Do I have a front diff problem?

I'm trying to chase down a vibration/growl that sounds like a wheel bearing in the front end but I'm having no luck.

When I'm driving down the road I get what sounds like a metal scraping noise, like a dust shield rubbing on a rotor or a bad/dry wheel bearing. I removed both my front dust shields so that eliminated that possibility. I recently had the rear drive shaft serviced and my carrier bearing replaced as well as a rear u-joint and the driveshaft was balanced. I just had new tires put on and changed out a front tie rod end that was bad.

The sound comes and goes, but it is there more often then not.

When I had my new tires put on, I had Kauffman tire check the wheel bearing, they said the bearing is quiet and they thought maybe something in the differential and told me to take it to a full service shop. So I went over to the dealership to have them look at it and after sitting around for 3 hours they charged me $150 and said that the wheel bearing "was the place to start". There is no play in the wheel bearing if a jack the truck up and grab the wheel at 12 and 6 to shake it. If I spin the wheel while its jacked up there is no noise from the bearing.

I'm wondering if I have a problem in my differential...and I don't really know much about the differentials so I'm going to ask some stupid questions here...but I gotta learn some how!

With the truck jacked up and the in 2WD, I can spin the front driveshaft by hand no problem. My 2 front tires spin by hand but they don't free spin. What I mean by that is if I grab the tire and spin it, let go and it wont continue to spin more than a half to full rotation at most. I pulled the brake pads out of the caliper so that I could be sure that the pistons in the caliper were all moving properly and it isn't the pads keeping the tire from spinning. Is it normal for the tires to not spin more than that?

Second...I'm pretty sure that my front u-joint is bad on the front drive shaft. There seems to be some play in it, but do I have a bigger problem based on this video? Is the sound coming from inside the diff just the normal sound of the gears moving? I haven't drained and refilled the diff yet because those plugs are a pain in the ass to get out!

https://youtu.be/LgvKZKHhyzQ

 

Does the problem go away in 4x4?

 

No it didn't change with the 4x4. I had initially thought needle bearing, but I'm not sure that is it since the sound doesn't seem to change with it in 4x4.

 

you said you haven't changed the fluids yet.. i would start there before digging straight into the diff...

Grab a clean floorpan (sparkly clean) and drain all of your differential fluid into it,
Next try and see if you can find any shavings.. Filings are OK and normal wear, but big chunks and we have an issue...

when you go to refill you front diff, try using Hyperlube it helps the oil stick to your gears better.. I use it in my Front and rear Diff, and Tranny.. Stuff Does wonders.

 

I'll change the fluids this weekend and see what comes out. I did the fluids last about 30,000 miles ago. I'll see what I find...

Does the play or noise in the video raise any flags that you can see? I feel like that front u-joint has gotta be bad to knock like that?

 

It’s possible it’s the U-joint..
The usual signs of a bad u-joint are
Vibrations,grinding and a clanking like sound. Has it ever been greased ?

 

I just had the whole driveshaft serviced at a reputable driveshaft shop, I can see where they greased everything up. That is kind of what has me stumped though, I feel like if that front joint was bad they would have caught it...so it makes me question whether the movement is normal...


I'm going to drain the diff either tonight or tomorrow and will post back with what I find.

 

Agreed, A shop is definitely gonna know more than i do whether that Ujoint is bad or not.
Another thing to do would be to put it in 4x4 and check the backlash and depth of your front pinion.
Jake.

 

Well, I started to change the front diff fluid but apparently I'm gonna have to wait...I cracked the fill plug and thought it was going to be a quick easy job only to find the drain plug is rounded. I had the dealership change my fluid about 30k maybe 35k ago and apparently they wrecked the plug and didn't bother to replace it. Gotta get someone to weld a nut on it.

I'm going to take the truck back to the driveshaft shop Monday morning and have them take a look at the front u-joint as well...unless someone else chimes in with input on the movement in the video...I can't seem to catch a break.