Drivers side front differential leak

First off where does the clunk come from, the front or center of the vehicle? It could be the transfer case/ front differential oil needs to be checked for leaks or low oil levels, or a universal joint worn out from transfer case to front differential.

drain the oil from the front diff and check for metal flakes
If you have flakes --diff problems
if the oil is clean then look else where --like cv joints or "U" joints in drive shafts

hello
the filter is located right above the front differential on drivers side on the engine if it is a 5.4. If it is a 4.6 then they put the filter in front of the drivers front wheelwell , adapter lines are ran from where the filter is on a 5.4
Good luck
Chris

it doesnt have to be lifted but is much easier if is. The axle will have to be unbolted from the cv shaft. there are 6 15mm bolts that hold the two together. once these are seperated, tie the cv shaft out of the way and tap on the axle to get it out of the differential housing. It should pop out because there is just a ring on the end of the splines that pops into a groove. this is all on the drivers side. The passenger side is a different story. seperating the cv shaft and the axle is the same but instead of popping the axle out, the housing has to be removed. It is also 15mm bolts 6 0r 7 of them . The 4 wheel drive actuator will also have to be disconnected and there are two nuts on the opposite end from the center section of the diff.

Get your truck up in a rack and take a look at the drive shaft, the differential, the u joints and the ball joints. Regards, joe

Check the axle boot. When they rip or crack they will sling grease around.

im not that familiar with hummers but it sounds like youve found the end of the transmission vent hose or possibly the front differential vent hose and they will have seepage of oil sometimes. however if its a constant oil drippage, then there could be a buildup of pressure inside tranny or rearend. if u follow the hose down to its beginning youll know if its the trans. or differential(rearend). it might be normal to see this fluid,or it could be too much fluid inside trany/rear.

I cannot see it, but I am guessing that you need to replace your axle seal. To do this,you have to pull your CV shaft out. Remove the tire, remove the caliper from the top of the rotor. Using a hammer on the back, remove the rotor. Take off the spindle (axle) nut, separate the axle (CV shaft) from the hub. Replace seal. It should pop right out. Good luck!

Remove tire, remove axle nut, pop ball joint off, remove clip, pull axle

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There is an adapter for the oil filter with 2 lines coming out of it above the drive shaft from the transfer case to the front differential. The O ring on these will go sometimes causing loss of oil. Also check the 2 lines for leaks and cracks.