so im putting silicon diff fluid in my car, what are all theese fluid weights? 50k, 5000cst, 50weight? Im sure they are just diferent units of viscosity measurement right? And whats the best way to clean out this silicon fluid? Also do i just fill the case all the way up or what?

yeah they are just different viscosity ratings. i have found the best way to clean the diff is to use degreaser (the one that doesnt leave any residue behind), spray the gears and just basically clean the whole diff up with it and then put your gears back in and fill the diff upto the top of the satellite gear (about 80% full) and put it all back together.

you should also change your o-rings in side the diffs and maybe your bearings if they are bad.
hope this helps.

I don't really know how the weighing works. I just changed my diff oil in my buggy to 5k, 7k, 3k. 5 in the front, 7 center, and 3 rear. The weights are just different viscosity ratings. So just take out your diffs and clean them out. Don't fill your diffs all the way up. Fill it up to the top pin. You will know what I mean when you take it apart and see the two pins that hold all the gears on.

Go to the hardware store and buy yourself a can of Naptha. (usually in the paint isle)

Use it with caution, as it is very flammable.

It will remove ALL grease and silicone oil from the diff parts with little to no effort and a little goes a long way.

Put some in a disposable container of some sort and then dump in your diff parts.
Swirl it around every few minutes and in about 5 minutes or less the parts are clean.
Put them on a towel to dry, (dries up quick), replace your seals, re-assemble, pour in new oil and go.

As stated above, you don't want to overfill the diff with oil, or it WILL leak when it heats up.
Fill to just above the pins.

You didn't say what vehicle this is going in, but a good rule of thumb is buggy 5K front, 7K center, 3K rear oil and truggy 7K front, 10K center, 3K rear.

This will get you going in the right direction for 90% of the cars/trucks on the market.
Lighter oils make it easier to drive, TO A POINT.
Too light and it will diff out and become a bear to drive.


BTW, if the store doesn't have Naptha, you can substitute Ronsonol lighter fluid(like what you would put in a Zippo lighter).
Same stuff.

Whatever you do, NEVER use carb cleaner on any plastic parts.

Don't ask me how I know this.........


Scott