Sorry to title this as a guide, its just I couldn't find anything similar when I was searching on here, so thought I'd document my findings for the benefit of others in the future. Renault charge £2400 to replace the box - at least I was quoted that - along with others on this forum. We replaced the bearing(s) for £70. Although it did take 8 man hours.
My gearbox made an awful grinding noise in 1st & 2nd. When the gear was engaged and the clutch released, the gear lever would move in 1st and 2nd. I came to the conclusion (after searching on here too) that I needed at least a new shaft bearing in the gearbox.
*Note: I have heard of people having issues in 5/6th too.
The noise was terrible and prompted me to get out of either gear very quickly to avoid un-necessary damage to the teeth on the box. From my primitive understanding (before the g.box removal) the PK6 gearbox on my Laguna is a bit weak when it comes to the bearings.
I found a super friendly company called "fast track bearings". I can provide their contact details if required. They gave me a list of the bearings required although they did state they couldn't be specific as this box is shared with the 'traffic' - renault van, and that there have been slight modifications to it. So they sent me a set for both boxes and told me to let them know how I got on.
I only needed 2 x 30305 SPTXI made by NTM of Japan - identical to the ones there were already in the gearbox.
But in total, Fast track sent me:
1 x 30205 SPTXI
2 x 30205 SPTXI
3 x 30305 SPTXI
3 x 32206 SPTXI
I only needed 2 out of the sent and returned the rest.
*Note: I did not get the Diff bearings which are pictured here. If you have issues in multiple gears, then you might want to whip these out:
thats one side, and the other side is this one:
Like I said, I didn't get these two - luckily they weren't required.
Not the easiest job in the world, but never mind. The entire box must come out (unlike some vauxhalls where you don't have to). Regardless, the removal process did take 4 hours, but that is without a proper lift or working pit. So all in all, I didn't think it was that bad.
Thats the view, after gearbox removal from the top of the engine...
Thats the view from the nearside wheelarch.
The gearbox itself:
With the troublesome item successfully removed, it was time to crack her open (not literally). I was suprised to find that the box wasn't sealed with anything special and once the screws were removed, it came apart pretty freely....
You are looking at a PK6 Gearbox (code ont he outside said it was a PK6 S002.
Right, thats the view with the case off. The red square is an indicator as to where my bearing had failed. All the rest seem intact, so at first glance I thought we'd made a mistake!! But once the gears were pulled out, this is what we found........
The troublesome part was bearing number: 30305 SPTXI. We also replaced its parent bearing on the other shaft next to it. Just to be sure....
Above you can see the main shafts, the one to the right is for the diff. Then you see two that are parrallel, which we replaced the bearings on the bottom of the shafts. The top ones were fine.
Replacing the bearing(s):
We went over kill and used some gear pullers, but I'm sure people can improvise here...
Whilst my old boy was tasked with removing the inner track of the knackered bearing, I cleaned up the magnet which was covered in metal sharrings from the collapsed bearing - and also from a few teeth that had chipped on the outer edge...
Bearings were replaced and box was re-sealed. It then took another 4 hours to get it installed and all the pipes etc reconnected.
Happy motoring restored
I hope this is useful to some of you who are daunted by paying over £2k for something so trivial replacing. Although I wouldn't recommend it for the faint hearted. And it was a two man job.
But best of luck.