until fluid comes overflows