4T65E Trans Shift Hard, P1811 DTC

[012620]

Howdy BNaylor,

Thanks to your posts and all the other mods this is a website I always look at for info on my Buick Park Avenue and my Nissan Frontier Truck.

Can you give us a update on the three Buick test cars that you added a shift kit to the autotransaxle. Is the hard shifting issues still under control?

I have a 2000 PA with 47000 miles that just started the hard shift. Only has done it once. The trans fluid was changed at 19000 miles in Sept 06. I thought I would go to a trans shop and have them check for the P1811 code.

I also had a 2000 Century with the same problem. But I did not do anything about the problem for maybe six months. It ended up costing many $$$ to replace PCS and add shift kit. I don't want to wait very long this time if the shift kit might help. I also read that one should use Seafoam to clean out the trans.

Thanks again for all the help the mods do on this website.

[kgstrap]

We own a 2000 Chevy Venture (102,000 miles) for 5 years now that started a real hard transmission shift about 2 years ago. Took it to a transmission specialist and of course needed a total rebuild at 1800 +$. We started driving another car and basically parked the Venture. Recently I had to put the Venture back into full time service and started researching the trans shift issue and P01811 code. The symptoms were the same as many with these transmissions..hard shifting ...whining pump...sometimes just fine. It seemed logical that the computer was timing the shift and determining a fault followed by an action to max out pressure which in turn causes a hard shift. So just before a family vacation I decided to install a TransGo shift kit and replace the fluid with Dextron VI. After which I drove the car on Vacation totaling around 600 miles...And wow...so far it is great ! Shifting is a little faster, as expected, but no more clunk and clank. The transgo shift kit isnt the least expensive manufacturer but they seemed to have many praises. I spent around $100 for the total job..including Dextron VI fluid. I want to say thanks for the information and I will Keep you posted of the performance.

[HotZ28]

Recent technical bulletin from ATP Inc See bulletin; 09-08 Automatic Transmission Pressure Switch Manifolds.

[Rsajmiera]

I have a ? for kgstrap....I have a 2000 Pontiac Montana with the same problem. When you added the shift kit, do you only have to remove the bottom transmission pan or did you have to remove the large cover on the back. If you have to remove the large cover it looks like a difficult project. Also, which shift kit did you buy because some of them say they do not come with gaskets? I have added many shift kits, but never in a minivan!

[BNaylor]

Originally Posted by Rsajmiera

I have a ? for kgstrap....I have a 2000 Pontiac Montana with the same problem. When you added the shift kit, do you only have to remove the bottom transmission pan or did you have to remove the large cover on the back. If you have to remove the large cover it looks like a difficult project. Also, which shift kit did you buy because some of them say they do not come with gaskets? I have added many shift kits, but never in a minivan!

Just the bottom pan. You will be removing the 1-2 and 2-3 shift accumulator only to add the shift kit spacers. See pic.

And welcome to AF.

[RED REGAL]

Hi I realize this thread is old but I have 2000 Regal with the long shift code .I just read this thread and I have a couple of questions ?After you install the shift kit do you scan have code removed or leave the active code?Next question is the shift kit special for cars with long shift problems or will any shift kit work ?Changed tranny fluid twice,had code cleared lasted for about one hour plan to install shift kit myself.Wife`s Car

[maxwedge]

The pwm solenoid is the usual cause for high line pressure, so will this " kit" fix this?

[BNaylor]

Originally Posted by RED REGAL

Hi I realize this thread is old but I have 2000 Regal with the long shift code .I just read this thread and I have a couple of questions ?After you install the shift kit do you scan have code removed or leave the active code?Next question is the shift kit special for cars with long shift problems or will any shift kit work ?Changed tranny fluid twice,had code cleared lasted for about one hour plan to install shift kit myself.Wife`s Car

No issue with being an old thread. Welcome to AF.

The DTC will clear itself after a few drive cycles or you can discconnect the battery negative cable for a few hours. Also, this will clear the TAPS info stored in the PCM module so it can re-learn shifting patterns and your driving habits.

You can use the shift kits from ZZP, Thrasher, Transgo, etc. Some have the accumulator springs and gaskets in addition to the spacers.

Originally Posted by maxwedge

The pwm solenoid is the usual cause for high line pressure, so will this " kit" fix this?

(maxwedge) Shep, not all P1811 DTCs are caused by the pressure control solenoid (PCS). It could be mechanical wear, internal hydraulic issue, clutch pack, etc. Also, even if a PCS is replaced many get the P1811 DTC all over again which is frustrating.

[RED REGAL]

• Thank you on the welcome, I`am impressed on how quickly I got a answer one of those manufacturer of these kits must me available in Canada.The local transmission shop quoted me $2800 with a 2 yr warrantyThis is a great site and keep up the good work.

[enslow]

Originally Posted by RED REGAL

• Thank you on the welcome, I`am impressed on how quickly I got a answer one of those manufacturer of these kits must me available in Canada.The local transmission shop quoted me $2800 with a 2 yr warrantyThis is a great site and keep up the good work.

It's pretty hard to get stuff like that here, I have found. I got mine from http://www.transmissionpartsusa.com/

Make sure they send it through USPS and NOT UPS. UPS will charge you $20 brokerage fees, $10 taxes and other fees. Canada Post will charge you just $5 clearance charges + any taxes.

[RED REGAL]

Well its Saturday morning,I got a transgo shift kit and some dextron VI I`am going to install the kit.The kit didn`t really come with instructions but there is a paper with a picture,showing the accumulator and springs.It appears there must me 2 extra springs one red,one yellow that are not used?I will install the 5 other one`s and see how it works.Does anyone know if this will also help with the torque staying locked at hiway speeds? Before it keep unlocking even when pushing the gas pedal lightly.Forgot to mention its only 39F outside working in my driveway.

[DanOttawa]

Hello Red Regal. I'm in Ottawa too (Bank/Hunt Club area). How cool is that. I have a 2004 Chevy Venture (4t65e) that shifts hard and has code P1811. Mister Transmission wanted to put in a rebuilt for $2700 without really doing a proper diagnosis. B&N was a little more upfront with me, but again cant seem to find someone to pinpoint the problem. No one mentioned trying a shift kit until I happen to call a Tranny shop in Toronto. Then I stumbled on this site. Lot of great info here. Many thanks to BNaylor for all the great info.
Where did you buy your shift kit. So far I tried Partsource but they never heard of it. I'm not sure if I want to try this myself or find a tranny shop that will do it.

[RED REGAL]

Hi Danottawa I`am in the Vanier area picked my kit at Ontario automatic but they really try ed to get rebuild it completely.Read this thread right from the beginning

[DanOttawa]

Hi Regal. I know what you mean. The same with Mister Transmission. My Venture has 114000 km on it. All they wanted to do was sell me their rebuilt sitting on the shelf. Keep me posted on how your install goes.
Also the tranny shop in Toronto mentioned to reset the adapts once the install is done. I'm not sure what that means but thought it might be useful. Do you have contact info for Ontario Automatic.

[RED REGAL]

Good morning its Sunday and I installed the shift kit yesterday.everything went smoothly but its a messy job,hint don`t take the accumulator apart on the kitchen table you will get yelled at!The car shifts excellent from 1st to 2nd,2nd to 3rd also great but overdrive is still jumping.I know the kit doesn`t claim to fix overdrive problem,but I was hoping.When I took car on to the hiway and held the pedal down car shifted great but when engine got over 4000rpm it started missing and backfiring thru intake also check engine started flashing then light went off.I suspect maybe bad gas I`am going put some gasoline antifreeze maybe water in the gas.any suggestions appreciated!