Deandome

My Feedback: (1)

I'm getting into a regular weekend run/break "something" schedule. Till now, it's been minor but bash-ending things. rear/center drive (got MIPs), spur replacement, battery came loose & flailed around (re-glued & fixed one wire).

Now it looks like something real...time for you Maxx MDs to render a diagnosis.

I lost rear drive altogether. Nothing in the CVDs/diffs...there's no power coming out of the TRANNY. The front is fine, and if you spin both front tires in the same direction, there's no reaction in the rear like you normally get. The rear isn't locked or anything, spin the tires & everyting sounds normal (no weird broken part noises/rattles)

I'm hoping someone can read those symptoms & tell me what parts/gears I'm likely to need BEFORE I operate on the tranny. I'm hoping/guessing it's the kinda problem where it can only be one thing wrong, that way I can have the part on hand before I get inside.

Thanks!!

Dean

R/C Madman

My Feedback: (1)

Are you 100% sure that there is no power to the rear output?? You may have broke the pin or it may have fallen out. The shaft that powers the front also powers the rear so, if the front is getting power it would have to be either (1) the shaft snapped at the back of the tranny but, that is unlikely as it rides on the bearrings and would more likely get bound up in the gears. (2) the set pin that holds your drive cup is broke or missing (3) the rear diff is bad and (4) the rear drive cups on your diff has a set pin broken or missing.

Dale Gribble

My Feedback: (4)

Interesting... My man above is right- the front/rear share the same solid steel shaft (PN 4994)... I would be VERY surprised if you broke that shaft. Not impossible, but unlikely. Easy check there though- Just hold the front driveshaft, and see if the rear spins by itself. If it doesn't- your internals are probably fine. If it does spin independent of the front- that shaft may have broken.

Not patronizing RC MadMan, but I agree on the driveshaft pins- either at the trans or the diff. You may have lost or sheared one and not even know it. Then the driveline would spin freely without engaging the transmission shaft. A quick check there will tell you if that is the case.

Finally, and my guess most likely- Your ring/pinion aren't meshing properly. Your rear tires will still spin properly because the differential is fine- but if the ring and/or pinion are shot, no power will get to the differential for distribution.

My guess-

75% likely ring/pinion problem
25% sheared/lost driveline pin

Deandome

My Feedback: (1)

The diff's fine...you spin one rear tire, the other moves in the opposite direction & when you spin both tires, the center drive bone spins. When I revved the engine, the rear center bone didn't spin at all!!

I'm thinking it has to be the set screws...the rear tranny cup is spinning 'round the output shaft. I coulda broken the shaft, but I imagine I'd hear a LOT of noise & the loose parts woulda destroyed the whole tranny.

I've always worried about those MIP cups/set screws...they always seem so loose within the threads. Should I use a different/THICKER threadlock? I use blue AE for pretty much everything...should I get some RED threadlock? Something else?

Dean

R/C Madman

My Feedback: (1)

If your drive shaft is moving when you turn the rear wheels by hand then it is forward of that and my first guess is the set pins or screws (which ever you have). You can use red thread lock but, remember it will be that much harder to get off if you need to take your truck apart.