Peaklander Posted January 28, 2022 Share Posted January 28, 2022 Hi, recently I looked at my BFG tyres and realised that the front nearside has worn more than the offside. I know that there is more than one reason for this, I could just be driving around in circles for instance. However I am changing my swivels and was checking the parts diagrams here at LR Workshop. There are seven bolts for the ball to axle. Six are identical, number 9 but one, number 10 is described as 'pin' with a shank that is a tight fit in the ball hole. I believe that this is to ensure that the ball is presented to the axle in a specific position. Guess what - on my worn side there isn't one, all seven are the same. So I think this might be the cause. I do have one on the other side. If this pin bolt precisely sets the rotation position of the ball, that is settling the castor angle I think. What does it affect, does it affect tyre wear? I know that I have pretty-much answered my own question but I'd be interested in your comments. If it's specified it must be needed and all that... Quote Link to comment Share on other sites More sharing options...
western Posted January 28, 2022 Share Posted January 28, 2022 Mike at Brit Rest in Canada mentions the single bigger bolt at the start of this video part 3 of a front hub/swivel rebuild. when I had my front axle in bits last year I just refitted the 7 bolts in any of the 7 holes, not had any undue tyre wear yet. Quote Link to comment Share on other sites More sharing options...
Peaklander Posted January 28, 2022 Author Share Posted January 28, 2022 (edited) @western It wont matter which hole it's in, it just fixes the swivel at a specific rotational position, without the variability that you would get without it. Did you notice if the special bolt was amongst the seven? Whether or not the mis-position is enough to affect tyre wear, I don't know. Edit: thanks for the link to Mike's video. I hadn't watched that. He's rather sceptical about the variability that missing-out the bolt would produce - but he fits one anyway! Edited January 28, 2022 by Peaklander Quote Link to comment Share on other sites More sharing options...
uninformed Posted January 28, 2022 Share Posted January 28, 2022 Let’s say the amount the ball could rotate without the dowel bolt is 0.5mm off centreline, let’s say the PCD is 100mm. Then that would be a 0.57 degree change.. That won’t cause a noticeable difference in tyre wear. My front housing has nearly 1 degree difference from L to R in the mounting flanges. Fortunately it’s greater on the L side. Regardless I would still fit the dowel bolt. It’s definitely there to pin the castor on point but may also be a little insurance for rotational forces (braking and acceleration are going through the swivel assembly) 1 1 Quote Link to comment Share on other sites More sharing options...
western Posted January 28, 2022 Share Posted January 28, 2022 I did'nt measure the bolt diameters & AFAIK the bolts are original but the swivel balls are teflon coated, these were fitted years ago. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted January 29, 2022 Share Posted January 29, 2022 There was a topic on this a while back, can’t remember the consensus in the end. Can’t remember what my opinion was then, but thinking fresh now I can’t see the bolt making that much of a difference unless it’s a proper shoulder bolt and there are two of them as the swivel ball to axle is not that much of a tight fit itself. 1 Quote Link to comment Share on other sites More sharing options...
uninformed Posted January 29, 2022 Share Posted January 29, 2022 Just about to fluff about on my build so dug some bits and bobs out… Factory original standard swivel ball bolt - M10 x 1.5mm - 9.77mm at shoulder Factory original dowel bolt for swivel ball - M10 x 1.5mm - 10.50mm Holes in swivel ball flange - 10.70mm Spigot on swivel ball - 63.50mm rebate in axle flange - 63.65mm PCD ~95mm I installed 4 standard bolts finger tight (no head friction) and tested movement. Then installed the dowel bolt same ( no head friction) and depending on which hole I picked reduced the movement from 25% to 85% (almost nothing ) So if you are anal, pick the best hole or get 2 dowel bolts per side (and pick best holes) Quote Link to comment Share on other sites More sharing options...
Peaklander Posted January 29, 2022 Author Share Posted January 29, 2022 Thanks for the detail @uninformed. I have a replacement for the missing bolt in an order coming from Paddocks. When I pick it up I guess i could grab another pair. it will be interesting to see if they are more snug in a specific swivel hole. Quote Link to comment Share on other sites More sharing options...
uninformed Posted January 29, 2022 Share Posted January 29, 2022 22 minutes ago, Peaklander said: Thanks for the detail @uninformed. I have a replacement for the missing bolt in an order coming from Paddocks. When I pick it up I guess i could grab another pair. it will be interesting to see if they are more snug in a specific swivel hole. As we know, with any mass produced product (not just LR) there are variables and tolerances. The bolts were fairly consistent, the holes in the swivel flange a little less so. I can forgive them, that forged steel is an absolute bugger to drill/machine, as attested to by anyone that has slotted them. Speaking of which and in relation to your thread, I’ve had mine done and we added one 10.5mm hole that will get a dowel bolt as the rest are now slotted and won’t do the same job. 1 Quote Link to comment Share on other sites More sharing options...
Peaklander Posted February 3, 2022 Author Share Posted February 3, 2022 I ordered three UYG500040 dowels from Paddocks, as I have one and as suggested by @landroversforever, two each side might be better. I clicked and collected but should have taken my vernier as they are the 'normal' ones. I rang and asked them to check their bins and it seems that there's no difference in their stocks of both. So I contacted Blanchards and they list UYG500040G so ordered three. However they are the same too. After talking to them on the 'phone, one has arrived in the post, so that makes it one each side, not two. Obviously there's not too much focus on using a dowel in the stub axle to axle! Maybe I am being a little bit too %^%l. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted February 3, 2022 Share Posted February 3, 2022 It would be interesting to compare the angular position of the welded flange each side of the axle - I wonder if LR decided that it wasn't worth carrying the extra line as the tolerance on the flange position was wider than the different bolts would locate it to. Quote Link to comment Share on other sites More sharing options...
uninformed Posted February 3, 2022 Share Posted February 3, 2022 Glad you got genuine, the aftermarket replacement bolts I have had a play with are junk. Aside from the head being bigger, which in turn means a bigger spanner and less clearance, there is NO WAY they are class 12.9 they are stamped. Just rubbish. Quote Link to comment Share on other sites More sharing options...
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