i've been running the same diff in my erbe now for a year roughly. never faultered until the other day. i take it apart carefully spacing all the parts out as i go on a large towel. the spider gear output shaft on the cup side had the shaft with gear on the end, then the little blue seal, and then theres supposed to be a shim. well in my diff there was no shim at all and traxxas are telling me it should have been there. i know for certain it wasnt there, i never took apart this particular diff before so it must have been missing from the factory. i have 2 separate full traxxas diffs on standby that were pulled from a new truck so now it looks like i have to take them apart and see if they've been assembled properly as well, and buy some more oil to reassemble! anyone else have this problem or am i on my own? i love my erbe but this is frustrating!!