Rear trailing arm bush bolts.

[deegee19]

HI All,I'm looking to replace the bushes on the rear trailing arms on my DG '85.

I've looked on the VW Heritage site and the bolts are £7 a piece which is considerable!.Does anyone know if they're just a standard size bolt or is there a reason for the high price?,many thanks,DeeGee

[CovKid]

They are high tensile obviously but providing you can match them from a bolt place, you'll be fine. Thats what I did.

[CJH]

I was looking at this myself the other day. VW Heritage helpfully quote the bolt spec: M12x1.50x110 1.5 pitch is the standard pitch, so I believe this is a perfectly standard size. Several of the ebay sellers that I looked at stated that for their part threaded bolts the length of the threaded part is (from memory) 2 x the bolt diameter plus 6mm. So that would make it 30mm for these M12 bolts. I haven't been out to measure up whether that's enough, but I suspect it is.

[dbz864]

Don't think there standard bolts,pretty sure there high tensile, jk sell them, as well as brickwerks, from memory brickwerks are cheaper till you add the £10 postage.

[CJH]

Don't think there standard bolts,pretty sure there high tensile, jk sell them, as well as brickwerks, from memory brickwerks are cheaper till you add the £10 postage.

I'm sure they must be high tensile, yes. Standard size though. ebay adverts that I've looked at have quoted '8.8' steel grade for high tensile bolts - is that sufficient?

[CovKid]

They are, said that to start with but other than that, theres nothing unique about them other than having a long shank. I managed to get some locally but may not be so easy depending on where you live.

[deegee19]

Great info cheers . I'll head down the bolt shop and see what gives. Thanks All.

[kit]

I gave up as all the fixing suppliers wanted to sell me boxes of 2 million so I went to Brickwerks got the right ones saved the hassle.

[CJH]

1.5 pitch is the standard pitch

I got that wrong - standard pitch for M12 is 1.75. So these 1.5 pitch bolts are technically 'fine' pitch. I doubt it makes much difference if you're buying the nuts to match, but what do I know - there may be a very good reason for using fine pitch here.

[Cob20]

1.5 pitch is the standard pitch

I got that wrong - standard pitch for M12 is 1.75. So these 1.5 pitch bolts are technically 'fine' pitch. I doubt it makes much difference if you're buying the nuts to match, but what do I know - there may be a very good reason for using fine pitch here.

Id say that because of the nature of the job, I would go with fine pitch screws, as they are less inclined to loosen through vibration as course threads would tend to do.

Its all down to helix angles, shear and tensile stress areas, but i wont bore you with that. If you did go down the course thread route you would be looking at anti vibration aids (no out of context posts please ) such as spring washers, locknuts or the like but not sure they would be advisable here.

theres always a load of blue loctite!!