a/t slips when shifting

So I've been fighting this problem since I bought the truck. It was like that when I bought it. Also the fluid was overfull before I drained it. Under any load conditions it'll slip shifting from 2-3. Most of the time it feels like 1-2 but it shifts from 1-2 before the speedo starts moving usually if you pay attention you'll feel it. The truck will go 1-2-3 before 15mph and lug up to speed in 3rd. I was given a new filter, gasket and fluid (correct fluid) when I bought it. I dropped the pan yesterday to find metal flakes in the pan. The only way to describe it was like a blowout near the hole in the valve body that the filter covers. It looks like something metal was sent down that tube and blew through the filter and hit the pan and kind of did a "splat" kind of effect that was about 3" in diameter. I know older autos the shavings are normal. It's uncommon not to have any. In newer cars the amount of metal would more than justify a replace. The filter was dirty but no metal. Magnet was full too. By the gaskets on the pan I know it's only been changed 2x in the truck's 200k miles. After changing it all the truck doesnt lug so bad but the quick 1-2-3 and slip from 2-3 is still there.
I read through the ESM diagnosis page. It only lists eratic shifting. And under that section pretty much everything is a culprit.
I'm wondering if there's any way around a rebuild/ replace. If I have to replace I'll swap in the 2.6 driveline from my first gen donor truck and convert it to 5-speed. Or will that trans bolt to the 2.4L?

Sounds like the clutch plate/bands could be bad, that would justify slipping between your gears. As far as early shifting couldn't tell you but with 200k i wouldn't be surprised if they went bad.

I'm not sure about these tranys but if there is a modulator I would change it. But slipping is a big problem. It can be old and dirty filter. I know on a regular trany they come in different ranges indicated by the color band.

I was thinking a piston in the valve body is getting stuck. Instead of dropping rpm on the shift it'll rev up maybe 500rpm before shiting into 3rd. Changing the fluid and filter seems to have helped a little but not much

Ya I'm not the guy to talk with on the autos on these trucks. But you can have a sticking valve.

me and my dad did some brainstorming with it and I think I'm going to tackle the kickdown linkage first. The linkage bushings are non existant so the linkage hangs in the holes and the cable is adjusted to max and still has alot of slack so I'm thinking get a new kickdown cable and bushings to start. That would explain the 1-2-3 shift so early and if it's under 15mph and low engine RPM there's not enough fluid PSI to strongly engage 3rd. If I floor it from 15 it'll kick down to 2nd and run strong to about 30 then shift firmly into 3rd but it only does this with a downshift not hard from a stop. I've gota fix that first.

There should be very little slack in that kickdown cable or you will have the strange shifting you are experiencing.

I got it taken care of today. I adjusted it at the throttle end. It shifts like it should now but I've still got the 2-3 slip but now at average throttle it doesnt kick in til maybe 25mph. I know I need to replace the bushings to get more responsive kick-down. I looked at my hydraulic circuit and the front servo is released going to 3rd which engages the front clutch for 3rd and O/D. The rear clutches are always engaged in Drive. If I can get my hands on an appropriate gauge I'm going to check front servo PSI at the service port and see if it's in spec. I have a feeling that servo is sticking which is similar to what camoit was saying. Just mitsu uses a different word for it. The book says before checking servo pressures make sure the kickdown linkage is adjusted properly so that's why I went for that before internal issues since I knew the bushings were shot and I wanted to try everything easy before considering going into the trans lol If the servo is just stuck and the spring isn't worn out I could most likely drive the crap out of it and make it start working again. Now that the kickdown is working properly, at slow speeds it shifts good but accelerating past 35 it'll slip when shifting and it gets worse the harder you push it.