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**jocko** · 08-21-2018, 12:52 PM

Make sure you are referencing actual speed with a gps, your speedo is meaningless if your truck didn’t originally come with that rear gearing, which it didn’t. (Unless you’ve corrected the speedo gearing).

Also - are you absolutely certain you have 3.42s?

08-21-2018, 12:52 PM	#18
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,934	Re: I'm going crazy, need help with trans/gear ratio Make sure you are referencing actual speed with a gps, your speedo is meaningless if your truck didn’t originally come with that rear gearing, which it didn’t. (Unless you’ve corrected the speedo gearing). Also - are you absolutely certain you have 3.42s? Last edited by jocko; 08-21-2018 at 01:02 PM.