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Rpm question

909 Views 7 Replies 5 Participants Last post by  firemansdiesel
I have read a few post saying they are around 1500 to 1650 rpms at 70mph. Mines is just over 1850. Is this correct . Hand calc on mpg is about 17.49. That's is over 5 tanks and 50/50 hwy/ city
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I'm going to guess your Tradesman came with 245/70/17 tires? Just like my '12 that is a ST (same as a '13 Tradesman) and all other trims that have 17' wheels come with 265/70/17 wrapped around them. That would be roughly a 150rpm difference, and the difference you see with RPM's compared to some others. All '13 SWR are 3.42's.

When I installed my 35" tires from my 245's, I went from 1800rpm @ 70mph to 1650rpm. This is with an auto tranny and a manual will be slightly higher rpm's.
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