Here’s a mystery which as stumped several mechanics. I have a 1999 Jeep Grand Cherokee Laredo. Some of the gears are intermittently “sticking”. When I get up to 60 m.p.h., it’s supposed to shift into the next gear, but sometimes it won’t and the vehicle starts lurching as it comes up against the “shifting wall”. Other times it won’t downshift, so I leave a stop light in 2nd or 3rd gear. The lurching only occurs for the gear at about 60 m.p.h., unless I put the gear selector into “2”, then it sometimes lurches there too. Several mechanics, including a transmission specialist at a local Jeep dealership (who charged me for 2 hours of “diagnostic time”), couldn’t determine what is wrong. I did a transmission fluid flush, but that didn’t help. I’m at my wit’s end!