S40 '03 gearbox issue

[AidanS40]

Hello I bought a 2003 s40 1.6 petrol as my first car a few months ago. Don't know the exact name of the gearbox but it's 5 speed with reverse top left when the collar is pulled up. 86k miles.

When I was driving home I noticed going down from 3rd to 2nd is a bit crunchy, like worn synchro crunchy so I start double clutching going down and it rectified the issue, went into 2nd very smoothly, about 3-4 weeks later I go down into 2nd without double clutching and it was even smoother than when I was double clutching. Somehow the gearbox had managed to heal itself and it worked fine until last Saturday when I hit a large puddle at high speed in a patch of dense fog. Some water came through into the passenger compartment through the hole in the chassis where the gearstick comes out, after this the issue going down into 2nd comes back but double clutching no longer fixes the issue and 4th to 3 rd becomes a bit rough too, I can go from 4th to 3rd smoothly if I don't release the accelerator while shifting down, rpm stays at 3-4K and it goes in 98% smooth. Sometimes it will go down into 3rd and 2nd fine but it is rare

The issue seems too inconsistent to be down to worn synchromesh and the puddle thing making the issue return seems very odd

My father thinks it's something to do with the linkages being dirty/worn which explains why the puddle may have caused the issue to return.

Anyone have any ideas just what is going on with my gearbox?

Thanks, Aidan

[ITSv40]

Originally Posted by AidanS40

Hello I bought a 2003 s40 1.6 petrol as my first car a few months ago. Don't know the exact name of the gearbox but it's 5 speed with reverse top left when the collar is pulled up. 86k miles.

When I was driving home I noticed going down from 3rd to 2nd is a bit crunchy, like worn synchro crunchy so I start double clutching going down and it rectified the issue, went into 2nd very smoothly, about 3-4 weeks later I go down into 2nd without double clutching and it was even smoother than when I was double clutching. Somehow the gearbox had managed to heal itself and it worked fine until last Saturday when I hit a large puddle at high speed in a patch of dense fog. Some water came through into the passenger compartment through the hole in the chassis where the gearstick comes out, after this the issue going down into 2nd comes back but double clutching no longer fixes the issue and 4th to 3 rd becomes a bit rough too, I can go from 4th to 3rd smoothly if I don't release the accelerator while shifting down, rpm stays at 3-4K and it goes in 98% smooth. Sometimes it will go down into 3rd and 2nd fine but it is rare

The issue seems too inconsistent to be down to worn synchromesh and the puddle thing making the issue return seems very odd

My father thinks it's something to do with the linkages being dirty/worn which explains why the puddle may have caused the issue to return.

Anyone have any ideas just what is going on with my gearbox?

Thanks, Aidan

First off, if you post in the relevant S40/V40 forum you will get more replies. Not everyone looks in the general forum.

Having said that: you have the Renault box which is superb, but does suffer from linkage bush wear. Most probably the bushes in the front linkage that is worn. new bushes from Volvo cost about a tenner or so and it is a twenty min job to replace once the car is up in the air. Common problem and every Renault box suffers from this. Gear change will be transformed once done.