Thumping / popping while driving...wheel bearings?

[LeadHead]

The other day my camo love-machine started to get a little salty on me. Started doing this whole thumping deal when I go over, like...5 mph. The faster I go, the more it thumps. I cant really tell where it's coming from. But I can feel it in the floorboards and it seems like it's somewhere up front or under me. I was running some Super Swamper Thornbirds. So I put on some old Wranglers and it still does it! There didn't seem to be any play that would suggest wheel bearings.

Is it time for me to break down and take it to a mechanic for the first time?

The truck is a 1985 M1009. 10 bolt axles and lock-out hubs.

 

[crazy4offroad]

Auto trans? Full-time 4WD? Front driveshaft or axleshaft joints?

 

[LeadHead]

Auto trans? Full-time 4WD? Front driveshaft or axleshaft joints?

Sorry!

Auto trans. NP208 (part time with locking hubs).

 

[crazy4offroad]

Check the obvious, trans bellhousing bolts, transmission-transfer case bolts, front driveshaft, axleshaft u-joints, torque converter bolts. Put the truck in neutral and rev it while rolling a little and see if it is more relative to engine speed or vehicle speed.