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Torque converter plug

I have a 2000 Mercury Grand Marquis LS and I want to change the transmission fluid. The manual says to drain the torque converter and to do this you must remove the plug on the converter ( ok so far). It then states that you MUST use a new plug after the converter has been drained before refilling the transmission. I called my local Mercury dealer to purchase a new plug and they told me that the plugs are no longer available. Thus my question—do I really need a new plug (aren’t they basically just an oil pan type plug) and/or if I do need one, where do I find it whereas my local parts stores tell me that it is a dealer item?

Have you tried another dealer or online? Maybe your dealer can’t get one but someone probably has some sitting on the shelf. Remember, you should try Ford dealers also, not just Merc dealers.

Failing that, unless the fluid is burnt or otherwise contaminated, you should be fine just dropping the pan and replacing the filter and the partial amount of luid that comes ou. Repeat 25K miles from now.

Most people don’t replace the plug. I think it is just tapered pipe thread of some type so I don’t understand why you would have to replace it. Ford decontented the plugs on the 4R70W ca. 2002, IIRC. I could be wrong. Are you sure you have one? Just because there is a plastic/rubber plug in the housing inspection hole does not mean the TC has a drain plug. If you can not find out for sure, you have to turn the TC over and check the inspection hole to look for it.

If you do want to replace the plug there are some solutions. First, try another Ford, Lincoln or Merc dealer. Some of those parts counter people are idiots. Ford may had stopped selling them, however, because their prescribed procedure now is to flush them through the trans cooler lines. You could try a transmission repair shop.

You need about 15 quarts to service the trans. at least every 30K. If you only drop the trans pan, you will get less than half the fluid out and have to replace the fluid very frequently because it is an inefficient way to do it. You NEED Mercon V fluid. Accept no other fluid.

Ask at if you have one. There is also a good tech section that includes procedures for transmission service. There is lots of other information for you that will help you keep that ol Panther going.

Shoot, Ford/Lincoln/Mercury dealers had computerized access to each other’s parts inventory over 30 years ago when I worked for one. I found a dealer in another state who still showed several New Old Stock Model “A” head gaskets. I requested one. He was required by his franchise agreement to send it back to the depot which forwarded it to us. Ford probably hadn’t made those gaskets in 25 or 30 years.

OTOH, reusing the plug, if your model even has one, isn’t going to hurt anything. I’ve done it that way many times.

Check the dipstick for the proper fliud type, and the manual for the correct quantity.