Infraction Infraction center diff help

[Jagamov]

Hi all,

I was running my Infraction today and it started making a weird noise.

Upon inspection, I noticed grease near the main gear so I figured it was something in the center diff.

I took it apart and here is what I found. Can anyone explain maybe what caused this? The gears inside seem ok, like the teeth are ok, but what are those holes in the case?

Thanks in advance!

 

[332_RC]

It got too hot & melted the composite diff case. The holes are from the satellite gears & cross pins/tombstones. They wore a hole in the case. Been there with my Notorious.

 

[MrTitanium]

Mostly likely cause is lack of lubrication. Gears got hot and boom goes diff.

 

[fozzy71]

ARRMA Metal Diff Case, ARA220050

 

[332_RC]

And minimum 200k

 

[MrTitanium]

ARRMA Metal Diff Case, ARA220050

View attachment 381105

Although these are superb units (I run them in all my 6s rigs), the lack of lubrication will also wear these out. The amount of RPM that those gears turn is mind blowing.

 

[332_RC]

And the aluminum diff case doesn't reuse the side tombstones. Dissipating heat much better.

 

[Tex Koder]

Hi all,

I was running my Infraction today and it started making a weird noise.

Upon inspection, I noticed grease near the main gear so I figured it was something in the center diff.

I took it apart and here is what I found. Can anyone explain maybe what caused this? The gears inside seem ok, like the teeth are ok, but what are those holes in the case?

Thanks in advance!

View attachment 381100View attachment 381097

Toasted...

 

[fozzy71]

To prevent this from happening again, the best approach is to install a spool, like I did with my Infraction and my 2 Typhon street bashers. I only have center differentials in my FireTeam and 1 of my Typhons, both equipped with the bigger wheels. Any vehicle of mine with small street tires gets a spool. If all you do is drift and donuts, you probably won't like the spool though.

 

[Jagamov]

Mostly likely cause is lack of lubrication. Gears got hot and boom goes diff.

It seemed to be lubricated fairly well. Diff oil was sprayed all over the place, but yeah, could still have been low.

And minimum 200k

Is this the consensus on what weight I should refill it with? I just drift and do donuts and run it around the street.

And the aluminum diff case doesn't reuse the side tombstones. Dissipating heat much better.

That’s good. Cuz I think I lost a tombstone and the other 3 are welded in the case.

To prevent this from happening again, the best approach is to install a spool, like I did with my Infraction and my 2 Typhon street bashers. I only have center differentials in my FireTeam and 1 of my Typhons, both equipped with the bigger wheels. Any vehicle of mine with small street tires gets a spool. If all you do is drift and donuts, you probably won't like the spool though.

Thanks! I’ll stick with the diff I think. I pretty much drift and do donuts out in the street.

Second question:

I read in the manual and of course I don’t use the handbrake while it’s under power. However it’s very easy to lightly touch the rocker switch.

Could this have caused it?

Also, is there a quick way to reverse the 3rd channel? Might make more sense to have the handbrake activate with the top bottom, and if you accidentally hit the lower button, it just opens up more.

OR….should I just remove the handbrake all together? It’s fun to use it, but not a deal breaker if its gonna explode diffs.

Thanks everyone!

 

[RC Steve]

Those rubber O-rings that seal your diffs at each end wear out faster than you would think. When they do the truck will slowly convert to front wheel drive then the center diff case melts. Been there, done that, and with a Notorious.

 

[332_RC]

Is this the consensus on what weight I should refill it with? I just drift and do donuts and run it around the street.


That’s good. Cuz I think I lost a tombstone and the other 3 are welded in the case

200k is good. 100k stock. I have an Infraction 6s & I swapped to 200k center before I ever hooked a battery to it. Most of the searches & responses I got on this subject, 200k start. I run mine 50/200/20. Good for all around street bashing.

I haven't removed my handbrake. I only use it here & there. Makes powerslides cool. Then nail the throttle, 180s.

 

[Jagamov]

Those rubber O-rings that seal your diffs at each end wear out faster than you would think. When they do the truck will slowly convert to front wheel drive then the center diff case melts. Been there, done that, and with a Notorious.

Thanks for mentioning that. I didn't notice them on the teardown and when I first looked at the exploded view. I will get new ones of those too.

 

[fozzy71]

Thanks for mentioning that. I didn't notice them on the teardown and when I first looked at the exploded view. I will get new ones of those too.

I assume you know, but in case you don't: You can likely get a couple of the stock ones as complete take-offs from Jenny's for less than rebuild parts from Arrma and have a full spare for when the next one wears out.

https://jennysrc.com/search?type=product&q=46t+diff+arrma+6s

 

[Jagamov]

I assume you know, but in case you don't: You can likely get a couple of the stock ones as complete take-offs from Jenny's for less than rebuild parts from Arrma and have a full spare for when the next one wears out.

https://jennysrc.com/search?type=product&q=46t+diff+arrma+6s

View attachment 381237

Thanks! Yeah, I recently got familiar with Jenny's (I actually have some hubs on the way). It's a good idea for sure.

I'm going to rebuild this one with the aluminum diff case. Parts costs is actually very similar for what I need.

 

[morrjr71]

I was fully aware of the composite center diff case melting issue when I bought my Infraction 6s, so I ordered the aluminum center diff case within a couple days of buying the Infraction from my LHS. I think I only ran my Infraction once before changing the center diff case.

 

[Dales396lt4]

I just removed the handbrake all together. At first, I just unplugged it in the receiver box for a while, then when I was sure I did not need it, I removed it.

 

[Jagamov]

Finally got it fully rebuilt last night. USPS was particularly slow with one on my boxes.

200k sure is thick...but I let it sit for awhile and filled it like the instructions show. Did a quick bench test and all seems to work. I wanted to let it sit for a day to let the thread lock cure, so I'll drive it this evening.

Thanks again every one for the tips. Next stop will be to open up the front and rear and check oil levels.