Trans slipping and downshifting hard

[TheManInBlack]

I have a 2004 gtp 95,000 miles. trans was slipping and downshifting hard, i changed the PCS and did a fluid and filter change, which didn't solve the problem. Took it to the dealership and they said i needed have the pcm updated so i go and pick it up and they said they updated the pcm and no more codes popped up and they also test drove it and they said it waas fixed.

It's not fixed, not even a little. Does anyone have any ideas? Also the tapshift and cruise control isn't working dont know if that can be tied in with the transmission problem? any advice would be great, thanks in advance.

Joe

[Scottydoggs]

if its under warranty take it back to the dealer, (if you have a warranty.) before you run out. if you have the 100,000 mile one.

trans work gets expensive real fast.

[dsmuts]

Car's 8 years old i'm thinking the warranty would already be expired.

[TheManInBlack]

yeah, it expired last year.

[TheManInBlack]

I've also taken it to the dealership to get the trans checked out twice.. getting impatient.

[Scottydoggs]

find a good local trans shop and have them scan it, no cel yet?

BTW dealers suck unless they are doing free work. stop paying them.

[TheManInBlack]

find a good local trans shop and have them scan it, no cel yet?

BTW dealers suck unless they are doing free work. stop paying them.

no engine light, and i've only payed the first diagnosis fee second time he didn't charge me.

[DruMor]

When you give it gas to downshift from OD to 3rd, does it gain several hundred RPM and slam into 3rd all at once? Does it upshift correctly?

[TheManInBlack]

When you give it gas to downshift from OD to 3rd, does it gain several hundred RPM and slam into 3rd all at once? Does it upshift correctly?

Well, once i take off and get up to speed (say 50mph) its fine. until i let off the gas completely it starts to downshift hard like you downshift with a manual trans. And when im goin about 30mph it hit the gas about 1/5 throttle it revs up to about 3000 rpm then slams into gear. I hope i answered that correctly..

[DruMor]

The part about when you go about 30MPH and give it gas and it revs and slams into gear sounds just like what my 2004 GTP (101000 miles) does as well. Mine doesnt downshift hard at zero throttle though. I too did the pan drop and new filter change with no result.

Following advice I got on here, I drained out a quart of trans fluid and added a quart of Lucus stop slip. It didnt completely fix it, but I definately think it helped, because it doesnt slam into gear nearly as violantly as before. Another post to my thread was from someone else with a '04 that their car did the same thing as mine and sounds like same as yours, and they added a shift kit and again, it helped but didnt fix it. I learned to drive mine to minimize downshifts and use Tapshift when I need to downshift, but it sounds like Tapshift isnt an option for you right now.

A couple weeks ago, I talked to a guy I know that owns a transmission shop; and he told me he worked on one that was doing this and the problem was a worn bore for a valve in the channel plate. But the way I understood him you pretty much have to have the whole trans apart to get to it.

[gtx3800]

Sounds like you should slap a new tranny in it, especially if your going to keep it awhile. Your not far from Ft Wayne, IN. Call/email Dave at TEP, he could let you know your options and a price. His website is informative and gives you prices as well. www.Tripleedgeperformance.com
I live near STL and I'm takin my trans up to him. I'm gettin a built trans installed for a few hundred bucks more than what shops around here want for a remaned ****ter. Just my .02