GORV - Digital Magazine Issue #47 | Page 17

RV FEATURE
Mr Young , an engineer , offered the following as possible reasons for broken wheel studs or loose / lost wheel nuts …
• The pitch circle of the studs in the ( imperial ) hub aren ’ t exactly the same as that of the holes in some ( metric ) wheels , such that all studs bend when the nuts are tightened ;
• The angle of the taper on the nuts is not the same as the angle of taper in the wheels ;
• Low-grade steel studs have been used ;
• The hole in the wheel centre is not compatible with the spigot diameter of the hub ;
• The serrated studs have not been “ fully driven home ” when pressed into the hubs , such that they gradually “ give a little ”, thus causing the nuts to become loose ;
• ' Rattle-guns ' set at unknown high-torque levels have been used to tighten wheel nuts ( rather than just undo them , causing the studs to stretch and thus become weakened ;
• Nuts being tightened in a circular pattern in one action , rather than in a criss-cross pattern , using two or three ( increasing ) torques ; and
• Wheel centres being highly dished , thus acting as a large spring-washer that gradually looses its tension and causes the nuts to loosen .
Paying attention to your van ' s tyres is a crucial step towards ensuring a trouble-free trip .
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