Q: My truck is doing a very loud thumping sound and wont go over 25

asked by on November 09, 2017

My truck was good yesterday and today i went to turn it on to hear a loud thumping sound from the engine and it wouldnt go over 25 mph. Could it be the catalytic converter? I was told it needed one but i doubt it would make like a loud deep thumping noise please help

My car has 200000 miles.
My car has an automatic transmission.

In most cases a loud low thumping noise is an indication an engine main crankshaft bearing has gone bad or you are losing oil pressure in the engine. I recommend not driving the vehicle and contact a mobile mechanic like one from YourMechanic come to you and diagnose the noise to see if it is an internal engine noise or maybe another problem.

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