Tranny maintenance after sitting for 2 years?

[ranger7ltr]

Hi everyone. I just bought a 1999 Explorer sport with the 4.0 liter OHV and automatic...I decided to see if the original engine ran and with an oil pump and pan cleaning I now have great oil pressure and a seemingly solid 4 liter engine..And it has 155k on it as well...

The tranny I am needing advice on though...This vehicle has been sitting for a while and the fluids are old and need replacement...I removed 4 liters of fluid from the tranny and reinstalled new fluid just to prepare to drain and drop the pan and the cooler lines...

I drove the vehicle after tranny fluid top off and it seems to flare on the 2-3 shift... But I also cannot get the O/D light to come on when I push the button in the end of the shifter...The tranny seems to go into o/d as I am getting up to 60-65 mph and the revs are under or around 2k....The fluid flush I think is the next step in this process and I have found some issues on the 2-3 flare with the EPC solenoid replacement and possible vb rebuild/replacement...

Does anyone have any tips on what else I should be doing with this tranny before I do a full shakedown run and see if the tranny will hold up or not? I bought this truck to do a V8 conversion but I am finding that lack of maintenance primarily is what killed this truck in the first place...

Thanks in advance...

 

[BrooklynBay]

Start with a fluid & filter replacement before you change any parts.

 

['97 V8]

fluid and filter change. Remove the inspection pan and drain the torque convertor as well.

 

[BrooklynBay]

The 5R55E doesn't have a drain plug on the torque converter.

 

[ranger7ltr]

Draining the tranny...

Can I drain or flush the torque convertor by opening the cooler lines and running the engine as I add fluid by to the tranny?

And I believe the OD switch is working as I saw the revs increase when I pressed the button while driving about 50-60 mph and not accelerating...

Can the light in the shifter be replaced if it is blown out?