Big Rock Arrma big rock rear diff
- Thread starter Bigrayzrc
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get a stock one from a kit breaker like jennys on the cheap
parcou
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Sorry to hear that.... Jenny's is the cheapest way to go.
How do you have that setup...? Belted tires, heavy diff fluid...also check the diff shim you need a shim on the crown gear side...could need two but check the mesh between the input and the crown.
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Yea I probly do need to put some shims in it. What size should I get?
Sorry to hear that.... Jenny's is the cheapest way to go.
How do you have that setup...? Belted tires, heavy diff fluid...also check the diff shim you need a shim on the crown gear side...could need two but check the mesh between the input and the crown.
Hector_Fisher
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If you don't want to spend money on an upgrade, then your only real option is replacement. There aren't any "cheap" upgrade options here, unfortunately.
Personally i've had good experience doing a proper rebuild of the rear diff (always replace those gears in a set) and it's lasted quite a while and a good amount of hard bashing. Cleaning the housing, new bearings, don't over-tighten the yoke, shim the diff, checked for free spinning, and then grease. Should last quite a while unless your abusing your drivetrain (landing on power, lots of shock loading, running 4s, heavy tires, etc). In which case, you'll probably want to spend the extra money and just get the steel gears from HR or Arrma.
Personally i've had good experience doing a proper rebuild of the rear diff (always replace those gears in a set) and it's lasted quite a while and a good amount of hard bashing. Cleaning the housing, new bearings, don't over-tighten the yoke, shim the diff, checked for free spinning, and then grease. Should last quite a while unless your abusing your drivetrain (landing on power, lots of shock loading, running 4s, heavy tires, etc). In which case, you'll probably want to spend the extra money and just get the steel gears from HR or Arrma.
parcou
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There should be one on there now. It would be the same size and part number.
When checking the shim on the 3S diff needs to assemble it while in hand check the mesh. You cannot visually see it all that well so I go by sound and feel.
Puddlejumpernva
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I have burned through several of these diffs.. Arrma really should not be charging as much as they do for the metal upgrade. Very frustrating...
Setup is important but plastic is plastic. My next one will have a metal yoke, hoping that will reduce the flex and make it last longer. Oddly enough one of our 3s rigs is on the original diffs and it gets abused pretty hard... Maybe since it never lands on the tires it's OK
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Once you get the slipper and diffs dialed in and seal the power module these rigs are Tough! They take hits that would bend any of the other lines for sure.
I just wish the 4s metal diffs came stock. If Redcat can include metal diffs on the Volcano so can Arrma, no excuse. (My redcat has never even had the diffs apart after 15 packs or so).
Setup is important but plastic is plastic. My next one will have a metal yoke, hoping that will reduce the flex and make it last longer. Oddly enough one of our 3s rigs is on the original diffs and it gets abused pretty hard... Maybe since it never lands on the tires it's OK
. Once you get the slipper and diffs dialed in and seal the power module these rigs are Tough! They take hits that would bend any of the other lines for sure.
I just wish the 4s metal diffs came stock. If Redcat can include metal diffs on the Volcano so can Arrma, no excuse. (My redcat has never even had the diffs apart after 15 packs or so).
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