I was reading other posts and came across someone asking about lugging the engine. Nowhere in the thread did anyone explain what lugging is. I was just wondering... What is lugging an engine and why is it bad?

 

Lugging the engine can only happen in a manual transmission car. It is when the engine rpm's are too low verses the speed of the car. For instance, you are driving at 20 miles an hour in second gear. The engine is probably turning at 2,500 rpms which gives you good power to speed ratio. Now, let's say you are moving at the same 20 miles per hour, but you have the car in 4th gear. The engine is now turning at around 1100 rpms which is just above idle. At this rpm, the engine has very little power, yet it's trying to move a 3,400 pound car. You are now lugging the engine.

 

when the engine s not at optimal rpms, the car will struggle to gain speed by vibrations