Mojave Crunchy Moj EXB Diffs

[Grimbles]

So it looks like I cooked another diff on my Mojave EXB (this time front with LSD plates @ 20k oil weight). I'm going to try to take a video of what I find when I strip it down, and may convert this one to open too (will try running one at 30k first, but don't want to introduce more traction roll).

This was a brand new diff in a brand new diff case with brand new internals (I'd broken diff cups on the old one), it was silky smooth when it went in. It had had two 6s and one 8s pack through it, longish grass and some jumps but nothing out of the ordinary.

 

[BashingBrian]

Arrma tough..!!

 

[Grimbles]

Arrma tough..!!

I will do a short video when I disassemble to show what the contents are like!

 

[Jon NC RC]

I will do a short video when I disassemble to show what the contents are like!

Please do.....

 

[Sandracer_NL]

You Sir, do justice to your user title under your avatar.
Curious though what you’ll find when you open the diff…

 

[Grimbles]

1st video here, just demonstrating what it's like when these exb diffs go "crunchy". Reminder this was 1 bash session (3 packs), no big crashes.

 

[BashingBrian]

My guess is, melted diff plates

 

[jondilly1974]

My guess is, melted diff plates

I think the planetary gear teeth are broken and shards are stuck in the satellite gears.

 

[Grimbles]

The last one which went like this was the rear, and it had got so hot the inners of the diff had melted a bit! The rear is now fully open and this may be the solution for the front too, albeit I am going to persevere, not least because I built myself up two replacements a couple of weeks ago which are in perfect nick with 20k oil

 

[BashingBrian]

Do we get a prize for the correct answer..!!

 

[Grimbles]

Do we get a prize for the correct answer..!!

I mean... happy to post you the broken bits?!

 

[Grimbles]

Righto chaps! Here's a 10 min video of me p1ssing about with a moj exb diff. If this is all too boring, punchline is at about 7:10. Nobody won!

 

[L3phturn]

Righto chaps! Here's a 10 min video of me p1ssing about with a moj exb diff. If this is all too boring, punchline is at about 7:10. Nobody won!

Would you believe the thing that has lasted longest in my Notorious (which I overpowered with a 4092 motor ) is a piece of 2mm Allen key I cut off and used when I couldn’t get pins last fall?

 

[Grimbles]

Would you believe the thing that has lasted longest in my Notorious (which I overpowered with a 4092 motor ) is a piece of 2mm Allen key I cut off and used when I couldn’t get pins last fall?

What did you cut it with? Dremel?

 

[BashingBrian]

Awesome !!! well not awesome, but you know what I mean

Replace the pins with HSS drill bits they are much tougher..!! I use these ones eBay #361968921087 you'll want 2.5mm
Quite hard to cut them without the right tools, and also cheaper than the stock Arrma pins and in stock too.!! (not like the Arrma pins)

Edit: cut them with a Dremel with a cutting disc..
New on the left, stock on the right..

 

[Grimbles]

Awesome !!! well not awesome, but you know what I mean

Replace the pins with HSS drill bits they are much tougher..!! I use these ones eBay #361968921087 you'll want 2.5mm
Quite hard to cut them without the right tools, and also cheaper than the stock Arrma pins and in stock too.!! (not like the Arrma pins)

Edit: cut them with a Dremel with a cutting disc..
New on the left, stock on the right..

View attachment 152541

Ta

 

[L3phturn]

What did you cut it with? Dremel?

Yep, it did the trick.

 

[Burt37]

Righto chaps! Here's a 10 min video of me p1ssing about with a moj exb diff. If this is all too boring, punchline is at about 7:10. Nobody won!

Not sure if you miss it, but in the manual, it clearly states that you should use 37.5% brake for off road and 50% for on road...

My guess is that off road you get more grip with the OEM tyres than on road...

Not say that this was your problem, but in the video you did mention having the brake set to 50%...

 

[Grimbles]

Not sure if you miss it, but in the manual, it clearly states that you should use 37.5% brake for off road and 50% for on road...

My guess is that off road you get more grip with the OEM tyres than on road...

Not say that this was your problem, but in the video you did mention having the brake set to 50%...

Interesting - didn't notice this is the manual as, because it's an exb with my own electronics I didn't look at this. Have dropped brake on this one to 35% now anyway. Ran it last weekend pretty happily

 

[Burt37]

Interesting - didn't notice this is the manual as, because it's an exb with my own electronics I didn't look at this. Have dropped brake on this one to 35% now anyway. Ran it last weekend pretty happily

You are right. And I misspoken as well. It was not in the manual that I read those info but in the ESC manual from Spektrum...

Link HERE