transmission slip

[mash35231]

I bought a used 01 PT recently from the original owner. The previous owner never had the transmission fluid changed. After changing the filter and 4.5 qts of fluid the transmission is now slipping. It didn't slip before but the car has 130,000 miles on it so I decided to change the filter and fluid. My question is...why would it slip after changing the filter and 4.5 qts of fluid? Should I bite the bullet and go have a full flush done?

[Dino]

Originally Posted by mash35231

I bought a used 01 PT recently from the original owner. The previous owner never had the transmission fluid changed. After changing the filter and 4.5 qts of fluid the transmission is now slipping. It didn't slip before but the car has 130,000 miles on it so I decided to change the filter and fluid. My question is...why would it slip after changing the filter and 4.5 qts of fluid? Should I bite the bullet and go have a full flush done?

Their is two schools of thought in this, some believe that when a transmission gets that old its better to be left alone if it hasn't been maintained but since you already did it that really doesn't matter anymore. Also did you put the right fluid in? Only use ATF +4 a lot of places will tell you that the stuff they use is just as good but don't believe it.

[mash35231]

Yes it was ATF+4 fluid.

[mdfrodolives]

Mash, what do you mean when you say the trans is "slipping"? Perhaps the transmission is simply not shifting gears at the right time--as compared to the shifting sequence before you changed your fluid, that is.

Sometimes when the trans fluid is changed in a PT automatic, the transmission has to "relearn" itself. When the dealer changed mine, I drove it home and it didn't shift at the proper times. I brought it back and they had to "relearn" the transmission with a computer program. It took about five minutes for them to do this. After, the transmission shifted beautifully.

Tim

[heifetz17]

When a transmission isn't cared for like this one wasn't, the clutch packs inside start to wear a lot faster than they should. This causes particles and debris in the fluid. As the clutch packs wear to the point they can't function anymore, they've caused a very large amount of foreign matter in the fluid.

The clutch packs rely on these particles to supply the friction they need to still operate. When you replace the fluid and filter in a situation like this you lose the dirty fluid with particles in it, and replace it with clean, fresh fluid.

The clutch packs no longer have the help they need to still operate, and begin to slip. This is one of the most common causes for tranny failure.

I hate to say it, but I'd start looking at replacement trannys. In my experience, I don't think yours will last a whole lot longer.

[mash35231]

What I mean by slip is...Sometimes while waiting at a stop light/stop sign when I excelerate from a stop the transmission takes a couple seconds before the car moves....I hear and see the RPM's going up but the car doesn't move....it will move after a couple seconds but I've noticed it doesn't do this everytime I stop, just sometimes...and what is this "transmission needs to relearn"....that's a computer control of the transmission?

[CREWZIN]

Here's an older thread on the subject that might answer your question: (be sure to read both pages)

Transmission Relearn Process. How to Avoid it?

[mash35231]

Thanks Crewzin for the info link. There seems to be some "muddy water" on this subject. I'll wait and see if there is an improvement with my car.

[cruserdad1976]

Tranny Service is always a grey area but like already said and said verry well you already chnged it so you cant go back
I never had to deal with that relearn thing some dont belive it some will live and die by it I cant see how it can tell if the fluid is new or old btu ???

You could maybe try some kind of a additive to help soften the seals ir expand the O rings

heifetz17 is pretty much right on target id start looking at replacing that tranny

[heifetz17]

The information provided directly from Chrysler states that you should not need to relearn the transmission after a service. A relearn would not solve a problem like you just described.