Granite When should I inspect my diffs?

[TCRC granite]

Hi, I've owned a granite blx 3s for over a year now, amd i run it very light almost every day. Just wondering if i need to inspect or relubricate the diffs? Thank you!

 

[rceverywhere]

I'm pretty sure the book usually says every ten packs, but you can wait till something starts to make noise, then open it up and make a list of the parts you need. I usually do the latter also. Lol

 

[Senton_Prime]

Before you even pull it out of the box..

 

[TCRC granite]

Well, it runs great. I just go through suspension arms like crazy!

 

[Robbbbbb66]

Before you even pull it out of the box..

View attachment 317871

How do you take the diffs out when the box is sealed???

 

[TCRC granite]

Box? When i take off the front/ rear skid plate some oil comes out, is that normal?

 

[rceverywhere]

Oil not normal, but there is grease on the ring and pinion gears that gets flung off during use. That would most likely be what your seeing one the skid plate. It would be the skid plate that acts as the sealing of those gears to protect them from dirt and stuff from going in. Also with the skid plate off it gives you a chance to inspect the gears for missing teeth, backlash to loose and to add some heavy grease to them easily. If it's oil, it could be leaking out of the inner differential gears, usually it stays in but sometimes a silicon diff locking oil gets put in then comes out

 

[MrTitanium]

First things first. I take apart my diffs as soon as I take the RC out of the box. Be it an Arrma or other company, I have very little faith in people’s work ethics. Inspect and shim as needed.

After initial inspection, I inspect diffs every 25 to 30 runs. Might seem excessive to some, but I know firsthand what a bad $5 bearing can do to a set of gears (I think most of the fellas here know).

 

[TCRC granite]

I see what your saying. What kind of grease do you use? The screw holding the skid plate on goes all the way through the diff casing. It was nearly brand new at the time, so I'm not worried about it. I haven't had diff trouble though, they seem pretty good. What about the center diff on fireteam? It seems EXTREMELY tight for some reason. It is actually somewhat hard to turn when it is off of the truck.it's like a $60 part, so i don't want to go fittling with it if it's fine. Thanks for the input!!

 

[hobo]

I service my diffs maybe every 30 to 40 packs ish thats on the 6s cars though

 

[rceverywhere]

I see what your saying. What kind of grease do you use? The screw holding the skid plate on goes all the way through the diff casing. It was nearly brand new at the time, so I'm not worried about it. I haven't had diff trouble though, they seem pretty good. What about the center diff on fireteam? It seems EXTREMELY tight for some reason. It is actually somewhat hard to turn when it is off of the truck.it's like a $60 part, so i don't want to go fittling with it if it's fine. Thanks for the input!!

Any heavy grease is good, something that will hold on under the stress. Personally I've always used flex shaft grease for rc boats. Has anti fling tech and water resistant, plus you can get it with a little thumb pump and just change the tube after, it takes a long time to empty a tube, had it allready anyways, you can used normal automotive wheel bearing grease or just about any grease the thicker the better you just want it to stay on the gears as just running them the grease want to fly off.
The center diff will have thick silicone oil in it and normal to be hard to turn, the oil viscosity can be changed to achieve a more or less lock effect to the spider and axle gears

 

[SrC]

I service my diffs maybe every 30 to 40 packs ish thats on the 6s cars though

Same here. I can get that much run time out of mine, depending the 6s rig it is. However Right out the box you MUST open them up, top off the fluids or choose your own CST oil then shim the diffs properly. You will get much life out of the 6s diffs this way. Your mileage will vary of course.
Even with the 4x4 diffs, you really need to check them right out the box first. Oil usually being low. Common.
If you do this, you will break way less parts during the long haul, while just needing to refresh the oil and keep rolling.

 

[TCRC granite]

Ok, thanks. I haven't had any trouble with them so far. What about the center diff on fireteam? Is it supposed to be nearly to tight to turn? It turns smooth, just with a lot of pressure!

 

[King blitz]

How do you take the diffs out when the box is sealed???

Very carefully

 

[TCRC granite]

What grease should i use?

 

[rceverywhere]

Ok, thanks. I haven't had any trouble with them so far. What about the center diff on fireteam? Is it supposed to be nearly to tight to turn? It turns smooth, just with a lot of pressure!

What grease should i use?

Any heavy grease is good, something that will hold on under the stress. Personally I've always used flex shaft grease for rc boats. Has anti fling tech and water resistant, plus you can get it with a little thumb pump and just change the tube after, it takes a long time to empty a tube, had it allready anyways, you can used normal automotive wheel bearing grease or just about any grease the thicker the better you just want it to stay on the gears as just running them the grease want to fly off.
The center diff will have thick silicone oil in it and normal to be hard to turn, the oil viscosity can be changed to achieve a more or less lock effect to the spider and axle gears

Maybe I over complicated the explanation, it's all there but I added more than you asked

 

[TCRC granite]

I'm Sorry, i didn't even see that reply! Thank you very much you all are very helpful. This forum is great!

 

[SrC]

Ok, thanks. I haven't had any trouble with them so far. What about the center diff on fireteam? Is it supposed to be nearly to tight to turn? It turns smooth, just with a lot of pressure!

Yeah the FT actually comes with 200K Cst at the center stock from the factory. Thicker/tighter to rotate by hand. Normal. Most others come with only 100k. I actually upped my FT to 700 k at the center. Best for me. I found 500k was even too thin. My FT center diff gets super hot with thinner oil, IMHO. My temp gun shows the diff at over 200F sometimes. I was even considering 1mil. I have on hand.
FT is rather Heavy and Long and really taxes the center diff.
Probably why the FT is the only 6s Arrma to come with the Upgrade metal Option diff out the box.

 

[hobo]

Yeah the FT actually comes with 200K Cst at the center stock from the factory. Thicker/tighter to rotate by hand. Normal. Most others come with only 100k. I actually upped my FT to 700 k at the center. Best for me. I found 500k was even too thin. My FT center diff gets super hot with thinner oil, IMHO. My temp gun shows the diff at over 200F sometimes. I was even considering 1mil. I have on hand.
FT is rather Heavy and Long and really taxes the center diff.
Probably why the FT is the only 6s Arrma to come with the Upgrade metal Option diff out the box.

where did you get the 700k from did you do some mixing

 

[SrC]

^^^ I mixed 500k with 1 mil.
Yeah, I never seen 700k myself.
Mixing is ok.
But it is a rough approximation, that can work.
I could have went straight from 500k to 1 Mil. A big jump ...
But I don't like to overshoot diff Oil cst.
I work my way up a little at a time., evaluate from there.