Q: Car will not shift into fourth gear - 1991 Mercedes-Benz 300SE

asked by on September 07, 2016

My car has a mileage of 160,000 miles. It generally runs well. However, when it gets warmed up or when the outside temperatures are high, the car seems to develop shifting problems. The issue is specifically shifting into fourth gear. What could be the cause of this?

Hello. I would check the condition of the transmission fluid first as well as the level. If the fluid is old or low then this will occur. If the fluid smells burnt or has debris in it then the transmission would need to be rebuilt. Most of the time this is caused by the valve body failing which results in the valves to bind internally. You will need to take the vehicle to a transmission specialist to diagnose this.

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