Thread: Its infectious
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Old 30-09-09, 06:10
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Ganmain Tony Ganmain Tony is offline
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Quote:
Originally Posted by Tony Smith View Post
The Chev 10 stud pattern uses smaller dia studs on a smaller PCD than the regular "wide 5" pattern used on other trucks. And 40's Fords have a different stud PCD to the more common Dodge/Inter truck wheels of the 60's and 70's.

Bob McNeill has raised a pertinent point regarding the spacers for the hubs (or spacing of the rims).

The pre-war 20inch wheels used on Fords and Chevs generally ran smaller tyres such as 6.00-20 or 7.00-20, while later trucks went to sizes such as 7.50-20 and 8.25-20. There are specific rims to suit each of these tyre sizes, and in some cases hubs too. The obvious reason is that wider tyres will require a wider rim, and dual wheels will need greater offset so the wider tyres dont foul each other when "bagged" out under load. But a more specific reason is that the centreline of the front tyre must be in a particular position in relation to the Kingpin Axis for it to steer safely and acheive optimal tyre wear. Putting a large dia tyre on a rim with offset for a smaller tyre will have the contact point in the wrong place. With the contact point in the wrong spot, steering effort will be increased. There was not a lot of camber and caster adjustment built into the design (ie: Nil!) of the front end, so it is critical that the correct combination of bits is used to set it up safely.
Thanks Tony... again and to you Bob. Critical info to stop me finishing up over a Cliff or as paintwork on the bull bar of an oncoming Kenworth.
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