Mate

Good day gents,

My 1997 XJ has had a weird transmission issue since I first bought it two years ago. It had 425,000km on it then, and 450,000km on it now. It runs, drives and shifts really well for the mileage and torque converter lockup happens when it is supposed to.

Once the torque converter is locked up in OD, it stays locked unless I let off the gas, it dips below 900 rpm, or it downshifts (which I think is normal behaviour). The problem is about 90% of the times when it downshifts under load and the TC unlocks, it "forgets" how to lock up again and stays unlocked. Sometimes if I pull over, shut it off for a minute and start it back up again it "remembers". If not, it will work after being left overnight. Pulling the shifter down into "3" under load will result in the TC unlocking, downshifting, and then locking up again like normal. Once it's decided it doesn't want to lock after a forced downshift, it won't lockup in "3" either.

This recently happened to me at the beginning of a 5 hour hilly drive towing a 1600lb trailer and I almost fried the trans going up a big hill.

Any ideas? Anyone seen this before?

tech

To me it sounds like you have a TCC solenoid going bad .