IF you let the engine shift before redline the engine will slow down TOO much for the next gear & will take much longer to get the rev's up to the higher HP area. HAVING 5 gears(1997+ later) instead of 4 allows the engine to build revs quicker. Also the rear axle ratio can be changed due to the "overdrive" ratio in the 5-speed. Better mileage & acceleration!

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MERCEDES Benz Master Guild Technician (6 TIMES)
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