Differential Silicone Fluid - grey?

[cbreaker]

Hey guys,

I think this is normal from what I've been able to peice together from here and there, but I thought I might ask anyways.

I took apart my center diff today and found that the 7000wt fluid I put in there about two months ago has turned a rather dark shade of grey. It was perfectly clear when I put it in.

What is the deal with this? Does it change color when it gets used/hot? Is this normal, and am I okay?

Thanks in advance.

[FlyinRazorback]

Yes, this is normal. Not exactly sure where it comes from or what causes it, but it happens with all diffs, even after a few runs when new. Just clean the old stuff out real good and put some fresh fluid in. I usually clean mine every 1-2 weeks.

[cbreaker]

I'll definately change out the fluids more often once I get to be able to use it more often. As it stands right now it still gets dark and cold at 5:30pm and I get home from work at 5:50pm. So that means only being able to use the buggy on the weekend, and that's if it's not 30 degrees outside and/or raining or snowing.

I've probably used my buggy 1/4 the amount in two months that you've used in a single week =)

I think I'm going to get the dynamite center diff mount kit. I like the idea of being able to pull out the diff a bit easier. The front and rear are already pretty easy on the storm; like 6 screws each side.

[wannarunem]

hey cb..ive got that dynamite center diff mount.....it rocks, sure saves some time

[El Pirata]

The grey substance that used to be clear is aftually the same substance with tiny metal shavings coming from your gears meshing. It is completely normal unless you find really large shavings in there.

[FlyinRazorback]

Originally posted by cbreaker
I've probably used my buggy 1/4 the amount in two months that you've used in a single week =)

Monday through Friday my buggy sits on the desk. I only run it on raceday. After one or two races, it gets new oils in the diffs and shocks.

[GilBeQuick]

Woah man, that's pretty hardcore. Is that normal for people who race to change fluids THAT often??

[HP Invent]

Originally posted by El Pirata
The grey substance that used to be clear is aftually the same substance with tiny metal shavings coming from your gears meshing. It is completely normal unless you find really large shavings in there.

It happens to all cars ( offroad and onroad ) that run oil diffs.

[cbreaker]

Apparently this happens not only in R/C vehicles, but 1:1 vehicles too.

Your transmission fluid in your car starts out a clear red color. After awhile it becomes opaque from the metal dust from the gears wearing out.

Apparently, you're not supposed to do a full transmission fluid change on your car past 100k miles. You do a partial fluid change. The gears have worn enough that the metal dust in the fluid actually helps thicken the fluid and offset the fact that the gears have more play. If you change out the fluid completely, the gear teeth end up whacking each other pretty hard and you'll be lucky if you get another 5k miles out of it.

Getting to know how these things work has really taught me a lot about other things too!