As the Explorer evolved apart from the Ranger, considerable weight was added, and the ride height (and therefore center of gravity) was raised. But Ford kept using the same tires as they had used for the Ranger, and it was found that this could lead to problems. The tires in question were made by Firestone, and when these were under-inflated, the extra weight on them would often cause them to overheat. Once overheated, the tread would separate from the rest of the tire, causing a blowout. This would be bad enough, but it was soon found that most drivers tended to panic in this situation and do the opposite of what they're supposed to.