Noah Harbinger

That detail furthers my suspicion that Ford shot themselves in the ass by omitting the transmission fluid circulation pump on the otherwise-identical Hybrid transmission. I wonder if hyper-milers with the longest periods of battery-only use have seen the most failures?

I'll note that I'm >10 years in (only about 100k miles though) and my battery still seems to be doing fine (HEV_BAT_VAR_V, max variation in voltage between batteries, reads 0.01V, the minimum non-zero possible). I don't know the statistics, but I haven't heard about any abnormally frequent problems with the high-voltage battery pack.

I have no idea if this is an interesting problem, but I had a brake light out. Replacing the bulb seemed to fix it - but only for a little while. The next time I notice it's out, my roommate looks over my shoulder and says "is that corrosion on the contact?" I peer closer at it and see: Two holes! Kind of nuts to me, but maybe when the bulb burned out, it shorted, and the increased current melted through the contact. Still, I would have thought it would have blown a fuse before it melted a contact.

I don't check in nearly often enough anymore (probably a good sign given my car's over 10 years old), but I will enjoy reading if you post more!

I'd bet the project lead couldn't get a manager to sign off on adding another digit.

Yeah, I was pretty surprised by the turning radius, and had a few rear-wheel curb strikes when I first got it.

Personally, if I'm 'waiting a little bit' I'll let the light stay on so that I don't forget!

Not only is there no battery light, the car doesn't seem to notice if the battery is missing - I jump-started my C-Max and drove it without a battery installed, and there wasn't a single peep of concern on the instrument panel! I also used the flash-lights-pump-pedal procedure, and later bought FORScan Lite for IOS and verified that it had worked. Lots of data there to have fun with!

I figured it was time to find out! Bummer....

I live in California and I've had this problem too - during the summer, if it's more than maybe 85 out and I don't put up the sun shades - even for just a quick 15 trip popping in a store - I have no audio system until I let it cool down. It's irritating, but not irritating enough to deal with trying to get it looked at.

Well, I'll at least say that it doesn't sound like when my transmission was going bad ?

Something I wonder about that separate oil pump, or lack thereof for the plain hybrid, is how long do you have to drive with the engine off (e.g a long downhill with lots of regen and EV usage) before the lack of an oil pump causes heat problems for the electric motor?

I had this happen to me, but I forgot about it when I got home and forgot to pull the fuse. It resulted in a very, very dead battery.

Reading other threads on 12v batteries - I didn't reset the battery age, I suppose that plus reduced pandemic driving contributed to early battery failure.

My turn to join the low-voltage battery acid cub Came out and found the car dead, which coincidentally follows an entertainment system freeze the last time I drove it (Friday evening, found it Sunday morning). The jumper posts in the engine bay read 4 volts! I didn't think that was possible. Bought a new battery and when I went to swap it it, I found a lot of battery fluid in the battery compartment. The gas release tube had blown off - the part that sticks into the batter was still there, but the tube had separated from it. The battery bolt-down was corroded enough that after a few turns its threads stripped stripped off. Apparently it screws into a though-hole in the compartment, as I later noticed an area of dripping under the car. I dumped as much baking soda on it as I have, and it's still fizzing. I don't trust myself to clean it out sufficiently so I'm thinking of taking it to a shop, who is presumably experienced in dealing with that sort of thing. So much fun....

At some point I was trying to separate vehicle costs per mile into fixed cost per year and marginal cost per mile. I used KBB estimates for CMaxes of different ages and mileage to try to figure out what model they were using (I don't know if they use a model or base their numbers purely on auction prices) to figure that out. I wish I still had that spreadsheet, but if I remember correctly, the depreciation per mile was only about 8 cents per mile; the rest was all fixed depreciation per year. The upside to having a car that is not highly valued, it can't depreciate much further!

My lifetime peaked at 43.6MPG. After I replaced the stock low-rolling-resistance tires with a regular tire, I saw a pretty big drop in my long-term fuel economy: Between 20k miles and the tire change at 55k, it averaged 44.2 MPG; and it has run an average of 41.1MPG since replacing the tires, which works out to a drop of 7.5% - which is a good bit more than I expected. But that doesn't appear to be solely related to the tires: Comparing the speed on the speedometer to the speed reported by a GPS unit, the car no longer over-reports my speed. Previously it reported about 4-5% over-speed, now it's dead-on. Perhaps the new tires have a slightly larger diameter? Accounting for that, I suppose the low-rolling-resistance tires provided about a 3% improvement fuel economy. And I just had the transmission replaced - it would not be crazy to think that could have a measurable impact on fuel economy, though it is too early to tell so far. With all that, it's down to 42.6mpg lifetime.

Hmm, that is a good consideration. I first changed my air filter at 50k miles, but I have definitely driven a lot more dusty roads during the last 25k than the first 50k.

I don't feel completely confident in my recollections, unfortunately - remembering details often causes one to reconstruct memories to fill in the missing details. I really should keep a diary of such things. That said: I am pretty sure the volume of the noise increased over time, because I think at first I would only notice it when the stereo volume was low (when I had my dad as a passenger) or if I was driving with the windows down (when I would hear it reflected off adjacent cars). At the time I was thought it would be treated by the dealer as an insignificant noise complaint. That was at about 55k miles. Maybe it could have been a bearing replacement if I had taken it in sooner? I kind of just got used to it. By 74k (when I took it in) it was loud enough to hear over my music, but I don't have any specific recollections of it getting louder, so I think it just got progressively worse over time. I initially had the impression that it was worse when the car was cold. By the end it didn't matter. (Unless by 'frequency' you mean 'pitch' - the pitch stayed the same). I would say it got harsher over time, but maybe that's just a result of getting louder. If you're curious, the write-up on the repair invoice says: "Reman trans 10.60 EEC test pass. Ran oasis TSb 20-2219 related. Road test vehicle and verified TSB 20-2219 applies. Removed trans for inspection as per TSB. Split trans case and inspect. Verified pitting final drive and transfer shaft bearings. Found transfer shaft gear wore into dampener housing. Replaced trans as per TSB 20-2219 and flushed trans cooler. Updated trans strategy and road test." So it sounds like what SnowStorm showed pictures of (though my dealer didn't share any pictures with me ?) Yeah, my replacement was a remanufactured transmission. I sure hope it's a reliable remanufactured part. I'd definitely have had a hard time justifying that kind of a repair bill if I was out of warranty - I think I would have kept driving it around it died once and for all, and started setting aside money for the next car.

No news is good news, I'm hoping!

The 12-volt battery doesn't do much when starting a hybrid - it doesn't have to crank a starter like in a conventional vehicle. When mine died (2018, 5 years old at the time) I happened to have a 12-volt sealed lead acid battery lying around from a computer UPS that failed, and even with minimal charge, that was enough to start the vehicle - at which point the high-voltage system supplied enough power to keep the 12-volt system up, so that I could drive to an auto parts store to get a replacement.

I'm sure you weren't recommending them specifically so much as using them as an example of the concept, but: Drop-off location in a residential neighborhood with a 'shop' that is one of four mailboxes on a recycling shop. Every single 5-star review calls out the owner ("Chris") by name. Every single other review is 1 star. Sketchy as heck.

I got mine back yesterday. Yay! The technician's notes read: "Road test vehicle and verified TSB 20-2219 applies. Removed trans for inspection as per TSB. Split trans case and inspect. Verified pitting final drive and transfer shaft bearings. Found transfer shaft gear wore into the dampener housing. Replaced trans as per TSB 20-2219 and flushed trans cooler. Updated trans strategy and road test." It's going to take a while to get used to it being so quiet again, and to un-train the internal mental grimace of anticipation of the engine turning on at low speeds. It feels like getting a whole new car, so I am quite happy, and looking forward to driving it for many years!

The noise is present when the ICE is on, both when stationary and when moving. No noise when in EV and moving. The dealer called today to say that they got it apart and that it was bad enough that they'll replace the transmission under warranty (I'm still under 80k miles - yeah, I'm a light driver! Hopefully there are many more miles to come...). I am always nervous about talking to people in real life (and I was just so glad it was something that would be covered!) so I forgot to ask for details - I'll ask more when I pick it up.

I've had the same thing happen twice. Both times I initially pulled the wrong fuse, which didn't help - the second time I made a note in the manual on the fuse-box page of which fuse to pull. So it will probably never happen again :)