[ajbessinger]

Hi there folks! I've got a 2014 500e I picked up a couple months ago. I've noticed that when I transition between accelerating/decelerating I get a clunk sound. Doesn't make any noise on bumps or anything, just when the transfer of torque changes direction on the motor.
This leads me to believe that it is one of the motor mounts in the car getting worn out. I've tried to take a peek underneath to see what I could find, but I wasn't able to determine which motor mount it is... Has anybody had this issue and might be able to point me in the right direction? The motor mounts for these are pretty expensive, so I don't want to end up buying the wrong one...
Thanks in advance!

 

[Electric Tire Shredder]

Check the CV joints. Those aren't all that hard to check by hand for play.

Check that all your recalls were done, since one of mine was for "bad Locktite" on the CV bolts.

 

[twinturboz]

It is not a motor mount, it is a slack in the drive line pretty normal if you have fair share or miles. If you ever had a higher mile manual transmission car it’s very noticeable as well, you never notice on automatic gassers because there is always a preload from the torque converter that it takes up that slack so it’s there but not noticeable.

 

[Electric Tire Shredder]

Also, much less likely but you never know: Check that none of the front suspension bolts has come loose.

 

[ajbessinger]

Thanks @Electric Tire Shredder and @twinturboz. I just got a chance to put the car on the lift at my work today to take a look at the the CV joints and suspension. Everything seems to be in good order.
Upon turning the wheels back and forth, it seems that it's just slack in the drive train as @twinturboz said. My 500e has just about 56k miles on it, so not really that many miles... I do quite a bit of work on EVs (mainly Toyota Rav4 EVs) and I've never seen drivetrain slack in those before, so I guess it's just a characteristic on the Fiat?
I was also trying to see if I could find a way to check the fluid in the gearbox, but I couldn't find a fill port, or even a drain plug for that matter. Anyone know where those might be located?

 

[Electric Tire Shredder]

It's sealed for "life", for which I think the industry standard is about 15 years.

 

[twinturboz]

Thanks @Electric Tire Shredder and @twinturboz. I just got a chance to put the car on the lift at my work today to take a look at the the CV joints and suspension. Everything seems to be in good order.
Upon turning the wheels back and forth, it seems that it's just slack in the drive train as @twinturboz said. My 500e has just about 56k miles on it, so not really that many miles... I do quite a bit of work on EVs (mainly Toyota Rav4 EVs) and I've never seen drivetrain slack in those before, so I guess it's just a characteristic on the Fiat?
I was also trying to see if I could find a way to check the fluid in the gearbox, but I couldn't find a fill port, or even a drain plug for that matter. Anyone know where those might be located?

It is many miles for a FCA car. Lol this ain’t a Toyota where high grade forged steel bearings used in the axles and gears. Toyota over engineer things as “just in case method” typical FCA car build is “just good enough” method. Mine has almost 26k and it has a ever slight slack only notable when letting go into regen and then immediately accelerated otherwise not noticeable in regular situations.

 

[Electric Tire Shredder]

Thank goodness this ain't a Toyota like the last one I had! It needed a complete engine rebuild before it even reached 50k miles.

 

[twinturboz]

Ever heard the term even monkeys fall from trees? I personally don’t care for boring Toyota vehicles but there is no denying majority of their cars outlast virtually all other cars from most makes. I worked for Toyota for 8 years and 300k was pretty normal amount for a 15yr old Toyota. Land cruiser were the most robust of the bunch we have half a dozen customers who have half a million and won’t give them up. It’s clear Toyota built their empire of clients with their solid reputation.

 

[abenusa]

 

[ajbessinger]

It is many miles for a FCA car. Lol this ain’t a Toyota where high grade forged steel bearings used in the axles and gears. Toyota over engineer things as “just in case method” typical FCA car build is “just good enough” method. Mine has almost 26k and it has a ever slight slack only notable when letting go into regen and then immediately accelerated otherwise not noticeable in regular situations.

The drive unit (and almost all the other HV components) in the Rav4 EV were actually built by Tesla, so it's not really Toyota as far as the whole drive-train is concerned. The Mercdes B-Class also uses an almost identical drivetrain to the Rav4, just with a slightly smaller battery.
Both car's motors are very similar to the earlier Model S "big" drive units, just with reverse cut gears and an added parking pawl. As such, they share the same problems with the early Model S, including eating motor/gearbox bearings, shearing motor splines, and leaking coolant into the motor. So needless to say, I do a lot of motor rebuilds on them, haha.
Other parts that the cars share are the onboard chargers, DC-DC converters, battery coolant heater, and coolant pumps. The batteries were custom built for the cars by Tesla, but used the 2600mah 18650 cells that were used in the original roadster instead of the 3200mah cells like the Model S/X use. Rav4 EV has 41.8kwh capacity, and the Mercedes has ~28kwh capacity.
Of course, the 500e is sort of built in the same way in that the drive-train isn't really Fiat, instead it's Bosch powered. As far as the gearbox itself goes, I'm not sure if Fiat or some other 3rd party manufacturer makes it...

 

[twinturboz]

I was talking about Toyota as a whole not just the RAV4 ev in particular. I know that the ev variant of the RAV4 is sort of a mutt.

 

[FiatCares]

Hi there folks! I've got a 2014 500e I picked up a couple months ago. I've noticed that when I transition between accelerating/decelerating I get a clunk sound. Doesn't make any noise on bumps or anything, just when the transfer of torque changes direction on the motor.
This leads me to believe that it is one of the motor mounts in the car getting worn out. I've tried to take a peek underneath to see what I could find, but I wasn't able to determine which motor mount it is... Has anybody had this issue and might be able to point me in the right direction? The motor mounts for these are pretty expensive, so I don't want to end up buying the wrong one...
Thanks in advance!

View attachment 108622

Hi, I'm sorry to hear this. Please let me know if you plan on visiting a dealership for this concern. I would be happy to open a case for you.

Alison
FiatCares

 

[Electric Tire Shredder]

the ev variant of the RAV4 is sort of a mutt.

Same (in a bad way) for the Toyota I had (corolla-powered MR2 with failure-inducing ultra-low-emission controls added).

Same (in a good way?*) for the 500e, & many others, including eGolf, eSoul, eFit, eFocus, & I think the eSpark was also originally gas-only design.

* Replace "a thousand moving parts" ICE with "one-moving-part" electric drive, from Bosch no less! (500e & eGolf)

 

[twinturboz]

Despite the loss of many moving parts there are thousands of Uber expensive system and subsystem on a ev and hybrid that make them no less expensive to fix nor more reliable I driver gassers for the past 25 years and they have been extremely reliable despite having clocked past 200k on many of them, they do require more frequent service yes but I do all the work myself anyway and learn new things. The verdict is still out for most ev as still out none are 20yr+ old with over 200k common like traditional gassers so I’m hoping it’s all positive but I still a bit of a skeptic.

 

[Electric Tire Shredder]

Oops: My point was going to be that the 500e & eGolf mutts are better than the non-mutt Leaf! (designed specifically as EV)

 

[twinturboz]

Yea but to be fair they were the first mainstream to go at it when no one else was , got to give them kudos for the effort and it wasn’t a compliance car they didn’t have to build it.

 

[Electric Tire Shredder]

Ya I was considering one when there was nothing else available. Now I'm wondering if they're giving EVs a bad rap, since battery life is one of the top concerns of potential customers, along with range, charge time, cost, & believe it or not, poor acceleration!

 

[Enginerd]

Sorry to revive an old thread, but new user/owner here with identical symptoms to ajbessinger. I picked up a 2013 500e with 37,000 miles yesterday and somehow on the test drive didn't notice the clunk when alternating between drive and regen. Unless I am very gentle with the accelerator, there is a pronounced clunk/pop that I struggle to believe is normal. I found you can reproduce the noise when stationary by brake torquing and alternating between forward and reverse. I believe it's backlash in the drivetrain but my attempts to pinpoint the source of the problem have been unsuccessful thus far.

I lifted each drive wheel at a time and applied as much torque to the wheel as I could by hand but couldn't reproduce the sound. Naturally there is backlash, but it feels similar to what I have felt in other vehicles. For a short bit I wondered if it was due to recall 13V358000 regarding loose inboard CV shaft bolts but it turns out this vehicle falls outside of that recall scope. Even so, I used my phone to record them at 120 fps while testing and didn't notice any relative motion at those joints.

I'm still hopeful it's the CV shaft(s) but at approximately $420 each, I'm not too eager to buy replacements until I'm confident that is the problem. I can remove the old ones but even then I am not confident I will be able to locate the source of the noise. From the brake torquing experiment, I get the sense a fair amount of torque is required before a clunk or pop is encountered. Perhaps that is why when I attempt to rotate the CV shaft by hand, everything feels tight.

If anyone has any suggestions on what else I could check, I'm all ears. I was surprised to find this thread is the only mention of such a problem I could find on the internet.

Here is the new girl at the watering hole minutes after purchase. While I'm not a big fan of white on white, it should be a best case scenario during a Phoenix summer.

 

[Electric Tire Shredder]

Aren't the CV joints replaceable by your local driveshaft shop? (for MUCH less than $400/side)