Hi,

I just replaced the fuel pump on my ‘10 4.0l with a new one made by precision fuel pumps. Everything works great, starts right up, no bogging, etc, but the pump is making a high pitched whining sound. It’s not over bearing like I can hear it in the cab, but it’s not the normal hum. Had a mechanic tell me that after market pumps will do that, but I don’t know. Any advice? Is it normal?

 

I've dealt with about 7 different aftermarket fuel pumps, and every one of them made a different sound than the other. Can't tell you why, but the mechanic isn't wrong.