1999 Dodge Ram 1500 - oil question

My 1999 Dodge Ram 1500 has 120,000 hard miles on her, (used in construction). The mechanic I took her to said to stay with 10W-30 motor oil.
I always thought as engines wore you should go to a higher viscosity oil, such as 20W-50,
or maybe even synthetic oil.
What do you think?
Thank you.

Why are you asking?

Do you believe your engine oil pressure is low?

Are you using a lot of engine oil?