AL4 Automatic Gearbox

[Nexus]

Now that my 1.6 automatic is on 97.5k (covered 40k in five years) I've decided to go through with a full transmission fluid change. This thread is essentially to document my symptoms, findings, experience with Peugeot and ultimately the final outcome on the box itself post fluid change.

I've been doing plenty of reading about the AL4 gearbox which is fitted to TU engined Peugeot and Citroen vehicles - But please do read through information online very thoroughly before undertaking any work on your own vehicle - Pinch of salt and all that! Here some symptoms I've been suffering recently which I feel relate specifically to the AL4 gearbox:

• On a cold engine, 1st gear hangs for a while before a harsh shift up to 2nd (hanging can be intentional to warm the engine quicker but should be smooth)
  
• Even on a warm engine, sitting in traffic 1st to 2nd, then 2nd down to 1st clunky
  
• Temporary, complete lose of speedometer when coolant gauge reaches roughly 70c. Speedometer reading returns after 1-2mins, occurs daily.
  
• With car in P or N, shifting to D or R takes a few seconds. Maybe followed by humming noise while stationary in D or R (Hydraulic pump).
  
• The obvious one: Sport & Snow icons both flashing simultaneously when ignition switched on. This is the Fluid Wear Counter or Check/Replace Fluid warning.
  

With these issues in mind, quite frankly I have never had the transmission fluid level or condition checked. I am hoping that the majority of the issues above are a cause of low transmission fluid or just simply old fluid that needs replacing. I did at one point attempt to replace my speedo sensor on the gearbox and this gave me a little peek at the color of the transmission fluid which to me personally looked fine. A sweet, candy red colour, unburnt. The sensor itself seems to be fine, which then got me thinking about the actual fluid level itself.

So I'll be taking the Estate to a Peugeot dealer next week for a diagnostic on the box to see exactly how it is holding up in its current condition, then a fluid level check and then finally a full fluid flush. If you are attempting to change the fluid at home you'll only be able to change roughly 2-2.5 litres at a time as the majority of it is held within the Torque Converter. The dealer should be able to use a vacuum system in order to perform a 90%+ flush.

I have read that early type AL4 gearboxes were pretty dire and that this was due to the solenoids and/or pressure regulators on the valve block. There was a revised regulator and solenoid released which can be changed over and then Ecu updated accordingly. This apparently had a good positive effect. Getting Peugeot to perform a diagnostic I am hoping that they will be able to give me a picture of whether this upgrade/fix is required.

So a few facts for you:

• SPORT & SNOW flashing simultaneously on the dashboard is a warning to check or change your transmission fluid.
  
• AL4 Gearbox must only take Esso LT71141 Fluid. DO NOT use Dexron type fluids.
  
• Esso LT71141 is a stock item and can still be bought off the shelf at your Peugeot dealer at £12.91 +Vat per 1ltr bottle. (I'll post the part number shortly)
  
• Gearbox valve block may also benefit from a solenoid and/or pressure regulator change. Only the two solenoids at the top of the valve block are affected. About £65 each if I recall.
  

Once I have a report on the condition on my gearbox I'll post an update - At the moment I don't think there is anything on 306oc for Automatics. Gti Fanboys!