Should you drive only to 50 mph with your brand new car?

No, you should not drive only at 50 mph with a brand new car. While it's a good idea to avoid excessive speeds during the break-in period (the first few hundred miles), limiting yourself to *only* 50 mph is unnecessary and potentially dangerous. Modern engines don't require such strict limitations.

Consult your owner's manual for the manufacturer's recommended break-in procedure. This will usually advise against sustained high speeds or heavy loads during the initial miles, but not necessarily a strict 50 mph limit. Varying your speed within reasonable limits is generally better for the engine than consistently driving at one speed.