Hoping someone here could shed some light on this one.
94' 4x4 Xtra-cab with 160K has a "moan/droan" noise under load condition particulary at highway speeds. Taking my foot off the gas it disappears. Sounds like it could be coming for the 5-speed tranny but hard to tell. Anyone here possibly offer up a good way to isolate the problem? Thanks to all in advance! - Dana

One option is to pull the rear drive shaft and put it in 4H with the front hubs locked and test drive in FWD. If the noise remains, you have eliminated the rear drive shaft and axle as a noise source. You might also drain and check the gear oil in the transmission. Look for metal debris in the oil.

I have a vague recollection of an earlier post on the forum that suggested worn transmission bearings and "brindling" on the transmission shaft (output, I think). If I recall correctly, the surface of the shaft gets a bit worn by the needle bearings so that it is no longer smooth and that causes noise.

Randy

was it like- "whhhooooooooooooooooo"?? key of G?

with mine it turned out to be the bearing at the rear differential. where the driveshaft meets the diff. output shaft i think.... or maybe input shaft.

take the rear shaft off and drive it in FWD to make sure.

Does it make the same noise in all gears? A lot of times if its the transmission the noise will be absent in 4th gear because that one is straight-through and puts very little load on most of the parts in the tranny.

As others have said, driving in front wheel drive is a good way to eliminate the rear drivetrain.

All good ideas ... I think isolating the front from the back sounds like the next step. I was under it this afternoon checking for the usuals ... Worn U-joints, bad rubber isolation mounts etc.
I did notice I can move the center bearing area shafting a good 1/2" when lifted with some force. Should this section move this much? The rubber doughnut looks sound withour any signs of deterioation & or cracks but could this still be bad/worn? Definately a "droaning" noise only under load, soon as I depress the clutch it goes right away.

Another slight annoyance... Anyone here figure out how to lube a squeaking clutch pedal? Nothing major but it sure gets to you after awhile. Noise is from the internal cab linkage area, are there plastic bushings in that pivot shaft? <img src="/forums/images/graemlins/confused.gif" alt="" />

Thanks!