Big Rock Arrma nero big rock tear down and complete rebuild

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So i somehow ended up buying a Nero Big rock in a okay condition. Im the third owner of this truck according to the seller. It popped up on marketplace for a price of 325$US aproximatively with some spare parts.

The diff brain works and all the drivetrain seems to be in a working order, body shell itself is in good contition with only one crack at the rear. It was extremly dusty. This is how it looks like after a vaccum clean and a leaf blower
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Now for the bad. A lot of rock damage in the rear arms and aluminum slicers. He told me he drove it mostly on gravel. He didnt have mud guards on so the whole rear suspension got hammered with pebbles. Other than that the other big issue i see is that the body stickers decided that they didnt want to live anymore. I need to find a way of fixing that if anyone has any tips on how to do it pls let me know. Another issue the deive pins. He had a ton of them as spacers and i noticed those pins are mostly junk because they are undersized and has ton of play of course they going to snap. If again someone has a libk for better pins who are bigger let me know.
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Now the teardown process begins. Idk where to start. This might be a long learning curve on how everything goes togueter.
I also got 4 3s hrb 6000mah lipos but they are ruined. They were fully charged for too long or its because of how they were connected to the truck. The esc has traxxas connectors on with xt60 adapters . The IR seems okay but they puffy. And i have to storage them asap
 

Tex Koder

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Traxxas makes a drive pin (for their e-revo) that fits these cars well. I don't remember the PN# though.

Or make your own by cutting some out of drill bits of the same diameter..


*************

Now for the bad. A lot of rock damage in the rear arms and aluminum slicers. He told me he drove it mostly on gravel. He didnt have mud guards on so the whole rear suspension got hammered with pebbles. Other than that the other big issue i see is that the body stickers decided that they didnt want to live anymore. I need to find a way of fixing that if anyone has any tips on how to do it pls let me know. Another issue the deive pins. He had a ton of them as spacers and i noticed those pins are mostly junk because they are undersized and has ton of play of course they going to snap. If again someone has a libk for better pins who are bigger let me know. View attachment 270373 View attachment 270374 View attachment 270375 View attachment 270376
Now the teardown process begins. Idk where to start. This might be a long learning curve on how everything goes togueter.
I also got 4 3s hrb 6000mah lipos but they are ruined. They were fully charged for too long or its because of how they were connected to the truck. The esc has traxxas connectors on with xt60 adapters . The IR seems okay but they puffy. And i have to storage them asap

Are there mounting holes in the rear suspension arms -to allow for mudguards installation?

Let me know ,perhaps I can 3D design something for it..
Just need some measurements.
 
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Or make your own by cutting some out of drill bits of the same diameter..


*************



Are there mounting holes in the rear suspension arms -to allow for mudguards installation?

Let me know ,perhaps I can 3D design something for it..
Just need some measurements.
They have to be threaded
Or make your own by cutting some out of drill bits of the same diameter..


*************



Are there mounting holes in the rear suspension arms -to allow for mudguards installation?

Let me know ,perhaps I can 3D design something for it..
Just need some measurements.
Yes they do. I have a 3d printer and im going to build something for it. Theres also mud guards available from arrma for it. But i prefer to make my own. Makes me be more used to designing in CAD and costs pennies to make
Been thinking making tpu mirrors for my corvette c8. And headlights and tailights for leds but im not yet to that level. And me living in canada going to cost me an arm
 

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The rear diff had ton of in and out play. Took it out. The bulkhead was packed with sand and dirt took a lot of playing to take it out but the inside of the gearbox itself had nothing. I think its the first time this car gets any form of diff maintenance. The crown gear looks like new same for the sun gear. Opened the diff up and i didnt see anything wrong sk im kinda puzzled. The front has also play but a lot less.
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The sun gears are 2 different sizes im wondering if it can even take silicone oil. The manual says to use grease
Its so dirry man you can believe
 

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God it cannot take oil or its going to leak... well poop
Might completely rmove the diff brain for the fron and center buy a nee cup for the center and seal it up with the screws method. I don't need a diff lock in the front in the rear i can see the apeal and the center well i feel like its going to terrible power bleed to the front tires. Its something that caught me like that that the diffs are not fully sealed. It has an oring behind outside the diff lock holes but is it enough to seal it??
 
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God it cannot take oil or its going to leak... well poop
Might completely rmove the diff brain for the fron and center buy a nee cup for the center and seal it up with the screws method. I don't need a diff lock in the front in the rear i can see the apeal and the center well i feel like its going to terrible power bleed to the front tires. Its something that caught me like that that the diffs are not fully sealed. It has an oring behind outside the diff lock holes but is it enough to seal it??
If you remove the front and rear diff locks, you should leave the center functioning. When locked, it'll keep the power from bleeding to the front, and the truck drives much better this way, imo. The slipper will protect the drivetrain, as long as it's not fully tightened. I believe the reason for the diffs being filled with grease instead of silicone oil is due to the diff lock pin holes. The Nero platform all used the same diff cups with or without the diff-brain. Hope you have fun with this rig.
 

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If you remove the front and rear diff locks, you should leave the center functioning. When locked, it'll keep the power from bleeding to the front, and the truck drives much better this way, imo. The slipper will protect the drivetrain, as long as it's not fully tightened. I believe the reason for the diffs being filled with grease instead of silicone oil is due to the diff lock pin holes. The Nero platform all used the same diff cups with or without the diff-brain. Hope you have fun with this rig.
If you remove the front and rear diff locks, you should leave the center functioning. When locked, it'll keep the power from bleeding to the front, and the truck drives much better this way, imo. The slipper will protect the drivetrain, as long as it's not fully tightened. I believe the reason for the diffs being filled with grease instead of silicone oil is due to the diff lock pin holes. The Nero platform all used the same diff cups with or without the diff-brain. Hope you have fun with this rig.
Idk of it can hold oil from what i read it doesn't but it has an oring around the holes but the diff moves in and out a bit so i doubt
 

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I love the hard springs. You might think they are too much, but they really aren't. I wouldn't recommend a spring softer than 15lbs.
Just noticed arrma makes longer apeinga for the big rock 75mm from 420gf to 317gf who is 17lb inch.
 

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All the parts have been cleaned the best i could with elbow grease. Now the electronics to clean up and 2 more diffs. That is the thing i hate the most. Cleaming freaking diffs pain. I might buy the red body shocks and center chassis. The nero platf9rk was really a show piece and im going to shelf queen it when not in use and dull brown aint really doing it. But those chassis plates are freaking expensive 50$ a pop.
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The car came with hot racing 5mm+ width thingies. Look kinda nice but i don't like how the hexes are keyed. Made some little buldges on the wheel hexes and i don't wabt that to happen on my other tires. Might just go back to stock. Waiting for the bearings to come in also from jimbearings.
Stickers also ordered.



The two diffs i took apart and the cebtwe transmission has 0 wear. No shark fins anywhere not even on the spur gear or clutch gear. Cant say the same about my 6s exb spur gears and soon my felony c8 pinion going to lose its teeths. Its the clutch doing saving the nero from wear or the quality of the metal they now use is no way near as good as before
 
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