Pajero Owners Club of South Africa

I am a little concerned that something isnt 100% on my auto box.

Last week whilst braking the revs shot up to about 2500 for a few seconds before coming back to idle. Then yesterday following a gentle pull off the revs climbed well over 3000 and didnt change up, had to de-throttle and then it changed. Both times its been on a downhill gradient.

Also most times between 2nd & 3rd when driving gently it almost gives a 'slipped clutch' sound before changing.

Perhaps im being oversensitive, but if this isnt right then is it 1) the gearbox ecu / switch etc or 2) the A/T gearbox oils should be changed?

Thanks!

I don't think you have a problem. My Paj does it aswell. The box seems to be programmed to sence when the car goes downhill and then it shifts down or delays shifting up to assist with the braking under certain specific circumstances. Nothing to worry about, just get used to it.

going downhill the gearbox senses whether you want to accelerate or not
If not, it will keep a gear to 'brake' or keep the speed steady

Like the other guys said: The aotobox on the Gen3 has "gradient logic" and it sounds like that is what you are describing. The 'box is trying to help you.

Hi Gerrit,

Is there any way that you are aware of to disable the "gradient logic"? I find it a bit annoying and it spoils an otherwise brilliant setup.

I have resorted to driving in manual mode whenever the gearbox gets into one of its moods

Thanks
Bruce

Biggish,
Yip, shifting to manual is the answer. I eventually got so well trained by the car, that I would slip it into manual even before it could change down.

This symptom is gratefully not evident in my 3.8V6, thank goodness. I do not know if all V6's are like mine. Maybe the other V6 guys can comment.
Roelf

Biggish wrote:Is there any way that you are aware of to disable the "gradient logic"? I find it a bit annoying and it spoils an otherwise brilliant setup.

No, I don't know whether it can be de-activated. I quite enjoy it and would not want to turn it off. What irritates you? Perhaps it is actually the "fuzzy logic" adaptive shifting that irritates you: The 'box adapts its shift pattern to your driving style. If you drive in a relaxed fashion, up changes will appear earlier. If you suddenly start standing on the loud pedal a little harder, the 'box will soon adapt and start moving the shift points to higher engine speeds. It automatically does what the older 'boxes used to allow the driver to do via switches to select "Power" or "Economy" modes.

Hi

Went to Hoedspruit over the long weekend. For people unfamiliar with the road from Pta to Hoedspruit, it includes a long and steep mountain crossing and plenty of downhill bends.

I enjoyed the gradient logic a lot. I kept an eye on the vehicle in front of me, I almost used my brakes halve the time he used his. This must be very good for the brakes system and also lessens the chances of brakes overheating and creating problems.

I just thought about this post as I was doing the downhill and decided to give my opinion.

Regards,

No arguing the point, it is a safety feature. I just found that there were times when it was not required and then I'll go to manual mode and be happy.

What I found was that it didn't happen in "cruise control" mode and my 3.8V6 doesn't do it either.

No, I don't know whether it can be de-activated. I quite enjoy it and would not want to turn it off. What irritates you? Perhaps it is actually the "fuzzy logic" adaptive shifting that irritates you: The 'box adapts its shift pattern to your driving style. If you drive in a relaxed fashion, up changes will appear earlier. If you suddenly start standing on the loud pedal a little harder, the 'box will soon adapt and start moving the shift points to higher engine speeds. It automatically does what the older 'boxes used to allow the driver to do via switches to select "Power" or "Economy" modes.

Hi Gerrit,

There are two aspects of the auto box that irritate me.

1) It's the inconsistent manner in which the box reacts that I don't like. I understand that it tries to think ahead based on the drivers "mood" but it doesn't always get it right. This is however a small issue and I made peace with it long ago.

2) This is my primary complaint and hence my question around disabling the gradient logic aspect of the box.
I find that on gradients, both up & down, the box has an affinity for third gear. I'll try to explain:-

Uphills - pulling off on an uphill the box changes from first to second to third smoothly and at what I would consider to be the appropriate revs. Then it hangs onto third gear, sometimes up to as high as 4000rpm if I let it! That's when I get the zig and move into manual mode as I hate to see a diesel rev that high.

Downhills - on my way to work in the mornings I travel slowly down a winding hill due to traffic congestion. After the twisty bits, but before the bottom of the hill, the traffic flow tends to speed up but the auto box on my Paj became fond of third gear during the slow stuff and for some reason holds third for an unreasonable amount of time. It sometimes even continues holding onto third if I release the throttle. If I leave it in auto mode (against my better judgement due to the excessive revs it will go to) it will eventually select fourth and then immediately change to fifth.

To put the above two gradient related scenarios into perspective, it's not due to heavy acceleration that the gearchanges are delayed - in fact it's more prone to doing this when trying to drive economically. If I drive with more gusto the problem is less prone to occur. It also doesn't happen all the time - just enough to irritate.

The local dealers have been more than accommodating in trying to rectify the "problem". They have gone so far as to replace the gearbox control unit, flush & replace ATF, check diagnostics and finally they lent me another Pajero for a week (which did the same). Together we've come to the conclusion that there is no fault with the vehicle whatsoever, it's a combination of the fuzzy logic's interpretation of my inputs, the sensors (gradient, etc) combined with whatever happened during the previous five gearchanges that leads to it sometimes not doing what I would expect.
So we agreed that I am just a problem customer

So that's my story in a nutshell and I hope that explains why I asked if the gradient logic could be disabled.
I like my Pajero but I would love it with a manual box. I get jealous when I read the Ausie forums and realise that they can still get the manual versions.

Cheers
Bruce