I have an 01 Jeed Grand Cherokee (WJ) with a 4.7 liter.

I noticed a year ago that my Jeep tried to downshift (violently) while I was cruising on the highway. I didn't have that problem with it again until recently, I noticed it downshifted and jumped right back in to top gear.

This last week I took off from a stop light and it jumped in to top gear (5th) and killed the engine. I slipped it in neutral and started it back up. No problems, I made it all the way in to work with out any problems.

I called up my local dealer and ordered up a couple of Vehicle Speed Sensors. I figured from what I had read about other people having trouble with sporatic shifts that must be whats wrong with mine.

I parked the Jeep and borrowed another vehicle for a couple of days, I finally get to work on it today (couldn't take off of work to do it...) I pulled the speed sensors out and notice a little bit of gray build up on the sensor close to the O-ring. It looked and felt like anit-seize.

I have had my Jeep since it was new, the transmission has never been abused and has never been apart. I installed the new vehicle speed sensors and took it for a quick test drive this up the road. No problems.

This afternoon I took off and made it several miles before I could get up the speed to get in to top gear. The first time it shifted in to top gear it wanted to shift right back down in to 4th and then jumped in to 5th. I slowed down and let it down shift in to 4th and tried to get it to do it again. From then on out it shifted in to 5th gear just fine.

I came to a stop at a stop light with heavy traffic, I got on it to make it through the intersection, it stumbled a little but but took off.

I stopped on a flat parking lot and checked the fluid again and found that it was at the correct level, the fluid was clear/redish tint, and no fowl or strong odor.

I want to say it has been a few years since it has had a new fluid and filter but I have been afraid of washing off the clutches with fresh fluid so... I have been reluctant to do it.

I was hoping that, since it SEEMED to be doing better that it was acclaimating itself to the new sensors but... that just because I am hoping that it isn't something much worse.

Any help or advice is greatly appreciated!

Was trans filter changed recently? Only real problems with the 545re are filters not sealing to the pump and valvebodys that explode.

Have you had it scanned to see if it set any codes or 1 trip failures ?? Sounds like it was going into limp in on you (second gear) which can be hard at 70 mph. Get it scanned and have the input and output sensors checked real close as it may just be one of them. Ron

No, I want to say the filter and fluid was chaged about 3 years back.

I have not had it scanned, would the transmission diagnostic codes be seperate from the OBD Codes the engine would trip? More specificly could the transmission trip a code and not illuminate the CEL?