Timeking wrote:
Why did GM put 20 inch rims on a tow truck?
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I also think that since GM upped the tire diameter, they also had to recalibrate the speedometer, ...
If you are buying new, see if the dealer will swap wheels and tires with a different truck that has the size you desire. They should also re-calibrate the speedo for you.
It is not just GM ! Ford and I am sure Dodge is doing the same thing. The 2016-17 Ford Edge can be purchased with an optional turbo V6 engine. I am sure there is enough power there to tow 5,000 lbs
(maybe with additional cooling), but they limit it to 3,500 because that engine can only be ordered with the Sport package which include 20" rims with ridiculously low profile tires.