noise 92 Rodeo

I have a whinning sound comming from the rearend I think. I replaced the carrier bearing and the pinion bearings but still the same noise. Its more noticable at about 45 to 55 mph when Im just cruising with no tenshion on the rearend. Does anyone have any ideas.

Have you checked level & condition of fluid in your rear differential?

Have you checked level & condition of fluid in your rear differential?

Yes I put new fluid in when I changed the pinion bearrings. I used 80 90 gear oil.