Best way to clean third member

[rosscopeeko]

Hey guys. I bought a used third member for my 97 tacoma 8.4 diff. It shipped in a paint bucket and has a little bit of white paint chips in and around the third member. Overall is doesn't look very clean so i want to clean it before i install it. I did a little reading and it sounds like people use brake cleaner. I want to flush out all the little particles inside. Is there a trick to this without taking stuff apart? I'll most likely fill once it's installed, drive for a few miles, dump and refill. Advice would be appreciated.

[sasaholic]

that shit isnt gunna effect anything. those gears will eat it up in the first 10 feet. wipe out whatever u want and leave it be.

[rosscopeeko]

Yeah i thought the same about the paint, but i'm a little concerned about grit. For instance on some of the ring gear teeth there is the occasional piece of dirt i'm guessing, very small though. I just want it to last so i thought i should clean it out. Also, one of the teeth on the ring gear has a very slight chip on the inside mating surface, about 1/8" x by 3/4" along one of the ring gear teeth. It's only 1/32 deep however. All other teeth look good. Think it will be good for the long haul?

[jski]

Originally Posted by rosscopeeko

Yeah i thought the same about the paint, but i'm a little concerned about grit. For instance on some of the ring gear teeth there is the occasional piece of dirt i'm guessing, very small though. I just want it to last so i thought i should clean it out. Also, one of the teeth on the ring gear has a very slight chip on the inside mating surface, about 1/8" x by 3/4" along one of the ring gear teeth. It's only 1/32 deep however. All other teeth look good. Think it will be good for the long haul?

My engineering background says a chip in a tooth doesn't look good for the long haul... I don't know if others here have actual experience with running on chipped teeth, but in general, once there is a chip in a gear tooth it just gets worse.

A chip starts as a small crack in a tooth. In operation, the gear teeth act as a hydraulic pump and compress the gear oil into the crack. Over time this widens the crack and causes a chip. Once the process starts it just gets worse.

It is possible to reach some sort of equilibrium where the chip is large enough to lower the pressure produced when the teeth mesh to the point where the chip won't grow any larger. This all depends on the geometry of the teeth, strength of the gear material, viscosity of the fluid, RPM, load, etc. This makes it difficult to determine if any given chip will achieve this equilibrium condition.

Now, there is a small glimmer of hope here. The process continues because the gear oil has no place to go but into the chip in the tooth. If the chip extends to the edge of a tooth it gives the oil somewhere to go under pressure. This reduces the pressure produced when the teeth mesh and should prevent the chip from growing.

Your millage will vary, but I would say that any chip on a tooth is only going to get worse.