Replacing AL4 ATF

Some ppl change their car ATF every year while others wait until their cars hit 30,000km mark on the clock. Local SC's recommend to do it every 60,000km.

For my 308 I prefer to wait until the ECU tells me when it is the right time to replace the ATF...

... and it happened after 5 years and clocking 71,000km... 

Click  HERE for reference.

Understanding Auto Adaptive Transmission

To get the best out of Peugeot 308 it is important to understand how the Auto Adaptive Transmission works;

...for fuel economy,


...or sprinting from 0~100km/hr under 9 seconds.

In a Conventional Auto Transmission, gear ratio changes are made when the specific operation condition of the transmission (accelerator pedal position, engine torque power etc.) are met.

Auto Adaptive Transmission is an extension to the control of changes of gear ratio of an automatic transmission programmed with distinct shifting rules, called variograms, applied according to the multi-variable input from operating conditions of the vehicle.

The Adaptive Transmission ECU studies driving behavior and then adjusts its workings to deliver “suitable” throttle response and “appropriate” shift points. To achieve this feat, there are multivariable inputs or modus operandi to be processed by the ECU. Needless to say, the AL4 transmission on Peugeot 308 relies entirely on sensors and computer controls.

Sensors will tell the ECU when the car’s going uphill, downhill, around a corner and even when the driver gets spirited. The ECU directs gear changes according to event-specific algorithms designed to make those experiences “better.”

Selecting 'S' mode [as i always do when got tired in TipTronic] calls-up a different internal 'map' or program which allows higher engine speeds during acceleration, and delivers more responsive downshifts when braking or/and slowing down.

Tell and Teach the AL4 computer the way u always want - either for better fuel consumption or performance. It's your choice.

The ECU constantly learn to ADAPT. But NEVER try to tell the ECU u want good fuel consumption while flooring the accelerator most of the time.

p/s On Peugeot 308 Auto; double d'clutching, heel n toe, pumping the accelerator techniques are not applicable. Pls unlearn all these. Once the ECU understands ur driving style just floor the accelerator or release it then brake whenever needed, let the ECU take care of everything except watch the direction u r going and steer accordingly..

Enjoy and Celebrate ur life!

Happy Motoring!

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AL4 Transmission is Lubricated for Life

The AL4 [autoadaptive automatic gearbox] is LUBRICATED FOR LIFE!. All that is required is an oil level check at 60,000 km . Despite that, the automatic gearbox has a system for measuring oil quality. Service Centers and ATF suppliers/agents/sellers recommending otherwise for obvious reasons.Now ask ourselves; "Has anyone ever mentioned to service and/or re-lubricate drive-shafts?" Drive-shafts take the most severe torture than anything else on a car yet don't require maintenance except when the boot are damaged/torn.

Nevertheless, the AL4 auto-adaptive automatic gearbox ECU has an oil wear sensor . For a given time interval, the counter increases by a certain number of units (of wear) depending on the temperature of the gearbox. When the counter is exhausted, the gearbox ECU informs the driver of the presence of a fault by the flashing of the "Sport" and "Snow" indicator lights on the instrument panel.

Using the diagnostic equipment, the mechanics will check whether or not it is necessary to replace the ATF. However, within warranty period one must obey the terms and conditions otherwise warranty void.

Besides Peugeots, AL4 Transmissions are also used on Citroen, Renault, Proton Waja, etc.. Read more about AL4 Transmission HERE

Get the FACTs not Myths....

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AL4 Automatic Transmission - Pressure Regulation Fault

I used to have a problem with my earlier Peugeot [not 308] AL4-Transmission. It was under warranty, so it didn't incur any direct cost to me except time, fuel and toll. But I learned quite a lot in return at no cost for consultation. I just want to share my own experience on the symptoms so that everyone will take immediate action before it is too late and start to make lots of noise in the AutoForum...

Symptoms
Flashing of the "Snow" or/and "Sports" light then the transmission went into the downgraded mode. In this mode the transmission was locked in third gear to enable to continue the operation of the vehicle following by a loss of power. The downgraded mode sometimes preceded by some very harsh [jerking] shifts. However after stopping and restarting the engine, the transmission would usually return to normal operation.

Most of the time the problem appears at unpredictable intervals. Some incidences were on a daily basis, sometimes may have weeks of trouble free operation between incidents.

What was logged in the ECU?
At SC I was told the following fault code was logged in the transmission ECU: "Intermittent fault. Pressure regulation fault, recommendation/variation"

Cause
Being a technical person I usually ask for the explanation. I was told the pressure regulation fault code was triggered when the ECU senses a difference between the calculated pressure and the actual line pressure in the transmission. The pressure difference was caused by internal leakage. Internal leaks could be caused by mechanical wear, a leak between valve body and transmission casing, incorrect adjustment of the manual valve index spring.

The most common cause however is the pressure regulation solenoid valve.

Diagnosis
The diagnosis was not straightforward, several operations were required to eliminate possibilities.

1. Transmission fluid
1. ATF level was checked in the transmission. [Note: Low or high fluid levels are equally harmful]
2. ATF was placed in a clean container for examination.

The transmission didn't need to be overhauled or replaced because the fluid sample was normal like fresh ATF, i.e transparent. Fluid drained from a transmission that has been in operation for some time is usually dark in colour and lacks transparency, this is acceptable and not necessarily an indication of an internal fault. Caution was exercised with the fluid assessment.

2. Pressure sensor
1. With help of the diagnostic computer the transmission line pressure was checked.
   The following parameters were observed.
   At idle in N around 2.6 bars.
   At idle in D around 3 bars.
   Under full load 2200 rpm: 11.5 bars.
2. Since there was change in pressures, no need to test the sensor and sensor supply.

Note: A faulty sensor maintain constant pressure of 6,5 bars. This would also mean that the transmission would be in Limp Home Mode and that the fault is permanent. Since the problem usually was intermittent the pressure readings would check out OK most of the time. Since no other problems have been found so far, diagnose continued...

3. Solenoid Valves
1. Pressure regulation valve and the converter lock-up valves were replaced.
2. 2 seals behind the valve body are correctly fitted. The seals were not replaced.
   
3. After fitting the valve body, the selector index spring was adjusted
   
4. The multi-function switch was also adjusted.
5. Before fitting the pan , the 2 magnets presence was assured.
6. ATF was refilled and adjusted the level.
7. The transmission ECU software was updated for the new solenoid valve because the older software versions are not compatible with the new Borg Warner valves.

The operations outlined obove resolved the pressure regulation problem.


If the problem couldn't be resolved Valve-body probably need to be replaced. Worse case, the whole Transmission required overhaul or replacement.

Important reminders to observe

1. Only use genuine Peugeot ATF.
2. The fluid level must be correct.
3. The correct adjustment of the manual valve index spring is very important.
4. Adjust the multi-function switch after the valve adjustment.
5. Cleanliness is absolutely essential when working on the transmission.
   

Is is good to know...

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