So i'm running the stock differentials that came with my 3906, And I have since put a brushless system in it. For the most part, the drive-train holds up great but i've been messing up differentials on 4s when i beat it hard enough. I was wondering if the diffs/diff cups, in the... 3908 is it? Are any stronger than the 3906's. Would it be a better investment to go aluminum cups or do you think the brushless diffs will hold up?
I cannot comment on the specific differences between 3906 & 3908 diffs, but I have the 3908 and am running 6s and have not had any diff issues.
Always get a 2nd Opinion!
From what I understand that the diffs for the 3905, 03 and 08 are the same. I've read that they are much stronger than the stock diff in the 3906. Lots of guys shim the newer diffs to make the fit tighter and in turn make them last longer.
Another popular option is to upgrade the diffs to a 1/8 scale diff like what FLM offers. Other mod the LST diffs to fit the Maxx and really enjoy it.
Just remember that if you go to a 1/8 scale diff you may want to consider adjusting your spur/motor pinion gear(s).
Aluminum cups may help. Are you cracking the plastic cups or are you striping spider gears? Seems to me that a lot of diff failures are at the point where the input pinion and the ring gear mesh… or rather, don't mesh.
The first time I messed one up, I had messed up the cup, but the gears seemed fine. I broke something the other day but I havent had the time to take the truck apart so ill have to get back to you. Thanks for all the help guys!
Would you go flip my truck back over??