How do I stay honest when the shop pushes me to upsell?

You are honest with customers, and you still feel the tug between the shop's numbers and the plain truth. That tension is not a sign you are failing. It is the sign of a working conscience in a job that constantly tests it. The people to worry about are the ones who feel nothing. Here is the thing the pressure hides: your honesty is the shop's real asset, even if the monthly numbers do not show it. A customer who learns they can trust you comes back for years and sends their family. A customer who feels squeezed leaves and tells everyone. Truth is slower money, but it is more durable money. Give yourself a simple rule you will not cross: recommend only what you would put on your own car or your mother's. When the pressure comes, measure the sale against that line. Hold it once, then again. Your name in that town is worth more than any single upsell.