Big Rock which diff oil should a use on my Arrma big rock?

[ROCKY OP]

I personally is just a basher, so should i just go with the thickest oil i can find?

 

[dure16]

Stock is 10K. Why do you want to change it?

 

[TimePancake]

10k silicone fluid is stock. No need to have really thick imho 20k should help reduce diffing out. Too thick and it will make the steering feel sluggish

 

[ROCKY OP]

ok thks

 

[Wes13]

10k silicone fluid is stock. No need to have really thick imho 20k should help reduce diffing out. Too thick and it will make the steering feel sluggish

So 20k is better then 10k in big rock?
Use same front & back?

 

[Resu]

I've run once 15k and once 30k but 10k is still the best, so I reverted. Everything thicker will put more stress on other parts.

 

[TimePancake]

So 20k is better then 10k in big rock?
Use same front & back?

I wouldn't say it was better, but I used to find one front wheel would balloon like crazy, which affected the handling. 20k solved that issue, but now has a bit more understeer

 

[Wes13]

I wouldn't say it was better, but I used to find one front wheel would balloon like crazy, which affected the handling. 20k solved that issue, but now has a bit more understeer

Same oil front & back?

 

[GRC]

Thicker diff oil reduces wheel spinout while turning. If you like to spin your car out in turns, you want thinner diff oil. If you spin out too much in turns thicker diff oil will help. Thicker oil in front reduces spinning out going into turns, thicker oil in the rear reduces spin coming out of turns.

I like spinning out my car. When I was driving my Granite with extremely worn out tires, it was obviously spinning out very easily. 20k fluid both front and rear made it much more manageable and quite fun. But now that I've got new tires that don't spin out easily I've gone back to 10k.

 

[TimePancake]

Same oil front & back?

I've got thicker in the front. Helps to pull the front straight out of turns, hence it can be a bit understeer'y.

Thicker in the rear diff promotes oversteer

 

[PatMarcus172]

I have 30k in the front and 10k in the rear on my Big Rock. Not sure I can tell much difference as Ive also changed wheels and shocks.

 

[*420+3RC*]

Hey guys I have a few questions:
1. Just ordered 2 diff from JennysRC. Will they have diff fluid in them?
2. Front diff was locking up. The posts inside(pic attatched) the inset ones are wobbly. Bad?
3. The big gear in there looks like its outer edges were worn. To me. You think?
4. Anything I should do b4 installing the new diffs to prevent quick diff death?

Thank you.
Super newb!

 

[TimePancake]

Can't see the pic you attached. But if you're getting new ones, best check there is enough oil in them, as it can vary from what I've heard. They should be pretty full with the oil of your choice and make sure you grease the outer gears and yolk before fitting back in the car. Lucas red n tacky seems very popular

 

[*420+3RC*]

Hey guys I have a few questions:
1. Just ordered 2 diff from JennysRC. Will they have diff fluid in them?
2. Front diff was locking up. The posts inside(pic attatched) the inset ones are wobbly. Bad?
3. The big gear in there looks like its outer edges were worn. To me. You think?
4. Anything I should do b4 installing the new diffs to prevent quick diff death?

Thank you.
Super newb!

Oops. The 2 that end up being shorter are easily moved. Seems like it would make them bind

Oops. The 2 that end up being shorter are easily moved. Seems like it would make them bind

 

[Puppetman]

I find that 20k in front and back fits my driving style. Everyone is different. Experimentation is part of the fun, I think. My son prefers the stock 10k in front and back on his big rock. His truck has been part of a class we are doing for his homeschool, so we spent a whole week just swapping out diff fluid to test the difference. We only went as high as 30k for the tests, but we sure had fun with it. He loves spinning out and ended up going back to the stock weight.

 

[Atwater]

I just use whatever it available to me lol

 

[razorrc]

4. Anything I should do b4 installing the new diffs to prevent quick diff death?

Yes, loosen your slipper about 1.5 full turns.

 

[*420+3RC*]

Maybe a full turn past that. I had it 11/4 turn from tight.

 

[Ruzty1311]

I use 50kf/30k rear for my Granite and Typhon. If I had a BR I would do the same lol

Those pins are only loose when there is nothing attached to them. Once you add the gears and close up the diff, give it some turns and just make sure there isn't binding. The gears themselves are actually pretty decent and usually don't fail. What WILL fail inside those cups is the plastic seat that the higher pins/gears rest into. Those can crack and you'll know right away that something is wrong because it will be a very audible sound coming from the diff

Hard to tell from the pic but the input gear looks OK? Once you put the diff back together and tighten the yoke down you shouldn't be getting much binding. I have found that there is always a rough spot in one spot when you turn the gears and once you run it the plastic will wear in and that binding usually goes away. If for some reason you install new gearing and tighten down the yoke and you can hardly turn the gears, more than likely your yoke is warped in some say and needs to be replaced. No amount of shimming will help trust me lol

 

[*420+3RC*]

I use 50kf/30k rear for my Granite and Typhon. If I had a BR I would do the same lol

Those pins are only loose when there is nothing attached to them. Once you add the gears and close up the diff, give it some turns and just make sure there isn't binding. The gears themselves are actually pretty decent and usually don't fail. What WILL fail inside those cups is the plastic seat that the higher pins/gears rest into. Those can crack and you'll know right away that something is wrong because it will be a very audible sound coming from the diff

Hard to tell from the pic but the input gear looks OK? Once you put the diff back together and tighten the yoke down you shouldn't be getting much binding. I have found that there is always a rough spot in one spot when you turn the gears and once you run it the plastic will wear in and that binding usually goes away. If for some reason you install new gearing and tighten down the yoke and you can hardly turn the gears, more than likely your yoke is warped in some say and needs to be replaced. No amount of shimming will help trust me lol

Pretty sure I hit the nail that time. After putting it on a easy spin pin. Homemade contraption. With light behind it. B4 and After I sanded all way around it looked warped. Gonna put a thread out tonight after work. I believe it may have got a little too hot in my car or work van. And warped diff things. I just don't know what all it could be. And. Need a fresh thread so I can keep up with everyones thoughts. Thanks man