Citroen XM Forum

Bear in mind the autobox doesn't have any cooling when in Neutral, if I'm not mistaken. So too long periods of time having the engine idle and in neutral. For me it's easy, the car will roll back somewhat at home, if not in P.

Some have oil coolers don't they. Mine does as it has the little radiator behind all the others.

So is that right, don't leave it in neutral for long periods or it will over heat. Hmmmm..I tend to pop it into neutral if waiting at the lights for example.

I think else where there was an ongoing discussion on wether to pop into neutral or leave it in D when waiting at lights ect.

How is the box not cooled when in neutral, the oil pump is still running as it's driven off the input shaft?

The only time the pump isn't running is with the engine off.
The heat comes from the torque converter absorbing the engine torque, so in neutral there is no heat as both sides of the TC turn together.

According to what I learned (from a citroen mechanic) does the pump not run.
However this is not true, I just re read a big topic about engaging N or D at traffic lights and the chief mechanic was wrong, for once.

Confusing in the story is, that citroen advises to keep the car in D when at a stand still and also the zF factory documentation apparently clearly state that D should be engaged rather than going back to N. This causes quite considerable stress on the components.

So I was wrong but forgive me, but even a citroen chief mechanic had been under the impression until recently, that the box would not be cooled. This was the reason I took his knowledge for true.

It is better to keep an auto box in D when stationery to save wear on the clutches as they are disengaged then re-engaged.

I do it on the very slightest of inclines Russ, like the one on my drive. I know if the car is in N and there's no binding at all it will very slowly and very gently roll a little backwards. With foot brake on, engage P and then release the brake. If all is good the car will gently roll onto the parking pawl.

Generally if I'm stopped at traffic lights I'll knock the box into N as I detest brake light dazzle from others resting on the brakes at lights. I hate it so I don't do it myself..

The wear on clutches between N and D is infinitesimal Will. On the HP 20 the only difference between N and D (first ) when stationary is the engagement of one clutch. The other clutches needed for first gear are already engaged in N ready for an anticipated engagement of D. Can't say if that applies to the HP18 but I'd have thought so...

You wear the clutches far more going up and down the gears in normal use than you ever would by slipping into N at the lights!

In fact you're wasting petrol in D at lights because of the TC drag...

Jaap. I confirm the autobox is receiving full lubrication so long as the engine is running whatever gear is selected..

Excellent service from CPC Electronics yesterday. I ordered some MJ11015 blower transistors to replace stock used and they sent the the wrong transistors. One phone call and it was all resolved. They even said keep the wrong ones as the cost of returning them is not economic. Not bad at all!

Phew! Not doing it completely wrong then.
My only gripe, I wish the change up to 3rd would happen a lot quicker. Nothing wrong I might add, just a typical Change point. Yesterday for example, just got into third, and the old dear in a Honda Jazz up front ....doing exactly 28mph, and holding the traffic up, kept causing the autobox to change down. Most frustrating.

Any mention of a manual will fall on deaf ears!

russ92xmsed wrote: My only gripe, I wish the change up to 3rd would happen a lot quicker. Nothing wrong I might add, just a typical Change point. Yesterday for example, just got into third, and the old dear in a Honda Jazz up front ....doing exactly 28mph, and holding the traffic up, kept causing the autobox to change down. Most frustrating.

The holding low gears and additional noise it creates are the reasons I don't run Auto XM, TD.

russ92xmsed wrote:kept causing the autobox to change down. Most frustrating.

That's one good thing about an auto-adaptive like the HP20. It learns about old dears in Honda Jazzs' and knows to change up into top and stay there despite the snail's pace of the wretched thing in front...

So that would see off one of your objections Will

russ92xmsed wrote: Any mention of a manual will fall on deaf ears!

Quite. I just wouldn't entertain one now although I do keep one manual car so I don't forget how to drive one...

CitroJim wrote:

russ92xmsed wrote:kept causing the autobox to change down. Most frustrating.

That's one good thing about an auto-adaptive like the HP20. It learns about old dears in Honda Jazzs' and knows to change up into top and stay there despite the snail's pace of the wretched thing in front...

So that would see off one of your objections Will

My other car is fully adaptive, changes up at 1500 revs and holds the highest gear until performance is called for. Like all electronic boxes, it then takes too long to select lower gears on kickdown.