Shifting Problems

I have a 2000 Grand Cherokee Ltd 4x4 4.7L V8 w/ 80,000 mi. My problem seems to be "bump shifting" when I'm at speed and I decelerate then accelerate my car bumps like it is shifting rough but I'm not sure if it is even shifting. It may be dropping and then shifting up very quickly. This happens on a regular basis.

Also when I'm idling around a parking lot sometimes it feels like someone hits me from behind. This happens about once a week or so.

My rpm also jump around without pushing the gas. Sometimes it will idle down very low when I'm at a stop light or sometimes it will idle up when I'm parking the car and it is going from D to P or vise versa.

I have recently had the ide airspeed motor replaced and the tps replaced. This only helped a problem where my car would idle up to about 3000 on startup and then bounce down to normal idle reving up and down as it went.

What are some things I should check?

Welcome to AF jestawa

Have you checked for failure codes yet. That should be the first thing.

JD

Yeah, It's one of those things that is hard to replicate and it's not coding anything.

I went thru the gears manually and it seems like all the trouble is in second. Whether it is getting into, out of, or driving in 2nd. It bumps going in and out of 2nd and it has a hiccup while driving in second.

I found some info on retraining chrystler transmissions. Do you think that could be the problem?

Any ideas would be greatly appreciated.

Might be a retraining problem..

Has the fluid been changed lately? what fluid are you using?

Was any other work done to the Jeep around the time this started happening? Any accidents?

JD

No accidents. My battery died a while back and I had to get a new one. Can't say that I remember if the problem became noticable before or after that. The worst thing was the irregular idling problem. When I saw the retraining plan it says to disconnect the battery so I figured that mabye when my battery died it reset the computer and I didn't properly train the trans. The only thing is that the problem is mostly around 2nd gear.

I had the 60,000 mile service done at around 70,000 mi and they said there was nothing dirty or odd with the trans fluid. Not sure what type of fluid they used. It was done at the dealer so I would hope they got it right. I think ATF+3 is what is recommended. Is the wrong fluid a common occurance at shops?

Also I have recently replaced the fan clutch.

If the trany service was done at the dealer, I wold hope that they use the ATF+4 that is called for.

I would try the retraining as it is something you can do.

The second gear thing puzzles me too. I'm not sure what trany you have but some have a kickdown cable that can affect the 2nd gear shift in some ways. Again - not sure that it applies to your Jeep but you could look into it further.

If it doesn't have the kickdown cable there might be a connection to the idling problem. Maybe the throttle position sensor.. If you had the tools and a manual you could check it.

JD