I just recently did a 1500mi road trip in my truck and am now noticing a strange noise coming from the engine. I would describe it as a high pitched whistle/squeal/rattle that occurs when there is a load on the engine around 2000 rpms. It happens when you step on the gas and the trans downshifts to accelerate on local roads or on the highway when you ease into the gas on a hill or to pass another vehicle (without the trans downshifting but still around 2000 rpms) and stops as soon as you back off the gas. Should note that I wasn't towing anything on this trip.

It's definitely a different sound than the turbo whistle (much deeper) and don't think it is coming from the belt.

Should also mention that right before the trip I had the dealer perform the 30,000mi service (std oil change, fuel filter, air filter, trans service and coolant drain). I'm always concerned when something like this occurs right after I've had the truck at dealer....

Anyone experience anything like this?

Thanks.

 

There was an issue with the heater cores on some vehicles. Here is the info on that:

It could also be a boost leak. Here is the post from "greggara" on TDS:

 

good read zero one!
reps to you

 

Yes, thank you.

The heater core noise seems to make sense since I've just recently starting using the heat this season, but my truck is a Job #2 build (build date 8/07 i think).

Is it possible that that TSB could still apply??

 

Probably not the same, but Ive noticed lately that when I lay into the pedal I'll hear a noise like a car horn. At first I thought someone was honking at me for gunning it. But then my wife heard it and turned around and started to flip off the guy behind us and I told her to wait. He was in a Chevrolet and had come upon us and kept trying to cut in front of me, and when I put him in the rearview my wife thought he was blowing his horn. Its fooled me more than once. Any ideas?

 

To be honest, I'm not exactly sure. Since you've just done a 30k service, you're still well within any warranty section that this would fall under though. Bring it back in and have them test it out. How easy is it to reproduce the noise?

Also, coolant drain / refill is not part of the 30k service as far as I know. Only the others you've listed. (Just had mine done as well.) Them draining / refilling the cooling system could be why the heater core is now acting up and making the noise since it is a part of that water loop.

 

Doesn't seem terribly difficult to reproduce the noise. I guess I'll have to bring it back in. Just an FYI, the 30,000 mi service notes indicates a cooling system drain and fill and they charged me for 1 (gallon??) of VC-7-B Anti-FR for $18. So I'm assuming they did something with the cooling system. Which also leads me to believe that it could be the issue with the inlet hose to the heater core. However, I would assume that that noise could be reproduced while in park?? which I am not able to do.

 

Not sure what your dealer has scheduled. Sometimes they seem to differ from that Ford says. For example, at 30k, they were unaware that I needed a trans flush and had no clue about the early build trucks having the canister under the bellhousing.

I just go by the PSD supplement and user manual in the glove box which, for the coolant, states "6 years or 100,000mi - change Motorcraft Premium Gold Engine Coolant (whichever comes first). After initial change - change MPGEC every 3 years or 50,000 miles."

VC-7-B is Motorcraft Premium Gold Engine Coolant, and is mixed 50/50 with distilled water... so 1gal makes 2gal of coolant. Not sure what they did with 2 gallons. Maybe topped it off? Though thats a lot to top off. Maybe they wanted to adjust your concentration for anti-freeze or anti-corrosion properties. There are test strips that supposedly indicate the chemical composition.

Your noise doesn't happen in park? Sounds like it needs a load on the engine (more airflow and/or higher boost). Have you checked the air filter box to make sure the filter is seated properly and the lid on tight? If you explain how to make the noise, I'm sure the tech will try that... or better, take them out for a ride so they can hear it first hand while not having to focus on driving.

 

Thanks for all the info. Perhaps they drained and flushed the coolant then put the old + some new back in. I'm always skeptical....

You're correct, the engine needs more load/boost to reproduce the sound. I'm going to check the airbox as you mentioned and see if that may be the issue, since they did open the airbox to replace the filter during the service.

Hopefully it's something that is diagnosable...I've had bad experiences with other vehicles trying to explain noises,etc to dealers and having them actually fix the issue.

Again, thanks for all the input. I'll follow up on the thread when I have more info.

 

No problem, and good luck with it! Looking forward to hearing what you/they find.

I hear you on handing the keys over and describing a noise. It's hard to put into words what you learn from driving the same vehicle for a while. It'd be nice if we could go in and just use their tools and computer resources.

 

FYI......So the dealer says it's a cracked "Y" pipe coming from/to?? the turbo and it will take two days to fix....

 

interesting that would of cracked, not so serious though.

 

I agree, nothing serious but I've heard they have to drop the frame crossmember and tranny or transfer case to get to it. Thankfully it's covered under warranty! On that note, does anyone know if this would be inluded in the 100,000mi powertrain warranty??

 

Ah, so it did end up being a cracked exhaust pipe, expansion joint, etc (all in the same area). Surprised you never smelled any fumes in the cab with the vent/heat/ac on.

I'm not 100% sure, but it should be covered under the 100,000mi powertrain. It is a part of the engine.

 

Does this noise happen like this?--

Hard acceleration from a stop with a trailer/load, when in the 55-65MPH zone in 4th gear, 30 psi boost, high 2000's rpm, and shifting to OD as you approach 70?

This is what my truck started doing today. Strange "moan" and I could feel the vibration on the floor with my feet that goes along with the "moan".

It only happens for me in 4th gear and pushing hard to get to 70 with a decent load on the trailer. I thought it may be time for a transmission service?