Noisy hum on my '00...is it the differential?

Hey. Here are my boys. My 08 and 00. I actually bought the 08 first. Loved it so much, I bought my son an 00 to learn in. Mods are mostly electrical. Both have inverters for 110 AC power. A breaker box was installed of course.

The 08 has a second battery installed in the left rear of the engine compartment with a power disconnect switch installed in the cockpit. 5000 watts are available to run most anything I want, but its mostly for a small fridge when we travel. If we lose power in the house, I can keep most of the house going with my truck. I installed a shelf in the rear ceiling to hold the inverter and clothing and stuff. A 4 gauge wire runs from the second battery to the inverter through the floor and wall. A front receiver hitch is installed also, although I haven't come up with the light/winch combo yet that I want to install on it.

The 00 needed some work. I did most of the minor stuff; Radiator, starter, cats & O2's, fluids. It just got rear shocks, and front brake pads with rotors, and a windshield (be advised that rust under the window seals may be common place and should be addressed before it's too late). It's a great first vehicle for my son.

Now for my first question; the 00 needed rear axle seals replace. I had been driving it with no diff oil and now i get a noisy hum when I drive it. I'm thinking its the differential. ANY Thoughts?

 

i would make the assumption that if you had no oil in the diff the hum could be coming from it. could be a bearing, thats a typical sound that comes from a failing bearing

 

They told me that the bearings were okay, but the sound maybe coming from the spline area. It is not too loud, but just loud enough to be annoying. I will bring it to another mechanic, get another opinion. I'll keep you guys advised.

 

I had an identical situation and same symptoms. I replaced each rear wheel bearing and it didn't fix it. I'm getting some rust issues fixed in the shop and they're going to troubleshoot the humming as well. I'll let you know if I find anything out before you do. Their guess is maybe pinion bearing.

 

What was the finial result to fix the problem ?????

 

Mine was the pinion bearing in the rear diff. So I just searched for a donor with the same gear code on the vin sticker (which some say isn't a guarantee to match) and swapped that center chunk. Wasn't that bad to do.

 

I don't know what is causing the winning sound , but I checked the oil in the differential and it was.... almost empty " loose drain-plug" . Had it serviced, but , still hear the winning sound. I'm going to drive for awhile to see if it gets any worse !!!!! How did you determine the bearing failure ??????

 

Mine didn't go away when it was filled back up either. It was difficult! I tried putting little computer mics in different spots even n still never could be sure. The best luck I had, but most dangerous so be cautious if you do it, was putting the rear wheels up on stands n putting it in gear n listening from outside the car. I could kind of narrow down to the back at least. Is yours whining a higher pitch or humming lower

 

I have the winning higher pitch that is more prominent between 50-55 mph, and then seems to backs of slightly beyond that speed !!! Did the replacement of the bearing eliminate the hum ???? By the way, what did it cost to replace the pinion bearing ???? Thanks , Andy

 

I didn't just do the bearing, I found an entire differential to swap in that had good bearings cause I figured it was easier. I think I paid 200 for the used differential. And then the humming was completely gone

 

So, I just had the best experience and most horrendous experience. Bought a used 97, 5 speed, 4wd and loved every minute that I drove it. It had the same hum but everything was running strong, fluids looked good, and while it was annoying I managed to ignore it at highway speeds. Then it went kaboom and literally it blew itself apart. As far as I can figure, the rear diff bound up going 75, blew out the drive shaft, cracked the transmission, and blew the transfer case off of the engine. Needless to say, I am not quite happy with my most recent purchase and now glorified lawn ornament

 

Damn dude, at least you didn't wreck and get hurt. So needs all new drive train?

 

Thankfully I wasn't hurt. Did catch me by surprise when the linkage on the shifter snapped and the stick rapped my knuckles. It does need an entire drivetrain sadly. I bought it to learn how to tinker, fix, and teach myself how to install lifts before starting on my '12 Taco. I just didn't expect that repair so soon. I am not even set up to attempt to tackle it and a girlfriend saying that we should just take the loss and move on doesn't help

 

Ok I'll be that guy. How deep are you into it.

 

Thankfully, not much. About $2k total so I am happy about that.

 

As I'm sure you feel, I certainly wouldn't take it as a loss...just take your time and keep an eye out for each part you need and look up how to do each task online and youtube. Now instead of putting money into a lift, just get it back running n call it a day lol. Taco lift is prob different anyway, they might have leaf springs in the back. I don't know the condition of the rest of the vehicle but I'd say if you can replace/rebuild your broken parts for less than 2.5k you'd still be in good shape as far as what you could get back if you sold it.

 

Well if you can hunt down all the stuff in junk yards you might only be in it a total of 3500 if you do all the labor. All the stuff you broke it the big stuff so it is not hard to change out. Drive lines and what not are easy to find. I have a rear end if you are close to MO. It's out of an 02 so I would have to check the gears and see what they were again. I want to say 4:10's. That would get you started.

 

Sad news !!!!! What did the hum sound like before the the rear disengaged ??? I continue to have a winning sound and don't know if it's the rear or the bearings !!!!!

 

http://cloud.tapatalk.com/s/580817da9af9b/20141209_155322.mp4
This was a vid I took of mine trying to figure out what it was if you can see it. Ended up being the rear diff. pinion bearing most likely. Sorry it's short due to size limits. Sounded like I had big knobby tires lol

 

I'm starting to notice more and more ..... tire noise !!!! Could this very well be the....... beginning of the end !!!!