Q: I changed my oil pan gasket and now there is a knocking at the back of the oil pan, what could it be

Hello, thank you for writing in. The first thing to do is make sure your oil level and type are correct. If you suspect that there may be a mechanical issue with the components towards the bottom of the engine, you will want to remove the oil pan and do a visual inspection. Check the rods for excess play, but do this gently. Check the oil pan for signs of metal debris or shavings. This is an indication that the engine has major interior damage. Piston slap is another common occurrence, specially with older engines such as yours. Typically it goes away after the engine warms up. Further inspection will need to be done. For more diagnostic help, contact our service department to schedule an appointment.