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Discussion Starter · #1 ·
Long story short I went to goose the throttle through a corner and almost immediately after the 2-1 kick down she dropped out of gear and revved like she was in neutral while still being in drive.

The car will not shift into any gear and there is an audible whine. When dropping the selector into a gear there is the sense the transmission is trying to engage the clutches but there is zero movement or positive feedback that it has done so. I say there is the sense its trying to do something because there is a slight rpm drop that quickly recovers. Ive also checked shifter linkages and the shift selector switch for damage or play.

I dropped the pan and found a rather worrying amount of metal flake and buildup on the magnets. Im kinda devastated but it was bound to happen, shes endured 200K miles of abuse at the hands of me. I knew it was time for a fluid and filter change, I even ordered a transgo shift kit so I could buy more time to line up a decent replacement. But alas.

Motor vehicle Gas Auto part Metal Household hardware

I pushed some of the buildup to the side to give an idea of how thick it is. The center of the magnet is also packed.
Blue Hood Eyelash Automotive tire Purple

While I dont have a pic of the filter it looked relatively clean.
Motor vehicle Hood Gas Automotive wheel system Automotive tire

Liquid Cutlery Kitchen utensil Electric blue Close-up

Trans fluid that was drained (40K miles) vs New
Tableware Liquid Drinkware Cocktail Grape juice


While this is all pointing towards something very serious I want to bounce some questions off the community seeing as its a holiday weekend and Ive got nothing but time to try and revive her at least temporarily.

First Id like to ask if anyone has experienced this failure mode before and if so what was the fix?

What does this look like to you guys? ( My personal feeling is the 1st gear clutch is BURNT, my father on the other hand put up some arguments in favor of valve body issues)

IF my fathers line of reasoning is correct I already have a transgo shift kit on hand, would it be worth it to install even as a diagnostic measure?

Keeping in mind this trans has 289K total miles on it, is the amount of metal flake and buildup on the magnets normal for the mileage or is it indicative of something being so badly worn it needs replacement? (This is the first time ive dropped the trans pan so I have no reference as to the amount of time vs amount of buildup prior.)

I am open to any suggestions or advice.

Thank You.
 

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Recovering BDSO
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Discussion Starter · #2 ·
Welp, to answer all of my own questions, something definitely grenaded inside the trans. Got her to a shop for a rebuild and the mechanic said as soon as he saw the amount of metal flake inside the converter he knew everything inside was pretty much trashed. I also asked him about the build up on the magnets, he referred to the build up as being 10ft deep and there is no way there would be that much if the trans was salvageable.

Lucky for me these RE4's are this guys bread and butter, or they were in their hayday. He pulled a much lower mileage trans and rebuilt it for no extra cost.

End result, I have NEVER felt this car shift and accelerate as well as it does now. What a treat! I should have bit the bullet and had it rebuilt years ago!
 

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Change that oil regularly, autos are not as forgiving as manuals which most of us have on here.
 

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Discussion Starter · #4 ·
Change that oil regularly, autos are not as forgiving as manuals which most of us have on here.
Ive been on a 40K trans fluid change schedule for at least the last 100K-ish miles. Im not seeing a recommended mileage to change fluid at in the FSM. Got any suggestions?
 

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Look in the "Maintenence" section of the fsm though all I saw was inspect... and a sample to a lab, I don't know as I was making more of a generic statement.
 

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Discussion Starter · #6 ·
The maxima forums seem to have more auto guys talking about trans maintenance since we share the RE4FO4B's.

From what I've read the general consensus is to avoid doing a trans flush, instead do 3 separate fluid exchanges over a short time to achieve something like 80-90% new fluid in the trans at the end of it all. Mileage recommendations varied but 30-40K was a recurring number. I would shoot for 30K. As for the the time frame for doing all three exchanges it seems like most guys were doing this within a day or two max. I'd probably do all three within the same day.

Another suggestion I saw that I really like is exchanging 4 quarts ( or whatever you can drain from the pan) every 15K. Seems reasonable and will keep plenty of healthy oil cycling, can keep a better eye on how the oil and internals are wearing too.

Food for thought for the auto guys here.
 
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