How imperative is it to change the spark plugs and wire at 100K miles. Truck is running fine and has 127K miles on it. Will be driving about 1800 miles pulling a 3500lb max load trailer
When going up a hill or when you seem to need more power, there seems to be a vibration coming from the motor, if I let off of the throttle, it seems to subside. Then back again if I’m going up a hill again when it looses power.