HELP!!! Diff grease or oil ?

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Jason808

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Please help, I recently installed Hot Racing diff cases front and back and I used 30k diff grease. Now the truck sounds like it’s slipping and I lost all power. The truck still runs but just sounds weird and lost power. Everything is tight , could it be the grease? Not sure if I should be using oil or grease? Should I check the gear mesh?
Thanks
 
Did you use this diff fluid

91E5F849-234B-4C51-93EB-9732696FB898.png
 
Please help, I recently installed Hot Racing diff cases front and back and I used 30k diff grease. Now the truck sounds like it’s slipping and I lost all power. The truck still runs but just sounds weird and lost power. Everything is tight , could it be the grease? Not sure if I should be using oil or grease? Should I check the gear mesh?
Thanks
You use grease on the ring gear. If it's slipping, check the gear mesh between the ring gear and pinion. You may have to shim the diff between the diff and the diff case on the ring gear side to tighten up the gear mesh, or you may have to shim the pinion gear shaft to get the pinion closer to the ring gear.
 
@Jason808 No such thing as 30k GREASE!!!!. You screwed up if you used grease inside the diff cup. Sil. OIL only. Not sure what you did there. It is unclear.
But Grease is only used at the Main and Input gears.
And any grease is considered and equivalent to only 1k CST Oil!
Much too thin for the diff cup's Satellite and Sun gears.
Big Mistake if you used grease inside the diff cup.
Buy and use 30k cst silicone oil inside the diffs. Then only grease on the outer gears. Do it the correct way.
You may have just assembled the diffs wrong. Needing shims. I don't know what you did there. :whistle:

Please give more correct accurate info so we can help better.:cool:
 
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Did you use this diff fluid

View attachment 195732
No, it was a grease made by kyosho.
@Jason808 No such thing as 30k GREASE!!!!. You screwed up if you used grease inside the diff cup. Sil. OIL only. Not sure what you did there. It is unclear.
But Grease is only used at the Main and Input gears.
And any grease is considered and equivalent to only 1k CST Oil!
Much too thin for the diff cup's Satellite and Sun gears.
Big Mistake if you used grease inside the diff cup.
Buy and use 30k cst silicone oil inside the diffs. Then only grease on the outer gears. Do it the correct way.
You may have just assembled the diffs wrong. Needing shims. I don't know what you did there. :whistle:

Please give more correct accurate info so we can help better.:cool:
Hey thanks for the response. So when I replaced the front and back diff covers, there was grease inside on the gears so I assumed that’s what I needed. Not sure by what you mean by the outer gears. However I did add a shim to the back to tighten up the mesh.
 
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No, it was a grease made by kyosho.

Hey thanks for the response. So when I replaced the front and back diff covers, there was grease inside on the gears so I assumed that’s what I needed. Not sure by what you mean by the outer gears. However I did add a shim to the back to tighten up the mesh.
image.jpg

This was the part I replaced with a hot racing one, front and back, everything else is stock. This is for a Notorious V5. And yes, it’s a whining sound and no clicking but exactly how you described it is what it’s doing.

image.jpg

image.jpg

This was the part I replaced with a hot racing one, front and back, everything else is stock. This is for a Notorious V5. And yes, it’s a whining sound and no clicking but exactly how you described it is what it’s doing.

image.jpg
To clear some things up, I never added grease to the diff cups just the outside gears and I never touched the center diff since I owned this truck. I doubled checked front and back diffs and everything is tight and seems correct. Maybe the slipper needs maint, not sure. Sorry I hope this helps and thank you for all your guys feedback.
 
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Ah, so it must be the mesh for one or more of the diffs you added grease to. You've probably shimmed the diff ring gear(s) too tight against the diff input gear(s). To find out easily:

Remove the centre diff and both centre driveshafts, then roll the truck's wheels on the floor. You'll be able feel whichever diff has resistance. Both the front wheels and the rear wheels should roll freely without any binding feeling whatsoever

Also - the grease you used is probably for diff internals gears if it specified it was 30k cSt (for internal diffs that aren't sealed with a gasket). What you should use instead is a synthetic lithium based grease. 30k cSt grease used inside the bulkhead for the ring/input gear will likely cause a lot of unnecessary resistance and heat for the gears and electronics. If it's really thick and gloopy - I would take it out ASAP
 
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Ah, so it must be the mesh for one or more of the diffs you added grease to. You've probably shimmed the diff ring gear(s) too tight against the diff input gear(s). To find out easily:

Remove the centre diff and both centre driveshafts, then roll the truck's wheels on the floor. You'll be able feel whichever diff has resistance. Both the front wheels and the rear wheels should roll freely without any binding feeling whatsoever

Also - the grease you used is probably for diff internals gears if it specified it was 30k cSt (for internal diffs that aren't sealed with a gasket). What you should use instead is a synthetic lithium based grease. 30k cSt grease used inside the bulkhead for the ring/input gear will likely cause a lot of unnecessary resistance and heat for the gears and electronics. If it's really thick and gloopy - I would take it out A

Thanks for the info , I’ll try removing the one extra shim and see what happens. This was the grease I used, found it on Amazon and it said diff grease so I assumed that was it. Gonna pickup some lithium grease and give it a shot. Thanks for the help.

215F1BDD-B2AF-4674-B8C8-43DCA5BF8360.png
 
Ignore the advice I gave earlier. I thought you were talking about a 3s Arrma. It did not apply to a 6s rig. 6s Arrma's don't have a slipper.
Good to know, so just gears and pinions in the 6S rigs correct? So long as everything is snug and greased in the diffs, should be ok? Thanks
 
There is a lot we don't know about our diff and shock oils/greases. The single data point in cSt can be taken several ways. Ultimately, we decide using our eyes and controls that an oil is right or wrong, but one size may not fit all...

Chevron tech bulletin - viscosity (.pdf)
 
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