grease compatibility

[grokcam]

I used traxxas silicone grease inside my gear boxes for the input bevel gear and and the diff. ring gear. I was concerned that it wasn't a heavy enough grease as it seams to spin right of gears. I smeared some of the green hpi heavy diff. grease on the diff. ring gear after wiping as much of the silicone off thru the bottom access hole. Is this a bad idea? I'm concerned with incompatibility between the two types and the hpi stuff seams to spin off just as readily or the silicone still left on the gears didn't allow the hpi stuff to cling to the gears properly. BTW any suggestions for how to clean gears and what solvents or degreasers to use?

[themerc64]

I like to use a more clingy grease on the ring and pinion like automotive white lithium grease. That silicone diff fluid has it's purpose in sealed 1/8 scale buggy/truggy diffs.

[BitHed]

...i use bicycle or automotive de-greasers because they are slightly cheaper and easier to get then an RC dedicated product...Just spray and soak and then wipe clean with an old t-shirt and have a couple of old toothbrushes around for a good thrashing :D

...I know what you mean about compatibility...where possible I try to stay with the same brand in ONE place, or where TWO places will contact each other...I tend to go with TAMIYA brands of grease for lubrication, (whits Ceramic Grease for plastic on plastic and black Molybeden Grease for metal on metal) KYOSHO or MUGEN oils for the diffs, HPI oils for the shocks and different flavours of bearing oils...

...I also use AE Green Slime on my o-rings in my shocks and I have a little container of BadHorsie white silicon grease for when i really want something to slide in / against / on something else...

[grokcam]

Bithead, from the sounds of it you use a solvent-based degreaser in a can? I'm probably just being over-concerned with the effect of harsh solvents on the plastics used for gear boxes, etc. Am I right in assuming no grease is going to stay thick on the gears; they will spin off the excess leaving only a very thin coating on the gears themselves? themerc64, the silicone grease I used came in a tube which I assume is more for applications like the plastic gears in the center gear box rather than the coarse metal gears like the metal input bevels and diff. ring gear.

[themerc64]

grokcam,
I just tore into my diffs today and to my surprise they are sealed on the gear shafts with o-rings. There is no gasket on the diff cup but a little silicone seal would fix that. The stock diff grease looks like bicycle grade lube. I understand your take on silicone based grease being friendly to plastic, but the Armor-All brand spray on protectant has received a very bad rap in the collector car community for being silicone based and has been proven to ruin rubber and plactic instead of preserving it. HPI uses petroleum based greases and they are even more harmful to plastic in my opinion. I like the white lithium grease because it is very neutral and still repels water well. There is another heavy duty synthetic grease I use that can be found at auto parts stores and it is good if you want something really clingy. I also like to use Dawn dish soap, 409, Fantastik, diluted Simple Green, or diluted Greased Lightning ro clean my RC stuff. Dawn being the most mild and Greased Lightning being the most strongest. I find the dish soap cleans up the white grease and silicone shock fluids pretty well.

[grokcam]

themerc64,
I think I might of confused you, I was actually talking about the input bevel gears (to the center drive shafts) and the ring gears outside the diff. cup., not inside the diff. cup assembly itself. I was thinking the silicone grease was too thin to stay on the gears when rotating at speed and would just end up on the gear box walls instead of staying on the gears. But I get the feeling any grease will do this no matter how thick. My thought that silicone grease being more appropriate for plastic gears was based on the assumption thinner grease for finer pitch gears, regardless of gear material, though I have nothing really to substantiate it. I actually used 60K silicone oil inside the front diff. cup and 100K in the rear. I wouldn't worry about the diff cup itself not having a gasket as it seems alot of guys around here use silcone oil without any leakage and I haven't seen anyone commenting on any extra steps for sealing. Thanks for sharing you arsenal of degreasers as I wasn't sure about using soaps/water-based degreasers. Definitely will need a brush with those. I've been resisting temptation to grab the lacquer thinner.:o