Torque Converter Drain

[Lutzgaterr]

Has anyone ever tried to get all of the ATF out of the TC by the following steps:
1) disconnecting the exit-line from the cooler,
2) have someone start the engine, idle until pump-out 2 or so quarts,
3) kill engine and add new fluid added (same amount-pumped out)
4) start engine and pump-out more
5) repeat until fluid is obviously cleaner or 4 or so quarts have been captured.

Just curious is all.
Hey hey, no flames and thanks in advance .

 

[frickjp]

It holds 9-ish. You can drain out 5-ish with the drain plug. You'll never drain the converter, and running it dry is a bad idea. The cooler comes directly off the pump output, not the converter. ATF is a buck and a half a quart. Drain and fill it every other oil change for a while, and Bob's your uncle.
If you're insistent on getting more out, removing the lower cooler line on the bottom of the trans seems to drain the converter some. After it drains for a day, you may get out another quart or two. Again, bad idea to be messing with 10 year old cooler lines.

 

[sven]

I've done this procedure in my Volvo. I used a clear plastic tube attached to the cooler line, and idled out 1 quart at a time. I ended up using almost a case of ATF. Worked really well!
I've been throwning the idea around with the RRC too. Just never got around to doing it.

 

[curtis]

I would suggest you go to a trans shop and get a trans flush. I did this with Marc Olivares once with a borrowed flushing machine from a Amsoil dealer. You hook one hose up to the cooler input, the other to the cooler output and you can actually watch all of the old fluid going into the machine while the new fluid goes back in. I think you waste about two quarts, but it is the only safe way to do it.

Draining one quart at a time is not a bad idea, but it sure sounds like a hassle.

If you don't have access to a flushing machine, use a shop. Here is what I would do: Go pull your Y-pipe and pull the pan. Put in a new filter and refill the 4 or 5 quarts you can get in. Reinstally pan and Y-pipe and drive straight to trans shop. Have them flush. A flush will run about $75 for non-synthetic or about $125 (I think) for syn. Then you are done. Little to no mess, cheap, and easy.

 

[Lutzgaterr]

Thanks for the feedback to all.

Jeffery,
I have already replaced my cooler lines once they started leaking at around 75K, now at 100K. Running the converter dry, who would agree that this is a good idea anyways and quite possibly I may have an uncle named Bob. I have gotten about 6qrts with an overnight drain, but that is max.

Curtis,
Couple of years ago I stopped by several T-shops and oil-lube shops inquiring about a T-fluid flush. Not a single shop had the right-sized fittings to couple the lines. I was not too interested, else I would have gotten the specs and had a fitting made so they could flush it.

I typically change the fluid at 20K mark and did the filter at the second OCI.
What got me interested in this approach for a complete fluid replacement was my late-night reading about Auto-RX. To use this stuff, they are rather adamant about a complete fluid exchange between cycles, so my old/new mix would not align.

Since she is running fine, I think I will stick to my regular maintenance approach with mixing old/new with 20K OCIs.

 

[marc olivares]

Curtis,
Couple of years ago I stopped by several T-shops and oil-lube shops inquiring about a T-fluid flush. Not a single shop had the right-sized fittings to couple the lines. I was not too interested, else I would have gotten the specs and had a fitting made so they could flush it.
.

i actually had to have lines made up for the ZF transmission (3 different sets for different years)
to be able to use the flush machine on a rover. but Curtis is right, it's the only way to get it all out, w/ out any mess or damage to your pump.

 

[curtis]

Curtis,
Couple of years ago I stopped by several T-shops and oil-lube shops inquiring about a T-fluid flush. Not a single shop had the right-sized fittings to couple the lines.

Thats because IMO most transmission shops are flat-out crooks stealing from low-hanging fruit. In other words they want to service mass-produced makes and do it all in bulk. This still does not mean that you can't find a shop that will do an LR flush. Heck, if you can't find one that will do it just call your LR or BMW dealer and see if they have a machine. If not, ask where they outsource thier work. Buy the advisor or mechanic a six-pack and it will pay for itself many times over