Explorer 4x4 question

[dantheman68]

A few days ago I did a front differential fluid change on my explorer by siphoning and re adding fluid. It was raining pretty hard so I decided to test out the 4x4 high option at a low speed and when engaged there was a bit of groaning at less than 7mph. I didn't test at any higher speeds due to this. Is this normal?

 

[michael loibl]

Had you ever tried your four-wheel-drive prior to the fluid change?
On my truck I can definitely feel the slight vibration through the steering wheel when the front is engaged, but I think I can only feel it above 25 mph

 

[dantheman68]

No, I just bought the truck and didn't want to use it until I had slick pavement to try it on. I tested it when I looked at it but basically just to verify it would shift into high and low...

I'm hoping it's just because there was too much traction and the road wasn't as slippery as I thought. I guess I'll have to wait for snow.