Confirm the replacement bulb is fully seated and the headlight assembly is correctly installed in the core support, since a bulb swap rarely changes aim. If the beam is still high, use the vertical adjustment post on top of the outer headlight frame under the hood, then recheck aim with the hood closed because hood pressure can shift the frame.
The owner of a 2002 Chevrolet Blazer replaced a headlight bulb and found the new beam about 3 inches higher than the other side. The expert said the bulb was likely not seated correctly or the headlight was not installed properly in the core support, noting that bulbs rarely change adjustment. The owner later said the correct bulb was out of alignment and described a vertical adjustment post under the hood, warning that closing the hood can press on the frame and throw the lights out of alignment again.
