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Quote: Originally posted by Petemate on 27/5/2013

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I don't know what we will find in the manual of the new (to us) caravan we will be collecting this Friday. However, I note that alloy wheel bolt/nuts on cars are normally much higher torque than steels. EG, usually 65 ft/lbs for steels, approx 80 ft/lbs for alloys. I assume that it will be the same for alloys on caravans?

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Not necessarily as the wheels on my caravan are steel but on the car they are alloy. Checking in both handbooks for Coachman and my Volvo the torque settings for the caravan steel wheels are 85-90 Nm. and the Volvo alloys 90 Nm. so even though the wheels are different material the torque settings are very much identical. Alloy wheels are cast in a die (mould) and steel wheels are formed differently by being pressed out of sheet steel but after the alloys are cast they drill 5 holes on a PCD (Pitch Circle Diameter) and then press 5 steel inserts into the alloy wheels afterwards which are the 5 centres that the wheel bolts go through, so in either case the torqueing of bolts is actually a metal to metal contact so there wouldn't be much difference in the torque setting figures. The bolt and wheel fixings are actually created by pressure on the tapered shoulder directly behind the hexagon so if there is the slightest bit of dirt etc. between the two contacts it could possibly cause the wheel bolt to loosen and once one is loosened then the vibration can lead to the remaining four coming undone. So it's always best to ensure that each of the bolt tapers are clean before tightening and not to over apply the recommended torque either as this causes the threads to stretch which can be just as bad as being under torqued.