Need trans help: bad clutch, leaky solenoid, or pressure too low?

The 1UZFE EGR Delete Kit is available for sale here.


1998 GS400, 205K miles, original drivetrain. No trouble codes. Trans fluid was pretty dark when I bought it, so I flushed it all out through the cooler lines. I also dropped the pan and turned the pressure dial to max.

So I’m still trying to figure out why my 1-2 upshift and 2-1 downshift are so smushy. I can’t feel any shift shock whatsoever no matter the throttle. All other gear changes seem ok.

I’ve been researching the crap out of the transmission function. Here’s what I’ve come up with so far:

I initially suspected the no2 shift solenoid, because the engagement into second gear is occasionally kind of jerky, more so when cold. However, downshifting from 3-2 also is kind of jerky sometimes, the shift solenoid 1 is what activates to control that shift.

maybe both solenoids 1 and 2 are sticking? Is it possible for solenoids to leak? That would cause issues without throwing codes.

But maybe since gear 2 is the only gear where both solenoids are active, the extra fluid paths are causing a loss of line pressure? That might mean the line pressure solenoid is bad.

maybs I’ll just say screw it all and put in a junkyard transmission. I can get an entire gearbox for the price of two damn solenoids.

Your help is greatly appreciated.