Hey all, after extensive TLC on my 98 4.0 auto xj, I've eliminated the the lockup code, it's driving great, however climbing up to Pollock pines yesterday I noticed after romping it up the steep hills at 70+ that it wasn't locking up in 4th anymore, but no code occurred. After shutting down, cooling of, and restarting, all was normal again. Cooler too inefficient?

 

It's electronically controlled.

How's the adjustment of the TCC switch up on the brake pedal?

 

Brand-new switch installed and adjusted properly , the symptom only revealed itself after hauling *** up a mountain stretch of highway 50 with steep inclines

 

Lock up solenoid heating up and failing?

 

Have wondered if that ultimately is the issue, however it not throwing a check engine light was kind of odd as in the past they were very quick to come on when it would not lock up

 

Oh yeah. You've got that new fangled crap.....