Hi Jato gurus,
It's time to do some maintenance on my Jato, so I took out the diff, took it apart, cleaned it up and filled it with 4000wt silicone oil. Put everything back together, tighten up the screws and notice that 3 out of 4 screws have lost their thread and dont tighten, luckily I have a replacement diff set so I take it apart again and put the metal gears into the new diff, fill woth 4000wt oil again, make sure everything is correctly in place, gasket, blue o-rings etc and close. I tighten the screws until they are tight, check the diff runs smoothly and encounter a problem. It doesnt run smoothly at all, it is pretty hard to move and no where near smooth. Take it a apart again put it back together from scratch same thing happens, its not the rubber gasket, ive checked it multiple times and its sitting in its place correctly. How tight do you tighten your screws? I have noticed that if I leave them just before getting tight the diff runs smoothly but am worried they will unscrew themselves and start the diff leaking... any ideas? Screws ok if not really tight?

Did you use the small greyish plastic looking shim that goes between the rubber o ring and the inside of the diff? I had the same issue. When I rebuilt mines the first time with the traxxas metal drive shafts i used a shim on each side. When I rebuilt my diff for the second time I used a shim on either side and noticed it would not turn freely. I removed a shim and it worked fine spinning free. Dont leave the screws loose just remove a shim if you have too.

Its funny you should say that I have never removed any shims and today there werent any in there! Very strange.... I will further inspect tomorrow and let you know but this is weird...!

Strange indeed. They are a dark grey color made of a hard flexible plastic. It should be shim first, then the rubber O ring then the diff gear. Look carefully it has to be in there.

Ok you were right, didnt see them as they didnt come off when I took out the gears, they were just stuck to each gear and I didnt even notice. I put a different washer on, slightly thinner, seems a lot better. It may still not be 100% smooth but that could be me being paranoid, Im going to run it when I get my 17mm Hubs and will see how it goes! Thks for the help!

No problem man. If you need to you can completely remove a shim from one side to get a smoother operation.

If I do that it seems to rub.... gonna try it as so and worst case scenario take one shim out!