Well, while running my Slash 4x4 today it started making a grinding sound in the rear gear area after just a couple minutes of running it. After taking it apart I found that the rear diff bearing was busted and little ball bearings were all in my rear housing.I've only had my truck for about 3 weeks so I was pretty shocked to have this happen already. Has anyone experienced this problem and is the only thing I have to replace going to be the bearing? Part # 5120

It may have ruined your pinion and ring gear. Call Traxxas, tell them what happened and that you were just running the truck normal, and they will likely warranty it. The key is to call instead of E-mailing

Eric

When you say they will warranty it, does that mean they will just send me the replacement parts? 

I've heard of the slipper clutch bushing and bearing problem but that is a fairly easy fix. http://monster.traxxas.com/showthrea...slipper+clutch and http://monster.traxxas.com/showthrea...lipper+bearing

Since you've only had the truck 3 weeks you might call Traxxas and see if they will send you replacements. A quick search of the Traxxas 4x4 forum show others that are having bearing problems. Not necessarily the rear diff bearings.

Also, here is a video on how to clean rubber sealed bearings. http://www.youtube.com/watch?v=T_yhucQjFBg

I think calling Traxxas is a hit or miss. Lots have called and got things replaced but others get told its not covered. I would try first but if not then it's not a hard x anyways.
Good luck.

UNLESS YOU ARE GOING TO SAY YOU HAVE ONLY BEEN DRIVING IT NICE AND EASY AROUND YOUR YARD, I WOULD ADVISE TO KEEP THE "onlyhadit3 weeks, soiamsurpised" BIT OUT OF THE DISCUSSION. PEOPLE ARE NEVER AS EASY ON THEIR RCs AS THEY LIKE TO SAY. TEAR UP SOMETHING, BUY THE REPLACEMENT, FIX IT, AND MOVE ON.

Well I called the hobby shop that is about an hour and a half away from my house today and they said they would hold their last set of 5120 bearings for me till I'm there tomorrow.  I also called Traxxas and they were pretty cool about it and said they would have a set of bearings in the mail tomorrow.  They asked me if it damaged anything else, but as far as I can see everything else looks good.  I told them I would know more when I put it all back together.  What bearings do you guys use to upgrade to?  I know they have to make bearings for these things that are better than what comes with it.

Maybe this thread will help. http://monster.traxxas.com/showthread.php?t=520724