Grinding sound at higher rpms????

[Explorer7813]

Ok, i have a 2003 Ford Explorer XLT 4.0 V6 auto 4x4. It has 132,000 miles. Recently it has started making a grinding sound coming from under hood toward front of the vehicle. It only does it once RPMs reach about 3200. I have looked and listened and tried to figure it out, but no luck. Anybody have any ideas or has anyone had this problem and resolved it? Thanks in advance for any help.

 

[Rubberhead]

My '03 V8 does something that sounds like what you're talking about. I think there's two possibilities. 1: Timing chain tensioner needs to be replaced about $1,000 and/or 2) ethanol is causing 'spark knock'.

I still hear mine but it's a lot less noticable when I run non-ethanol gas. My Ford Service department said replacing the drive belt and timing belt tensioners would fix the problem.

 

[Explorer7813]

My '03 V8 does something that sounds like what you're talking about. I think there's two possibilities. 1: Timing chain tensioner needs to be replaced about $1,000 and/or 2) ethanol is causing 'spark knock'.

I still hear mine but it's a lot less noticable when I run non-ethanol gas. My Ford Service department said replacing the drive belt and timing belt tensioners would fix the problem.

I tried runnig ethanol free and ethanol in it but have not tried ethanol free in quiet awhile. Thats alot cheaper than the tensioner for timig chain. Is there any way to check for sure to see if it is the timing chain tensioner or anything to do with timing???

 

[2000StreetRod]

balance shaft chain?

There's a possibility that your balance shaft chain tensioner has failed and you're hearing the chain hit something inside the block. This link may help: Timing chain rattle resolution process - SOHC V6 Also make sure that the outer section of your harmonic balancer is not out of position: Harmonic balancer failure

 

[Explorer7813]

There's a possibility that your balance shaft chain tensioner has failed and you're hearing the chain hit something inside the block. This link may help: Timing chain rattle resolution process - SOHC V6 Also make sure that the outer section of your harmonic balancer is not out of position: Harmonic balancer failure

How do i go about checkin the harmonic balancer or the balance shaft chain tensioner?