Another bad tranny - Granite BLX diff problems -- any upgrades?

[YZFR1]

My Xmas present Granite just blew its metal geared diff - totally freewheels now.

This was after just a handful of runs -- all 100% stock, and running OEM NiMH battery.

Truck is now getting shipped back to Arrma / Hobbico for inspection and repair, but I'm so disappointed.

There's no way this thing is going to last on Lipo power...and constant warranty repairs (assuming Hobbio keeps fixing things) isn't very efficient.

Anyone have a long term solution to the poorly engineered differentials in these 1/10 cars??

Is the HPI diff option still on the table ... I've read about it, but doesn't seem like we have a lot of first hand experience.

Thanks guys!

 

[ajdragon]

Hi

I get the feeling that the O-rings are too big or too thick, and this is why the washers in the diff gears are getting deformed. When I put the new O-rings and washers in my diff gear I noticed that the pin that went into the out drives was overly tight fitting, a little to tight for my liking. I'm thinking I might just see about getting slightly smaller O-rings to replace the stock ones to see how well that works out.

 

[Dustin Mustangs]

Just playing devils advocate here, but how tight was your slipper adjusted? With good traction and heavy throttle, could you hear it slipping with a little squeal?? My BLx tranny has been fine through countless 2s packs and a handful on 3s. I am even running the option spur which is roughly 5% steeper than stock. My slipper is set on the conservative side and I have to wonder if that is the difference maker. The way I see it, if it is a flawed design, wouldn't we all be having failures?

 

[YZFR1]

Good point Dustin -- slipper was set to "stock" setting per manual -- can't recall but something like 2 or 2-1/2 turns out from fully tightened...
Note that total combined run time on the truck was 40-45min since new...failure occurred on run #6...so it was still pretty new. Now if running a looser slipper contributes to better longevity, I'm all for it, but I'm waiting to hear back from Hobbico. Re: failures, ironically I ran into this thread after the fact: http://forum.goforit-rc.com/showthread.php?955-2013-1-10th-scale-differential-problems
Of course the data is skewed since people are way more likely to complain about a problem, vs. those who have had good luck, but I still read it all and learned a few things.