Thread: Fix For P1811?

Document ID: 2323213
#09-07-30-013A: Intermittent Harsh Upshifts or Downshifts, DTC P1811 (Maximum Adapt and Long Shift) (Reprogram TCM) - (Aug 6, 2009)

Subject: Intermittent Harsh Upshifts or Downshifts, DTC P1811 (Maximum Adapt and Long Shift) (Reprogram TCM)
Models: 2005-2008 Buick LaCrosse/Allure
Equipped with 3.6L Engine (RPO LY7) and 4T65 Automatic Transmission (RPO M15)
2007 Buick Terraza
2007-2009 Chevrolet Uplander
2007-2009 Pontiac Montana
2007 Saturn Relay
Equipped with 4T65 Automatic Transmission (RPO M15 or M76)

This bulletin is being revised to change the labor time information. Please discard Corporate Bulletin Number 09-07-30-013 (Section 07 - Transmission/Transaxle).

Condition

Some customers may comment on harsh or firm upshifts or downshifts. These conditions may be intermittent. Diagnosis may indicate that DTC P1811 (Maximum Adapt and Long Shift) has been set. This condition may also include intermittent harsh upshifts at low speeds when lifting out of throttle, and harsh downshifts at 2-1 coast down, or harsh shifts when rolling to a stop and stepping into the throttle before completely stopped.

Cause

These conditions may be caused by the TCM setting a DTC P1811. This may not be observable on the Tech 2®. With a P1811, the SES light is not illuminated, but the transmission defaults to maximum line pressure. While the code is active and at maximum line pressure, all shifts may be harsh including upshifts, downshifts and shifts out of PARK. When the code is not active, most shifts may seem normal. However, the customer may comment on intermittent harsh upshifts and harsh downshifts, and a delay with harsh shifts when rolling to a stop and stepping into throttle before completely stopped.

Correction

An updated TCM calibration has been developed to address this condition. If the Service Information for the conditions described above do not isolate a fault, reprogram the TCM with the latest calibration available. Verify that the multiple diagnostic interface (MDI) that is being used is configured to the PC that will be used.

Important: Confirm the newest calibration includes the following description: "Select this calibration only to address DTC P1811 (Maximum Adapt and Long Shift), Harsh Upshifts, or Downshifts." This calibration should only be used to repair vehicles that have the subject condition. This calibration, or any that follow, is designed to address this concern. Use of this calibration to attempt to fix other conditions will not be successful and are subject to warranty claim review.

Note: Reprogram the TCM with the software now available in the TIS2WEB using the Service Programming System (SPS). If you cannot access the calibration, call the Techline Customer Support Center at 1-800-828-6860 (English) or 1-800-503-3222 (French) and it will be provided. As always, make sure your Tech 2® Diagnostic Scan Tool is updated with the latest software version. Clear any codes and verify the condition has been fixed.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

K9535

Transmission Control Module Transmission Reprogramming with SPS

0.4 hr

I get the occasional (2-3 times a month) p1811. Even though the 04 GP is not listed in the bulletin, the symptoms and transmission model are the same. Would this fix my issue without needing a PC solenoid or shift kit?

I know Im out of warranty, but if it only takes .4 hours, i would gladly pay the going labor rate.

Shift kits work aswell.

The best bandaid out there is a transgo shift kit and one bottle of lucas stop slip.

considering the fact that I do not have a lift, the tools, the time, or the knowhow to install a shift kit, and the fact that no shop in my area wants to do it, i figured this might be an idea.

can you follow directions?

if so you can buy a less then 30 dollar socket set that you get to keep. then all you need is a pair of car ramps and a drain pan of some sort. (someone you know owns these, borrow them)

theres a few how to's for the shift kits, lots of pics. and you get to service the tranny while your at it.

with all due respect.

all I wanted to know was if the above-referenced service bulletin would apply to my vehicle. a simple "yes it does" or "no it doesnt" was all that was necessary. Now i remember why I quit coming here in the first place. Whenever I would ask a simple question, i either got ducked or jumped on. I am not asking anyone to explain the theory of relativity, or the origin of human life, I am asking if a service bulletin can be applied to an unlisted vehicle.

When a line in my first post reads: "Would this fix my issue without needing a PC solenoid or shift kit?" and the first response I receive is: "Shift kits work aswell." I find it highly counterproductive and disrespectful.


SMH

Sorry.. guess I missed your typing at the bottom.

It's worth a try. I doubt it'll fix it honestly. There's a couple things going on in these transmissions that cause the issue. First is that GM left a lot of slop in the clutch baskets which make it take longer to engage. The other is that the pressure control soleniod has issues. Combine the two and you get low pressure that takes longer to accumulate and then a further engagement with sloppy clutches.

Tech bulletins, if the customer says something are fixed for free. I'd say give it a try. Sounds like you can't do anything else but rebuild otherwise from the sound of your post.

As for being disrespectful, there was none meant or given. You unfortunately got three guys trying to help you for free that read too fast and missed your question. Disrespectful would have been if someone said, " dude, can't you loosen a bolt?" That's disrespectful.