I just purchased new E rated tires for my 2004 Dodge Ram 2500 2WD with 17 in rims. The tire placard says that I should have 50 psi front and 70 psi rear. These are the towing and loaded pressures, but there are no pressures given for when the truck is unloaded/not towing.

I searched the internet and on some of the Ram forums several said they ran 65 psi front and 55 psi rear or 60/50 when unloaded/not towing. Some ran 40-45 rear and 5-15 psi higher for the front. All these examples were on newer Rams with larger tires and rims. Since the 50 psi is my max pressure for the front, I don't feel comfortable running higher than 50 there. Just looking for some advise. I would like to improve the ride unloaded without damaging the tires. Any advise would be greatly appreciated.
Thank you,
Wailin

Tire pressure (along with size) affects load carrying capacity.

Higher pressure, higher load carrying capacity.

From your other post your truck is a Cummins, so you need all the load carrying capacity you can get on the front.

As far as the rear, you can drop the tire pressure some when not carrying a load but don't lower it too much.

Most 10 ply tires, load range E call for 80 psi max to get the highest load carrying capacity.
You're probably safe if you run them at 60 psi when there's no load. At full psi sometimes it will wear out the center of the tread when there's no real load (tire manufacturers vary).

If you put on a larger size as you were thinking about in you other post the larger size tire also increases load carrying capacity.

Find a public scale and get your axle weights unloaded. Then check the tire mfr site as many will list the pressure required for a given weight.

Unless you feel the truck rides rough I'd run the 50 psi front and 70 psi rear. I wouldn't go lower than 45 frt and 60 rear IMO. Diesel?

Yes, it's a diesel. I will leave the front pressures at 50 and experiment with the rear pressures. At 70 psi in the rear the trucks rides extremely rough. Hard to have a conversation with somebody when the road isn't good. Thanks again!

your owners "wallet" came with probably at least two booklets, say Michelin and Goodyear.
They would have load ratings for their tires at different air pressures.
Yeah, when unloaded you don't need them pumped all the way up!
Your tires will wear in the center, the ride will be stiffer, and the handling may suffer.
If you don't have the books, check the tire mfg. site.
Dodge left this info out of the owners manual on purpose, after all they are not a tire mfg!