Passion Espace Club

Bonjour à tous.
C'est la première fois que je pose une question à la communauté.
Quelqu'un a-t-il déjà changé, ou essayé de changer, le bloc hydraulique d'une boîte de vitesses Renault SU4, Aisin Warner TF80-sc ?
La boîte de vitesses semble lente à monter les rapports et rapide à les rétrograder. À l'approche d'un rond-point, la voiture rétrograde intempestivement, provoquant un à-coup désagréable.
En mode manuel, la conduite est plus agréable qu'en mode automatique.
Attention, si j'accélère franchement, la voiture prend rapidement de la vitesse.
Depuis septembre 2021, j'ai vidangé l'huile de boîte six fois. La boîte fonctionne beaucoup mieux qu'avant, mais pourrait être encore meilleure. Elle a parcouru 21 000 km (13 000 miles).
Je sais que le seul moyen de changer le filtre de la boîte de vitesses est de la démonter et de l'ouvrir. Je ne le ferai pas car c'est très difficile. J'ai une boîte de vitesses d'occasion provenant d'une Volvo XC90, qui possède la même boîte. J'ai démonté le bloc hydraulique et l'intérieur de la boîte, ainsi que le bloc hydraulique, sont comme neufs.
À mon avis, le seul moyen d'accéder plus facilement au couvercle de la boîte de vitesses est de démonter une grande partie de l'avant de la voiture.
Des idées ou des suggestions ?

Douglas.
Traduction par Google Translate.


Hello everybody.
This is my first attempt at asking the membership a question.
Has anybody changed, or tried to change, the valve body in a Renault SU4, Aisin Warner TF80-sc, gearbox?
The symptoms of the gearbox are it seems slow to change up and quick to change down. Approaching a roundabout the car will change down when it does not need to do so, producing an undesirable lurch in the motion of the car.
Driving in manual mode the car is more pleasant than normal automatic mode.
Don’t get me wrong, if I accelerate hard, the car will pick up speed quickly.
Since September 2021 I have changed the transmission fluid 6 times. The gearbox is much better than it was, but could be better still. In that time, it has covered 13,000 miles or about 21,000 Km
I am aware the only way to change the gearbox filter is to remove and split open the gearbox. This will not happen as it is very difficult to do.
I have a scrap gearbox from a Volvo XC90 which has the same gearbox. I have removed the valve body and the inside of this gearbox and the valve body look like new.
As I see it, dismantling a lot of the front of the car is the only way to get easier access to the gearbox cover.
Thoughts and suggestions?

Douglas.

Hi Doug,

Given that you have a spare gearbox at hand, which is currently taken apart, chances are you're probably the person in the best place to answer your question People tend to be reticent to work on automatic gearboxes.

Bear in mind the front end of these cars comes apart fairly easily: if it's your very first time into one of these, expect about an hour for the bumper and another hour and a half to remove the various rads (you will need to have the AC system professionally drained beforehand... or struggle around the condenser). Once you've seen where all the fasteners go it goes back together faster. Having another pair of hands around comes in handy when taking the bumper off and on.

Before attempting any of the work I would try finding out for sure the parts are compatible. It would be a bummer going through all the work just to find out you have to put things back the way they were.

Oh and a last thought: aren't these gearboxes electronically controlled? My colleague's advice (and he has literally thirty years more experience than me in the business) has always been: change the solenoids first, and with Renault original spare parts. I think on this box they're under a black tin on the front side - not a pleasant job but doable in situ. Might be worth checking too.