Sorry if this has been beat to death. Just picked up a 1994 and my manual says to tow in overdrive. Suggests to kick it out for long downhills for extra engine braking. Really? Rule is to never tow in overdrive. The details are short box, 5.0L, 3.55 gears

 

I would NOT tow in overdrive unless it's something like a little light utility trailer. Lock it out.

 

Really. Read the owner's manual, and follow its instructions. This is not your grandfather's O/D.

...and read the REST of it, too. It explains how to calculate the truck's max safe towing capacity.

 

Usually a 302 with 3.55s struggles to do above highway speeds anyway, so with a trailer it'll lug down even more. If it is constantly hunting between third and fourth, lock it out. If it can hold the load in 4th, let it be.

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