1989 cressida GLX More questions

I am not familiar with the GLX trim level as it was not available in the U.S., but for U.S. models, the answers are yes to both questions for the automatic.

Just pulled sump off,oil slightly dark red some fine black probably magnetic dust in bottom round magnets. The fault codes are 62,63,64.(seem all the solenoids) All solenoids between 13 & 15 ohms, (book says 8 ohms)two normally closed one normally open,all function (open and close)with voltage supplied. Is gearbox all controlled from main ecu? I am having trouble tracing wiring and finding all connector block positions. The gearbox was functioning normally this day(apart from fore mentioned problem when cold)when it ceased to function at all As I mentioned previously it did it a month ago but started working after turning off then on again. Can it fail mechanically more or less instantaneously with no slipping or warning in the previous weeks)or am I looking for electrical problems, or oil blockages?

All gear positions are controlled from the main ECU, which controls the shift solenoids, which determine which gear.

If the gearbox acts up suddenly, the most likely cause is electrical, Mechanical failure usually gives warning like slippage.

If all three solenoids check out of specification, then all 3 probably need replacement. That will probably cure the problem.

The solenoids resistances are all within specs and function when energized, So I am running out of options.

As hachiroku suggested, check the resistance of the solenoids at the ECU and see if there is a significant difference from the resistance measured at the solenoid connectors. If there is a significant increase in resistance, the problem is with the wiring between the ECU and solenoids. Check for a damaged wire loom or a loose connector.

I think I have problems, today I reassembled with new filter, filled with oil and it now will move but it it seems to slip. I there a different clutch pack for reverse as reverse with the brake on won't rev much passed idle but forward will.Why does reverse not slip but forward does?

How hard is it to remove and replace box with car on stands? Can it be done with two stands (front only)?

With the transmission in drive or reverse and the service brake applied, the engine should rev to over 2,000 RPM. If the engine won't rev that high with the transmission engaged, line pressure is too low, a clutch is slipping, or engine power output is low.

I've never tried to replace a Cressida transmission on stands. I would want at least 4 stands so you have room to work and a place to rest the driveshaft. Note the orientation of the universal joints at the transmission and differential before you disconnect it from the transmission. If it is re-installed out -of phase, it can cause a vibration.