ddruker

I'm bringing my Platinum Powerboost back to the dealer two weeks after I first picked it up to address several delivery quality issues.

The one I'm most concerned about is a loud buzzing / grinding noise, that is coming from the underside of the truck, generally located below the front passenger seat and outside the vehicle. It sounds like a high-speed fan or pump with a bad bearing. I hear the noise as soon as I turn the truck "on" - meaning the gasoline motor is not on and the vehicle is in park but the truck is in "run" mode. I would expect a hybrid to be silent when "turned on" in electric mode but not doing anything - but this whining / buzzing noise is always there. The head unit is off, the seat blowers are off, the climate control / AC is off, and this noise is NOT coming from the passenger warning noise speaker - it's always on, and it's coming from the area of the transmission, which I can feel is vibrating. Here is a video of what it sounds like.


Update Sept 2021. After four visits to the dealer to diagnose this and other issues, the mechanics think that that the noise is coming from the electric transmission fluid pump. It turns out our hybrid transmissions have two transmission fluid pumps, a mechanical one like a normal transmission, plus a second electric pump. The current theory is that the electric transmission fluid pump comes on immediately when the truck is put into run mode to begin lubricating and or cooling the transmission for electric driving and that the electric pump is what is making the loud buzzing noise.

For the rest of you that are seeing this problem, when you go to the dealer I suggest that when reporting the problem, you describe the issue as the electric transmission fluid pump is buzzing/grinding/failing, which you are concerned is going to destroy the transmission, instead of reporting the more generic "buzzing noise coming from under your truck."

What I have found is that when I simply report that there is a loud buzzing noise under the truck, the techs at my dealer misdiagnosed the problem every time because there is an existing Ford technical service bulletin - SSM 49589 - about transmission noise. This particular service bulletin is about gear train noise when the gasoline motor is running, which is obviously not the problem we are having with our trucks, but since it mentions noise coming from the area of the transmission, the techs at my dealership used it 3 times as an excuse to claim that the truck is operating normally. https://www.ranger5g.com/forum/threa...mission.11683/

Part of the reason for this misdiagnosis is that very few of the mechanics at my dealer have been trained on the Powerboost hybrid powertrain, and there are no other Powerboost vehicles on the lot to compare mine to. It took 3 visits to the dealer for them to actually put a mechanic who has been trained on the hybrid powertrain on my truck. I of course only learned this from the third mechanic, who was as confused as I was why the dealership would have untrained mechanics trying to diagnose a very specific hybrid problem.

In my most recent visit to the dealer, and only after escalating two levels up to the service director, for the very first time they brought out a mechanic that actually understands the hybrid powertrain and had been trained on it. He immediately understood the problem and unlike the previous two mechanics, was aware of the existence of the existence of the electric pump. He was very clear that there are so few Powerboosts in the market they have never worked on one yet, much less opened up a transmission. We agreed that the correct procedure to diagnose this problem would be to open up the transmission and bench test the electric pump to verify that is what is making the noise, and ideally to order a second pump to see if it is silent or if it makes the same noise. The mechanic said it wasn't clear he would be allowed to do all this, even though he thinks it is the right thing to do, as it's not his job to diagnose design problems.

A week later, after a second meeting with this mechanic, and after some back and forth discussion with other Ford techs, they are going to call the pump buzzing/grinding problem "working as designed" at least for now. They all agree that the problem is with the electric transmission fluid pump. He said in circumstances like this, Ford looks to see if they get lots of reports from different dealers of customers experiencing the same problem, and if they do then they will typically provide a fix. He also said they discussed why the noise occurs all the time. He said this is because they want the transmission to be fully lubricated and up to pressure so it can start rolling immediately once you put your truck into drive when in electric mode. He also said that the techs do "get it" that electric vehicles are supposed to be silent, and that this problem is most likely due to Ford's inexperience in building electric vehicles - the noise this pump is making would be masked by the gasoline motor running - the root cause here is that Ford engineers need to learn that electric vehicles sitting in park should be silent, and specify parts as such.

The net is that everyone that hears this noise on their truck and is bothered by it should report it to their dealer as a loud buzzing and grinding noise coming from the electric transmission fluid pump, noting that the noise is getting worse over time, and with a concern that the pump is failing and your transmission is going to get destroyed. If you use your F150 to tow, can also explain to the service advisor that Ford markets the truck for camping and pulling trailers, and this loud noise makes it impossible to use your ProPower generator in a crowded campground as it pisses off tent campers. Do not report this as a general noise coming from the transmission, and do not accept a diagnosis of the SSM 49589 which is specifically about gear train noise and not about the noise from this electric pump. There are already open threads on this problem in Ford's internal tech bulletin board system and if you experience this problem, make sure you get your tech to add to these threads. If you can get your dealer to replace your pump with a new one, please post here if the new pump is silent or at least quieter.

End of update

My question is whether any of you have also experienced this noise or a similar noise on your truck, and if so did you have a dealer look at it? What did they say? If it was fixable, what did they do?

For the record, the other delivery quality issues / bugs I have asked my dealer to document and/or fix are:
1) Moonroof shade grinding when trying to fully retract
2) Rear seatback leather wrinkled / detached in several spots.
3) Driver side rear door edge paint chipped/scratched at delivery
4) Loud buzzing / grinding noise coming from the electric transmission fluid pump when the vehicle is turned on.
5) Android auto periodically disconnects and won't reconnect in wireless mode
6) If you add more than two pages of preset radio stations, Sync 4 deletes them all when the truck restarts.
7) Lane-keeping assist introduces dangerous trailer sway when towing

Thanks,

Dan

Nelly101

I just test drove a 21 Limited Power Boost yesterday, and noticed the same noise while driving under 50 in electric mode. At first I thought I was hearing a distant lawn mower...lol But realized it's the truck. It would stop when you accelerated and the gas engine kicked in. I asked the dealer to check it out when i brought it back. I asked to confirm it was a normal occurrence. Did you get any reply back from your dealer to what it was?

Neil

vulnox

Not sure about OP, but people really need to be aware of the impulse sound the truck makes under 30 MPH. It's intentional and meant to warn pedestrians that a vehicle is coming, especially blind or distracted ones, since electric vehicles don't make typical engine noises. It increases in volume until about 25, then drops off towards 30.

ddruker

Thanks Vulnox. Yes I know where the speaker for the pedestrian alert is.

Underneath the truck, I can feel the transmission pan vibrating. The noise seems to be coming from the top of the transmission or above the transmission. Definitely sounds like a loud high speed fan or pump buzzing and rattling, perhaps with a bad bearing. Reminder this is with the truck powered on, in park, with the gas motor off and the head unit and climate control off.

UnkLeRaRa

I remember when the first round of electric cars were out in the early 90's, and everyone was so concerned about the cars not making engine noises.

If you've ever walked down the sidewalk with cars driving passed, you don't ever hear the sound of the engine unless it's a diesel or has an exhaust.

The sound of the tires is WAY louder than any corolla or civic (with no ricer can) "engine noise", lol.

vulnox

Yeah I get ya, that's why I noted I wasn't sure about your case, as your video didn't sound like that. I was referring more to the poster above mine, as I see people lump sounds together when most of the PB sound "complaints" I see are the alert sound.

NEbound

Silly question: are your buttcheek blowers on high?

Wife couldn't figure where that "noise" was coming from. It sounds like hell, even outside, but no swas.

7cbreeze

That would be a hoot

ddruker

nope. Like I said, everything is off. Head unit, a/c, butt cooler, gas motor, etc. The vibration is coming from the transmission or above the transmission - it's a high powered, high speed fan or pump. The butt coolers are audible when on, but much quieter and less buzzy...

dial912

Mine does have a quite pronounced fan type noise when powered on. I figured it was a cooling fan or pump for the battery system.

I personally like the back up sound, but the rolling forward pedestrian humming sound, to me sounds exactly like a wheel bearing going out in in the front of my old dodge journey.