Definitive 250 gearbox mount solution?

Discussion in 'Mechanical - Engine, Gearbox, Exhaust etc' started by dale.groves, May 9, 2016.

  1. Read below for a full guide... solution found and shared.

    Hi fellas. Ordered and collected the latest gearbox mount available for my 250 cup from Renault today, I'm now having doubts that I need the section of the mount that bolts to the gearbox, aswell as the part that bolts to the car which is what I have ordered. This is the part I have been given, the number differs from others posted on here prior. The info available is a little vague and not all on one post, hopefully we can clear this up here, with all the info needed to do the swap, then sticky it. This is the part I have at present.


    Also, if anyone can share pics clearly showing which holes on the mount need to be re-drilled etc. That would also be good.


    Sent from my HTC One_M8 using Tapatalk
    Last edited: May 28, 2016
    911R likes this.
  2. I take it this is the mount that has the piss weak bolt underneath the battery ? If so, I'm surprised mine hasn't broken yet !
  3. Yes mate. I'm hoping someone who's done the swap can clarify a few things I've queried above....

    Sent from my HTC One_M8 using Tapatalk
  4. Oli


    Id appreciate this information too, as I'm still running the original bolt.
  5. -Jamie-

    -Jamie- RSM Moderator

    You need the other part, That part you have sits on the top.

    The other part has the hole that needs retapped to suit an M12 bolt.
  6. OK mate, so do I need to use both parts just to be sure...

    And do you have a pic of what it looks like after the drilling and tapping is done? Cause looking at the smallest bolt hole on the mount, I can't see an m12 bolt fitting lol. Also, what length and thread pitch bolt is to be used after?


    Sent from my HTC One_M8 using Tapatalk
  7. Anyone please?

    Sent from my HTC One_M8 using Tapatalk
  8. OK so here goes.

    First you need a new mount, latest revision available, easy way of doing this is give you're Renault dealer the reg of a 275 cup s.


    Once you have this, time to take stuff off. Remove battery tray and airbox to access mounts. Top mount is held on by 4 16mm bolts to chassis and one to the gearbox side mount. Gearbox section of mount is held on by 3 18Mm bolts.

    Support the gearbox with a Jack, remove the bolt through the centre of the top mount, and lower the gearbox for ease of access.

    Remove the top 2 16Mm bolts from the mount, and literally slacken the 2 lower bolts as they are only locators and don't need to be removed completely. Then take this mount off.

    Now remove the gearbox side of the mount by removing the 3 18mm bolts. This is the section that needs modification.


    You need to drill and tap this hole to suit a m12X1.5 bolt. Then get a bolt to suit, making sure the threaded section of the bolt is 50mm long. Mine is slightly longer as there is space below the hole. Also pay attention to getting a washer 30mm wide for correct support on the top of the mount. I used an E type bolt to allow for a more solid fit with the socket when tightening and applying more torque.

    Once you have the mount modified and the suitable bolt sourced, refit is reversal of removal... leaving


    All done.

    Sent from my HTC One_M8 using Tapatalk
    ~Shaun~, 911R, Genty and 3 others like this.
  9. This would probably make a good sticky to point people to.

    Sent from my HTC One_M8 using Tapatalk
  10. Oli


    Nice one Dale - thank you.

    Thread should probably now be moved to the guides section.
  11. So the 275 mount is better than a 250 mount, but still not good enough, and thus you need to upgrade the bolt, or how are we to interpret that?

  12. Nice one Dale, I am planning on doing this at the weekend so this is a great help.
    Last edited: May 31, 2016
    dale.groves likes this.
  13. If I'm honest, they look identical. But they are different part numbers, and the fellow at Renault said it was a revised part. So change it for good measure, but beefing the bolt up is the main reason for this write up.

    Sent from my HTC One_M8 using Tapatalk
  14. I haven't had this part fail yet. What am I doing wrong ? hahaha
    Zs_phil likes this.
  15. Don't jinx it but me either haha
    (touch wood)
    TEV250 likes this.
  16. I will point out, I hadn't experienced the failure either, but enough have to make me take notice, the mainstay of the use of the car for me is on track, where this apparent weak point will be under even more load. And the subsequent, gearbox dropping onto the subframe or Driveshafts, could be the cause of a proper accident on track, not to mention the inevitable gearbox and driveline failures.

    You don't have to do this upgrade, but it's well worth considering, and the info is here for whenever you want or need it [emoji106]


    Sent from my HTC One_M8 using Tapatalk
    Benno996, TEV250 and Zs_phil like this.

  17. I do agree dale and it is a very informative thread and will be very useful for present and future owners
    And it is what the site needs ;new informative info about our cars no doubt owners Google what's wrong and how to fix their pride and joy and no doubt I will at some point after all that's why we are all here to learn about our cars while chatting in between
    Good work
  18. Makes sense.. Any chance I could persuade you to post the part number? The 275 is not available in Denmark, so can't look it up using a registration number.. Thanks..
  19. 11 22 120 65R

    Sent from my HTC One_M8 using Tapatalk
  20. Why replace the existing mount, simply remove, retap the bolt hole to a larger diameter bolt and replace
  21. I don't think there's anything wrong with simply replacing the suspect bolt.... but I also don't think replacing the mount at the cost of £70 is a bad idea.

    Sent from my HTC One_M8 using Tapatalk
  22. dd18ee3bbff7e4aa48316d902e95849f.jpg

    I picked up this beasty, m12x1.5, 50mm 12.9 grade, should do the job. Now wheres my tap and die kit gone...
    TEV250 likes this.
  23. Resurrecting this thread.. Which parts do I need to do this job ?


    Sent from my iPhone using Tapatalk
  24. Buy a new (15)
    Replace (17) with a thicker bolt
    Drill and tap (13) to suit the thicker bolt.

    There is a full guide on this thread mate.

    Sent from my HTC One_M8 using Tapatalk
    Mikec911 and TEV250 like this.
  25. Did you replace the full mount or just the bolt durmz?
  26. -Jamie-

    -Jamie- RSM Moderator


    I done mine the other week as well, it's easier to get to the two locating bolts on the side if you remove the arch liner and go in that way
  27. How much are the parts, Jamie? Is it a DIY job?
  28. Read the thread mate.........

    Sent from my HTC One_M8 using Tapatalk
  29. I did. £70. How did I miss that?
  30. -Jamie-

    -Jamie- RSM Moderator

    Yeah as Dale said, Only 70 odd for the mount itself. Pretty straight forward, the most time consuming/difficult part is stripping everything out the way then having to refit it all after you have changed the mount LOL
  31. Where did you chaps get the bolts from?
  32. I'm hoping this is the cause of my issues will be looking later.

    Would cause most of the symptons I guess. But my heart still thinks flywheel. Just not had a chance to look since Saturday but if this has failed I guess it'll be sheared bolt most likely.

    I've not got an air box as running a filter so assuming battery out and should have access
  33. -Jamie-

    -Jamie- RSM Moderator

    You should actually be able to peer down behind the battery and see the mount without having to remove stuff if you don't have the airbag, At least you can on my setup
  34. How come you decided to change the mount itself if you'd already added an uprated bolt? I've just replaced the bolt on my mount, wondering now if I should have done the mount too.
    ryan197 likes this.
  35. -Jamie-

    -Jamie- RSM Moderator

    Because its a better design and should in turn have less movement. Not to mention the old one had a fair amount of play in it and was clonking coming on and off the throttle, It was changed 40k or so ago as well when the original shat itself.

    I'll also be DIY uprating it as well similar to my other mounts. Not stiff enough
    noshadow likes this.
  36. Possibly could of seen it but figured I'd do the mod anyway and it would need to come out, took about 15 mins to remove all the bits.

    Bolt had sheered off and gearbox had dropped and moved forward, surprised I had no selector issues with the gears.

    Only issue now is I drove about 40 miles back like that assuming it was flywheel on Saturday.

    I'm going to drill out the bolt tonight thats stuck in, tap and thread to house a new grade 12.9 bolt M12 x 55mm so slightly longer. Will then put it all back together tomorrow morning and give brief visual inspection to the driveshaft and take it for a run.

    No vibrations through steering wheel and happy days, vibration and guessing I'll have marked the driveshaft in which case I've just seen it's £338 from Renault for OEM or £136 for a aftermarket part and will replace and stick a spacer on at the same time.

    Anyone changed driveshaft and if so should I stick with OEM or will aftermarket part be sufficient if I need to replace.
  37. Ok plan was to sort this today but yesterday got home the mount bolt was drilled out then it was tapped.

    Jacked car up, removed under tray, let car back down jacked gearbox, refitted and hey presto took for a drive and it's spot on again now all sorted so really pleased.

    Couldn't find axle stands but then it was around 10.30pm last night and just wanted to crack on before the weekend so can get myself to local beer festival today now without tackling it half cut later or tomorrow.

    Lesson learnt! and advise to anyone else. Change the bolt before it goes as it will do as it's to weak the 1 bolt holding it. If had more time I'd probably have revised the mount and had the bolt going through the bottom with a nut at the top that way rather than the risk of the bolt snapping the stress would be on the mount itself which I don't believe would fail.
  38. how so on the diy front dude? something I could do with doing
  39. I'm changing the bolt on mine tomorrow. I have an M12 x 1.5.

    I'm gonna drill it out with a 10.5 mm bit before tapping it out. Does this sound right?
  40. ianplymouth

    ianplymouth RSM Club Member

    has anyone got there old gearbox mount they want shot of ????? and the top part also

  • Share This Page