GM-GMC: overdrive, size combinations, transmission shops

Question
Can I tow a travel trailer (5000lb in overdrive  with my 1990 C2500, 5.7 litre engine?  Thanks   Augie

Answer
Transmission shops will tell you to tow in third gear with the torque converter locked.

But, there are a lot of variations in rear axle/tire size combinations out there.  In addition, the 700R4 transmission is much improved after 1987.

So, I would say follow your own judgment:  Tow in overdrive if the vehicle is not struggling with the load.  Downshift manually on hills if required.

And change the transmission fluid frequently, especially when towing.