2010 4.0L - Brief Squeak/chirp at startup

[Cameron58]

I took the belt off and started the engine. The chirp still occurred. So it's not a pulley.

I don't think it's the exhaust system either as I tried to shake it and there is no give or rattle.

I used the stethoscope on the starter, near the exhaust manifold, on the transmission and bell housing, nothing. I spent an hour last night having my wife start it and shutting it off while I was under it and all over trying to isolate the noise.

My only remaining idea is an engine mount squeaking from the initial torsion of the engine when it's first fired up. I have noticed the chirp when I accelerate from a standstill too. So this might be the issue. Should I just spray pb blaster on the rubber engine mounts?

 

[Turdle]

If you want to destroy them yeah.
You will end up in a real mess if you chase noises with lube. You need to identify the worn-dirty item and clean-replace it. Or, ignore it until it get bad enough to find easily.

Try water in a spray bottle instead.

 

[donalds]

View attachment 422555

Still my vote

 

[Cameron58]

If you want to destroy them yeah.
You will end up in a real mess if you chase noises with lube. You need to identify the worn-dirty item and clean-replace it. Or, ignore it until it get bad enough to find easily.

Try water in a spray bottle instead.

Would the petroleum in the pb blaster deteriorate the engine mount rubber? Seems odd that they wouldn't use a rubber that's compatible with oil considering it's likely exposure to oil.

Or is there some other reason? I have no idea what else it could be. I'm about to take it to a shop and let them figure it out. 2 hours after work is starting to add up. And throwing replacement parts at it is getting costly.

Alternatively, I'm considering selling this pos. Just replaced a door lock actuator and had the transmission rebuilt at 140k miles. And now I'm reading that it's not uncommon to have to have the timing chain tensioner cassettes replaced at 150k miles which involves pulling the motor and tearing into it pretty far. So I'm not looking forward to that bill. Never getting a Ford again (for more reasons than just this).

My wife's impala has 240k miles, 12 years old, and I haven't had to replace anything major except a few bulbs and an evap sensor.

 

[94Eddie]

All brands have winner and loser vehicles. Look into the Chevy V8s with displacement on demand. The same with Dodge V8s of certain years. GM and Chrysler have V6s and transmissions they have put in numerous vehicles that are nightmares to own. We had a 2003 Taurus with the DOHC V6 that ran for 200k miles with little more than maintenance being done to it. One needs to do research before buying any used vehicle. When it comes to 3rd and 4th gen Explorers I think the 4th gen V8s are the best of the lot. The engines are reliable with few inherent issues and the transmissions in them are very reliable. Over the years, I have seen very few catastrophic issues reported on the 4th gen forum here regarding the 3V V8s and the 6R60/80 transmissions. Lack of complaints or issues reported in forums is a good indicator of a vehicle's overall reliability, IMO.

Back before the internet it was hard to know which vehicle to buy to avoid problems. These days a few hours browsing through forums, and/or YouTube, will show all one needs to know about a vehicle they are considering to purchase. One gets the benefit of knowing the collective experiences of millions of people condensed into a small, easily digestible package. One resource I rely heavily on when buying a vehicle is Carfax. It isn't perfect but a Carfax report says a lot about a vehicle that is important. It tells where a vehicle has spent its life, can show a good maintenance history and if collision damage has been reported. They are not foolproof but are useful, IMO. Plus, knowing if a vehicle has spent its life in the Rustbelt is very valuable information. I won't buy any used vehicle that has spent more than 5 years in the Rustbelt or heavily salted areas.

I wouldn't blame you for dumping your Explorer but you just might end up with something worse if you don't thoroughly vet any vehicle you intend to purchase.

 

[Cameron58]

Still my vote

Would this squeak without a belt on it though? My understanding is the torsion from the belt twists or shifts that rubber dampener on the pulley. With no resisting force on it other than inertia, I doubt that would be it...

I'll see if I can get that stethoscope down there to listen, without chopping my hand on the engine fan...

 

[donalds]

Would this squeak without a belt on it though

Yes it will
Look up some threads on it
I took a paint marker and marked the front of the HB
Then look for the marks to move

 

[Cameron58]

Yes it will
Look up some threads on it
I took a paint marker and marked the front of the HB
Then look for the marks to move

Nice, that's a really good idea. Thank you

Was the shift pretty noticeable with those lines?

 

[donalds]

Was the shift pretty noticeable with those lines?

ANY shift = a bad unit

 

[Cameron58]

I'll check the harmonic balancer pulley, but also, if I were to replace the engine mounts, could I support the engine with a jack from beneath or does it have to be supported from above?

 

[donalds]

I'll check the harmonic balancer pulley, but also, if I were to replace the engine mounts, could I support the engine with a jack from beneath or does it have to be supported from above?

I'm not sure good question

 

[Cameron58]

I'm not sure good question

I used a paint marker and started the engine several times, hearing the squeak every time. The lines did not shift at all.

So it's either the engine mount or some other mystery. Either way, I'm going to take it to the shop and have them diagnose it. I've spent hours and hours dicking with this.

 

[Cameron58]

Just an update to close out this thread: turns out it was a loose exhaust heat-shield above the torque converter. This started happening right after some transmission work, but as soon as I got it home, I pulled the alternator to run spark plug wires and replaced the spark plugs.