Your rear diff is starting to strip. You may be able to save it by shimming, but if you're going to open it up anyway just get a new diff assembly off of eBay and make sure you shim before you put it back together. FYI. If you hear clicking when going forward your rear diff is stripped, if you hear clicks when going in reverse the front diff is stripped. Jimmie Neutron has a great how to on shimming diffs. I'll see if I can find it and post a link.
PS. Love the French Bulldog!
Edit here's Jimmies diff shimming how to. http://traxxas.com/forums/showthread...m+differential
I follow this like the gospel and my diffs have been going strong for well over a year!
Last edited by Maxximum Overdive; 01-25-2013 at 05:13 PM.
Yes i can also recommend you to shim your diff. My first diff was stripped like yours and i shimmed it, it was quite okay for a short while. But than I had to replace it. With this new Diff I drive for 9 month (3S, 2S speedruns and skatepark bashs)
Is it TRA7078?
Yes TRA 7078 is the correct diff assembly. Make sure you pick up some diff fluid cause usually they're empty from the factory and over time some of it leaks out no matter what you do. Stock diff fluid is 30k.
Good deal! I have some 50k and 100k for my 1:10 Slash 4x4 that I can use.
I expect the tutorial tells me what or if I need other parts?
Yep the link I posted above will tell you everything you need to know. You'll also need Associated 21141 shims to do the job.
Should 50k be good? If its 30k stock, it sure doesn't act like it.
Should I be looking at a center diff, too?
50k would work, it just won't diff out as easy but it will be fine. 50k is what I use and I like the way it reacts. The center diff is totally up to you. Some people swear by them and others can't stand them. The nice thing about the center diff is it takes a lot of the strain off of the driveline so you don't strip out diffs or pop your axels quite as easy. The bad is that the center diff will bleed the power off to the path of least resistance and with the mini summit that will be the front wheels most of the time since its a wheelie popping monster! This can be easily remedied by using a thicker diff fluid to stop the center diff from diffing out to much.
I'm pretty shocked the diff is failing so quickly. Is it prevalent in the front one, too?
I definitely like the spool/locker effect of heavy weight oils in diffs. The Summit seems so difficult to turn as is, I'll be interested to see how the 50k changes things in that regard.
Can I pretty much just drive it as is until the replacement is in and altered?
Ya the diffs are a weak point and its definitely recommended to shim them right out of the box on a brand new truck! The rear definitely goes more than the front. As long as you don't slam on the brakes at top speed a lot or do a bunch of back flips (I know it's awesome, but the front diff hates it!) you'll be good. Sure you can drive it untill the new diff arrives, it'll get progressively worse, but your replacing it so who cares. If you want to try and save the diff then I'd stop driving otherwise let her rip!
Edit: I'd shim the front diff too to be sure it doesn't strip for a long while.
Last edited by Maxximum Overdive; 01-25-2013 at 06:43 PM.
So am I good to shim the front even though it isn't new?
I'm going to try my LHS tomorrow, but I have a feeling I'll be ordering it all.
I shim right out of the box... run a few packs and then check it again.
Whatever it is I just said... I could be wrong.
Good deal. I'm already over complicating this in my head. I'll report back once I have the parts, make the adjustment and install it. This will certainly give me something to obsess about for the next few days.
After looking at the fix, it appears the problem is the bulkhead and not the diff. Is that correct? If that is the case, should I get a new bulkhead in the process or am I better off using the existing one since it should have less elasticity?
As long as the bulkhead isn't cracked you'll be fine to reuse it. You can pick up the whole bulkhead with the diff assembly brand new pretty cheap off of a ebay chop shop.