james.c Posted September 23, 2018 Share Posted September 23, 2018 Hi all, I'm spanner checking my 620S before a track day at Silverstone on Tuesday. I had a total failure of the diff carrier this year because I had not been checking the diff and carrier bolts every track day (the carrier sheared off and I had to be rescued from the west coast of Wales!). I'm new to this so just wanted some help to identify the correct bolts so I get the torque right. I couldn't get everything in one photo (sorry!) so I've labeled the 4 bolts in the two images below. My best guess are: 1 = Rear carrier bolt (so from build guide "x2 M10 plain on rear - 47Nm")2 = Upper differential mounting (??) so 54Nm3 = Forward carrier bolt (so from build guide "x2 M12 caphead on either side - 81Nm)4 = Lower differential mounting (??) so 54NmI'm obviously just worried that I could be completely wrong here and do some damage if I under / over tighten the wrong thing!Thanks for any help you can give. J Link to comment Share on other sites More sharing options...
Jim 123 Posted September 23, 2018 Share Posted September 23, 2018 Looks correct to me. On my build the carrier frame mountings to the chassis were specified at 60Nm but this has probably been revised. You might want to consider paint marking the bolts heads etc for quick visual checks that things are not going anti clockwise with use Link to comment Share on other sites More sharing options...
james.c Posted September 23, 2018 Author Share Posted September 23, 2018 Thanks Jim,Much appreciated. I got confirmation from a couple of friends earlier too so went for it (and I've used a marker for a quick check next time!). I've done 2 track days since it all collapsed and nothing was loose this time. Long story but I have my suspicions that it was not torqued up properly in the factory. But the manual does specifically say to check them on the 620 so can't really complain! J Link to comment Share on other sites More sharing options...
ChrisC Posted September 23, 2018 Share Posted September 23, 2018 The upper diff bolt (the long one) in my S3 metric kit was a imperial 1/2” x 11” therefore it’s a 3/4 socket you need Link to comment Share on other sites More sharing options...
jamesclarkson Posted September 24, 2018 Share Posted September 24, 2018 I'm pretty sure that some of these are 'wire locked' on the race cars to help prevent a total failure. Might be worth looking into. Link to comment Share on other sites More sharing options...
7 wonders of the world Posted September 24, 2018 Share Posted September 24, 2018 Or use Schnorr locking washers Link to comment Share on other sites More sharing options...
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