Had a thread started and cant find it now...in a nutshell, wont shift into 4th gear. Changed fluid / filter and flushed system with about 4 gallons of fluid by removing return tranny line at the transmission case until it was crystal red. Drove fine for about 20 miles in 4th gear then downshifted itself and now all gears work fine except wont shift into 4th.

 

Was it having problems before fluid change? XYZ switch gone bonkers?

 

Yes before fluid change no 4th. Whats an xyz switch pardon my ignorance.

 

How many miles on it and what are your fault code numbers?

 

Was getting p0734 so replaced maf sensor did my fluid change as explained. Now just checked and getting a p0102.

 

And a p1884

 

Sorry 83000 miles....

 

no flashing m+s lights?

 

XYZ switch is on side of tranny, tells tranny computer the position of the gear shift lever.

 

No flashing m-s lights...btw it will shift into 4th downhill or when under a no load condition. As soon as gas or load applied it downshifts into 3.