Warming the Transfer Case (for fluid change)

[97XJ2]

I read somewhere (on here) about warming up the transfer case to make changing the fluid easier. I have the 242, so could i just drive around in 4fulltime for ten minutes?

 

[the_weirdo]

That should work fine.

 

[scorpio_vette]

you can drive it in 2wd for 10 minutes or in 2wd for 10hours. or in 4wd. whatever you want. either way, your transfercase is going to be spinning and pumping regardless because it's driving the rear axle. so therefore it'll be good and warm either way.


oh and one more thing........you are overthinking the situation a little.. drain it warm, drain it cold. either way.......just do it.

 

[600dollarxj]

I dont think you really need to warm it up. ATF is pretty thin

 

[Blaine B.]

Well, it's not necessarily about the viscosity. Particles will be stirred up and not sitting at the bottom of the tcase when it is drained. You'd rather have those particles mixed up with the fluid when draining, rather than bunched up in a corner and not flowing out.

 

[scorpio_vette]

technically speaking, there shouldn't be any particles floating around. that's what the magnet in the bottom of the t-case is for. and as long as the particles are stuck to the magnet, it doesn't matter if you drive it for 100hours straight and then drain it, the result is going to be the same. fluid comes out and particles are stuck on magnet.

 

[TiRod]

Some particles bond up in a corner of the case despite the extreme detergent additives of ATF. They just don't come out. And friction lining, aluminum specks, and other nonmagnetic materials just don't stick to the magnet.

Putting in fresh fluid renews the additive package and increases the lubricating ability - especially on old, overheated fluid. It will certainly extend the life of the tranny compared to the average drive it and forget it approach.

 

[Blaine B.]

A magnet can only hold so many particles though. Plus I'm sure there are non metal particles as well, like dirt and crap that can be stirred up and not settled.

 

[scorpio_vette]

"generally" speaking, there shouldn't/won't be any decent particles in there that will get flushed out. plus the drain plug isn't exactly under the t-case. so the particles would have to flow slightly up to get out of the plug. plus the time between you parking it, jacking it up and draining it will be enough for any particles to settle.

and if you have "dirt and crap" in your t-case, then it would be time to start replacing seals.

 

[97XJ2]

thanks for the input, i actually hadnt checked in on this thread since the first reply. For what its worth i put it in full time and got it up to temp, drained and refilled. Though now i want to rebuild the case, i found a little chunk of rubber inside the drainhole (When I had it checked out before I bought the Jeep the mechanic said there was a little rubber plug on top of the case that was missing, he replaced it. I guess i found it) But i think I'm leaking a little from the seam somewhere, I'm gonna keep an eye on it.