Diffs Getting Hot

[Spive]

Hi everyone,
I am running an mt410 with gamechanger chassis. Castle mmx8s esc, 1520/1650kv motor, 22t pinion, 4s batteries. On my first run I had 100k fluid in the center diff. I checked it after 15min and the center diff was 190 degrees. So I upped all the diffs to 100k rear 500k center 200k front. The center is still hitting about 160 degrees and the out drives on the rear diff are at about 140 so I’m sure the internals are even hotter. The front is fine. It’s a brand new build so I’m pretty sure the bearings are ok and the spur seems to turn freely when I turn it manually. Has anyone else running this setup experienced this? Is it too much torque for the diffs? Do I need to go with a smaller pinion or just heavier diff oil? Or could it be something else.

Thanks

 

[Spive]

I forgot the tires. I’m running arma backflip 4s.

 

[nitro]

22t pinion is ginormous for a Tekno. 18t is big. Not sure if that's the only problem though.
They have high volume metal diff cases for doing crazy stuff

 

[Nicochau]

When you get close to 180F on a diff or a motor, you need to change the bearings. Reason is the grease will break at this point and seperate into oil and the thickening agent. The oil will be eliminate fast and only the thickening agent (soap like) will remain… you may not notice it at low speed, but the bearings are shot and will overheat from there…

With the the type of power you’re running, upping significantly your diff fluids should be sufficient. As an example, the new Traxxas Sledge has 20 mil in the center diff!

 

[RC_User]

for what you're running i'm not surprised they're getting so hot, this is why they make the alloy diff cases, i'd invest in a set.

 

[Spive]

for what you're running i'm not surprised they're getting so hot, this is why they make the alloy diff cases, i'd invest in a set.

Yep I ordered some.

 

[Spive]

22t pinion is ginormous for a Tekno. 18t is big. Not sure if that's the only problem though.
They have high volume metal diff cases for doing crazy stuff

Well I’m running a 1650kv motor on 4s batteries so I think I need the bigger pinion. The car does about 50mph like this. My understanding is a 2200kv motor with a17t pinion would do about the same. Is that not right?

 

[nitro]

Well I’m running a 1650kv motor on 4s batteries so I think I need the bigger pinion. The car does about 50mph like this. My understanding is a 2200kv motor with a17t pinion would do about the same. Is that not right?

yeah sorry missed the 4s part.

 

[Nicochau]

Well I’m running a 1650kv motor on 4s batteries so I think I need the bigger pinion. The car does about 50mph like this. My understanding is a 2200kv motor with a17t pinion would do about the same. Is that not right?

That is correct, but with a lot less torque.