DS5 auto box

[zipdip]

Hi all been awahile since I was posting on here,the DS5 has been behaving itself,well most of the time,I have been getting a jolt when I engage drive on my aisin auto box,it has been doing it for a couple of weeks,so I booked it into a Citroen garage about 10 miles away my nearest,for a auto box oil change the car has done 74grand,ok so two days after I booked it in for the oil change in a weeks time the jolt has disapeared,you could not make it up but it must need a oil change,does anybody have any idea what has caused this jolt.

One other minor propblem I would like help with is when I have done a fair biy of driving and I am waiting for lights to change with the car in drive and my foot on brake ,when I lift my foot of the brake the car does not move and then it jolts like the brake pads have held on and then suddenly come off,new discs and pads about 6 months ago.
Thanks for any help you can give.

[GiveMeABreak]

That's really quite a long time to wait before changing the oil gearbox to be honest. Despite DS / Citroen saying the boxes are 'sealed for life' in reality the oil degrades over time and becomes contaminated with clutch friction material and the oil also degrades during operation from high temperatures. The Gearbox ECU has an oil wear counter and over time it adjusts the operation of the gearbox to account for this.

The second issue is that you can't fully drain the gearbox oil as about a third of the oil remains in the torque converter after draining. So realistically, although better than not draining it at all, it will take about 3 complete draining and refilling operations to get as near as you can to a full change. Some leave this a thousand miles or so and then repeat the operation a few more times to get as near a complete flush as you can.

So one drain is not going to do it.

Take a look at this video - this is for the Aisin 6 speed and although it's a Volvo, the same gearbox is used by many manufacturers. It is very useful as he explains how the process works and shows you the oil quality form each drain at the end. He has opted to make the 3 changes in one session, by allowing the oil to run through the system with the engine running and changing through the gears to mix the old oil with the new, then drain again. As you can see it makes a big difference:



Whether changing it a few more times will stop the jolting noise in your case I can't say, as there may be something else causing this related to the hydraulic block.

One thing I will add is that he has not only removed the drain screw to do the job as is the official recommendation, but he has also removed the oil levelling bolt in order to get more of the old oil out of the gearbox. This will be more effective at getting rid of more of the older oil.

[zipdip]

Thanks Marc for the reply will give the video a look at,the garage said it is sealed for life,does not fill you with too much hope,but did tell him it needs doing and so will take it to them,any idea whats making the brakes holding on when you take your foot of the brake pedal,my passengers think its my bad driving but I give them fair warning as it is maybe 3/4 seconds before the joly.

[GiveMeABreak]

Well the vehicle has a hill start assist system that maintains pressure on the wheels via the ESP system for a few seconds, but it may be the brakes sticking on. This may be a caliper related issue. When was the brake fluid last changed? It's supposed to be replaced every 2 years.