just go by how it feels.... after a while you will be able to feel the power curve, and when it starts to flatten out, you should shift (of course shifting a little sooner won't do anything but save you on gas).
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If it moves and it shouldn't, use duct tape.
If it doesn't move and it should, use WD40.
i have a 4.0 with a tach... i shift around 2500RPM's and normally.. 20mph into second.. 30-35mph into 3rd... 45-50 into 4th.... and 60-70 into 5th.. hope that helps
Dont race a ranger, less youve built it to. All its going to do is rip up the engine and destroy a beautiful truck. And I think youll be disappointed in the results w/o some serious engine work.
Ya, I just mean, try not to make a habit out of it. Sure you can push it a few times to see just what kind of response and power the engine will push, just dont make a habit out of it, or itll die ALOT sooner.