Whoooooops... My bad....... must be the time..

With my savage, i do put .2 mm thick spring metall behind the spiders.. Try it.. They engage a bit too much, but after they ran in, it results in a very strong diff (the spiders don't eat their way thru the cup that way (works with both aluminum and plastic cups)

I use shims behind the ringgear/bearing and the input pinion. (it takes some time, but it works like a charm...)

thanks alot for the help

Off topic, but FLM is including a modified spider cross pin in the diff cups now, to address the "needs slight modification" issue.
For the Revo diffs, I have only tried the Maximizer diff cups so far. I will try the 3racing cups in the near future, and FLM is making some diff cups with 3mm screws attaching the ring gear (stronger than the 2.5mm stockers, and the screws are easier to come by). Serum described shimming as I would have. As tight as possible while still being smooth. This applies to building any diff.

Good to know thanks

Okay Mike, good to know, FLM now includes the shaft!

This may also be off topic, but on my Maximizer cups I had to modify the yoke of one driveshaft a little. You had the same, Mike?

I'm looking forward to the 3Racing stuff.

You mean the shaft didn't fit thru the hole?

Yes, if you mean this small shaft with the thread that goes thru the hole in the output shaft of the diff.
Just by one mm or so. I thought I mentioned this, but have checked and found nothing. Possibly I mentioned it in a conversation or pm.

I didn't make any mods on my Maximizer diff. It fit right in fine and everything bolted up fine.

Hmm, the cup itself was a perfect fit. But on one side the output pinion shaft was not sticking out enough. Was reproduceable, and I checked against the stockers. Strange!

I used the stock driveshafts on mine. I had no such issue. ;)

Stock driveshaft here, too. Issues on both diffs, equally. Had a really close look, no mistake on my side, I believe. Both bearings were properly in place, but one output shaft was not long enough. Implies either a different geometry of the cup, or a horrible assembling job. I dunno.

Hey RC-M Mike, On page 3 of the revo hopups the diff cups for $15.50 are the 3Racing cups aren't they

Yes, they are. And the 3R external diff cases are on page 2. (they cost less than 30 bucks, wow)

Yes, they are the 3Racing cups and cases. I am working on getting many more 3racing items in stock(as soon as they come in stock from my distributor).

Thanks. I will be making an order soon