problem with overdrive

[SteveN]

Hi guys, well after nearly three years of trouble free motoring with my '95 mistral I have a niggly little intermittent problem with what seems to be the overdrive.

Sometimes when I'm driving as soon as I ease right off of the accelerator the autobox goes down a gear, a bit of putting at 60+ mph.

Is it a problem with the overdrive or just a case of replacing gearbox oil ?

Any ideas ?

cheers
Steve

 

[(RIP) PLANK]

do mistral's have overdrive?

or do you mean kickdown?

 

[SteveN]

Hi Plank, there is an overdrive switch on the gear selector, when it happens its the same as switching the overdrive off but without the warning light

cheers
Steve

 

[(RIP) PLANK]

Hi Plank, there is an overdrive switch on the gear selector, when it happens its the same as switching the overdrive off but without the warning light

cheers
Steve

cheers, i didnt know that!

 

[SteveN]

No one ever come across this problem then ??

cheers
Steve

 

[lacroupade]

Steve it could be a couple of things. The O/D is electrically switched so could be an issue with wiring or some part of the circuit.

If its the gearbox you just have to wait til something breaks as investigation is horrendously expensive.

Auto boxes for these are like hens teeth and a rebuild costs around £1500-2000 if its a mechanical fault.

I'd go for an electrical fault for now, especially as its intermittent.....

 

[SteveN]

Hi, thanks for the reply, hoping its not the box thats for sure !!!

wasn't sure wether it was going to be an electrical problem or just a case of changing oil perhaps.

cheers
Steve

 

[vatco]

Don't know anything about Mistrals but Auto's in general are funny things and prone to play all sorts of tricks for no apparent reason. They are affected by temp as well as condition of fluid etc.
When was the last time the trannie had its oil changed and filter cleaned?
You are correct in the fact it could be down to this but check other things as well

Point is there may not be anything wrong. Something may have just changed.
Does the O/D oporate normally otherwise?
Do you know what the settings should be? (should be in the W/shop man. or someone else should be able to tell you on here)
Have you changed anything recently?
What where the circumstances when you first noticed this happening?
Does it stay in if you raise the speed slightly?
Does it drop out on kick down?
Do you get a double kick down (i.e) if you are in O/D and you floor it at about 65 can you feel the O/D drop out and then the Tranie change down a gear?

I don't know on the O/D speed setting on the Mistral but on a Daimler I own the O/D will switch out below 58mph and back in again at about 63.

That was great----I got used to it. I just used to boot it up to 70 regardless and set the auto pilot to 60mph and let it look after itself

Some time ago I changed the rear tyres and found that those speeds had altered. It puzzled me for ages and then I discovered that the rolling radius of the tyres I had put on was slightly different. A bit of research later I discovered that the O/D was controlled by the ECU for both the engine and the Gearbox and because the RR had changed so had the actual speed of the car giving me the impression that something was amiss

 

[lacroupade]

Don't know anything about Mistrals but Auto's in general are funny things and prone to play all sorts of tricks for no apparent reason. They are affected by temp as well as condition of fluid etc.
When was the last time the trannie had its oil changed and filter cleaned?
You are correct in the fact it could be down to this but check other things as well

Point is there may not be anything wrong. Something may have just changed.
Does the O/D oporate normally otherwise?
Do you know what the settings should be? (should be in the W/shop man. or someone else should be able to tell you on here)
Have you changed anything recently?
What where the circumstances when you first noticed this happening?
Does it stay in if you raise the speed slightly?
Does it drop out on kick down?
Do you get a double kick down (i.e) if you are in O/D and you floor it at about 65 can you feel the O/D drop out and then the Tranie change down a gear?

I don't know on the O/D speed setting on the Mistral but on a Daimler I own the O/D will switch out below 58mph and back in again at about 63.

That was great----I got used to it. I just used to boot it up to 70 regardless and set the auto pilot to 60mph and let it look after itself

Some time ago I changed the rear tyres and found that those speeds had altered. It puzzled me for ages and then I discovered that the rolling radius of the tyres I had put on was slightly different. A bit of research later I discovered that the O/D was controlled by the ECU for both the engine and the Gearbox and because the RR had changed so had the actual speed of the car giving me the impression that something was amiss

Vatco the o/d on the terrano is absolutely binary only, i.e. you use the switch on the gearstick to turn it on or off, nothing else affects or operates it.

Kickdown is just that, i.e. it drops a cog in the main box, doesn't change o/d at all.

Thats why I favour an electrical fault at first.....

 

[SteveN]

Hi guys, nothing has been changed recently and everything else is working fine, the overdrive when switched on at the gear selector works fine at all speeds and also ok when using the kickdown, but every now and then, when cruising along, if I need to ease right off of the accelerator ie foot right off no matter what speed I am doing it will change down a cog, at sixty odd miles an hour it goes from approx 2k revs to 2.5k revs. If I switch the overdrive off manually at the same speed I get exactly the same response and the same reading on the rev counter.


The car did this on the Monday after Christmas going from Eastbourne to Worthing, about 40 miles, started doing it about halfway there but was ok all the way home and has been ok since.

It just seems to happen now and again and lasts until the car has been switched off for a while.

Going to change the oil and see what happens I think.

cheers
Steve

 

[supertaff]

With it being a 1995 Mistral, could it be the O/D switch, or a solenoid feeling its age ?? Try switching in and out of O/D on tickover a few times.
If I remember correctly, there is a light on the dash that tells you when O/D is switched OFF.
Matt.

 

[lacroupade]

With it being a 1995 Mistral, could it be the O/D switch, or a solenoid feeling its age ?? Try switching in and out of O/D on tickover a few times.
If I remember correctly, there is a light on the dash that tells you when O/D is switched OFF.
Matt.

You're spot on, there is, and the age makes me suspect an intermittent electrical fault before owt else, but could be a sensor, solenoid or anything really.....