A few years ago, I purchased a transmission out of a wrecked 4Runner. I bought it, anticipating needing it as my original was nearing 300,000 miles. Well, as 4Runners tend to do, mine lasted much longer than I expected, I am now nearing 435,000! So, it sat in my garage for a couple of years. Anyway, it looks like it may be time to finally install this thing, as my original doesn't seem to want to kick down anymore, and I am getting some weird vibrations (maybe unrelated).

So, my question... How should I prep the "new" transmission after it has been sitting fo so long? It has a few quarts of fluid in the pan and the converter is full as well (converter is sitting flat, I figured that it should probably be stored with fluid in it).
I am thinking that I will start by dropping the pan and cleaning the filter. Once I get it installed, would I just drain and fill the fluid as I normally would (I usually do the "drain a few quarts/ add a few, repeatedly until it is nice and red" method). Is there anything else that I should do before or during the install!

I've seen lots of threads on installing transmissions, but couldn't really find one that talks about how to deal with one that has sat for so long.

Anyway, thanks for reading. And please share any advice you may have!

Sitting in a garage? Can't really imagine what might happen to it unless water was already in it. I'd be more concerned about the condition of the clutch plates but it is sealed pretty good.

First thing I'd do though is check for critters who found a home in it or chewed on the wiring.

whats the cost to get it rebuilt? Seems like a lot of effort to pull it out and put it back in without knowing the condition.

I do know the condition, aside from sitting for a while. It was purchased from someone that I know, his truck was well maintained.

Seems like it should be fine, drain the fluid and go from there. Don't over think it.

Have you tried adjusting the kick down cable on your current transmission?

You shouldn't have to do anything to it but install it. You can drop the pan and replace the filter (don't clean the filter, it's nearly impossible to clean the entire screen area).

Once you get it installed, I would do a full fluid exchange (pump a quart out, fill a quart about 13 times).

I would just look it over real good and make sure the wiring isn't compromised and there aren't any cracks/leaks.

I would replace the pump seal and the filter, install the transmission, fill it, unhook one of the cooler tubes, put a hose on it emptying into a bucket and start the engine. As the fluid pumps out of the disconnected cooler tube keep adding fluid through the dipstick tube until you have run 8 or 10 quarts through it. Reconnect the cooler line and fill the transmission to the proper level with the proper fluid.

I would think seals seals seals on a sitting trans.

It may even need replacing. That said at his mileage F it and replace the whole thing. That isn't a fun job.

Not yet, but that is on my to do list. Hopefully its that simple.

That is how I have usually done it in the past. Makes it a pretty easy job... Unless you pull the wrong line, first time I did it, I pulled the wrong like from the cooler, the entire front end and my driveway got a nice coating of fluid. I made a real mess that day!