Forum Discussion
Bedlam
Jan 07, 2016Moderator
Kayteg1 wrote:Bedlam wrote:
My 275/70R18 spare was the same height as my 245/70R19.5 primary tires. I never had to use it, but it was like insurance you hope you don't need but still carry.
Your generic rpm difference calculates to 3.8% what is below 5% that seems magic border.
go to tire size comparison. )
To make 100% comparison you should go to tire manufacturer site and pull the actual rpm numbers to compare.
Both tire sizes were the same physical diameter between my 18" Michelin LTX A/T2 and 19.5" DynaTrac PD890.
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