We have already talked about all the BMW F30 Problems on LifeOnFour, in fact, it is one of our most-read articles. A lot of emails have recently come in demanding that we do a better job describing the BMW F30 automatic transmission problems. So here we are. We will first name the automatic transmission that the F30 3-Series is using and then list all the problems we found online and by talking to local F30 owners and a BMW technician.
What automatic transmission is in the BMW F30?
The F30 BMW 3-Series uses the ZF 8HP. The name of this transmission indicates it is an 8-speed Hydraulic converter with Planetary gear sets, thus the name 8HP. This means that it is a classic hydraulic automatic transmission and not a direct-shift, dual-clutch transmission.
The ZF 8HP transmission is known to be a highly reliable unit, which explains why it is found in vehicles such as Rolls Royce Phantom, the Alfa Romeo Giulia, the Toyota Supra, in RAM trucks and the list goes on. This is always a good sign when researching automatic transmission reliability; proven units are much more reliable than completely new, untested transmissions.
You might think that because it is a standard hydraulic automatic transmission with a torque converter and planetary gear sets that it is much slower than a direct-shift, dual-clutch automatic transmission. Well, you are wrong. The 8HP can handle insane amounts of torque and it also provides lightning-fast and smooth gear shifts. It is so good that you can find it in the BMW M235iR race car where you would normally find a sequential gearbox. You can find the 8HP transmission in multiple versions: the 8HP45 which is fitted to most pre-LCI (facelift) F30s, the 8HP50 (fitted to LCI/facelift F30s) and the 8HP70 which is meant for high torque applications.
Common BMW F30 Automatic Transmission Problems
There really are not many complaints about the F30’s ZF 8HP automatic transmission, however, no transmission is perfect. Here is what we found.
Mechatronic sleeve failure and problems
I had a ZF automatic transmission before and it was notorious for having problems with the mechatronic sleeve. This is essentially a small rubber sleeve that protects the electrical connections of the various electronic components that send and receive data which in return help the transmission operate as it should. When the sleeve fails, automatic transmission fluid floods these electrical connections making all possible transmission errors show up on the dashboard and leaving the transmission in a non-functioning state. There were some cases of this happening on the 8HP so it does not hurt to have the mechatronics sleeve inspected.
Complaints about jerky shifting when it is cold and in sport+ mode
The most common complaint (we would not really call it a problem) is the fact that both the ZF 8HP45 fitted to the pre-facelift BMW F30 and the ZF 8HP50 fitted to the facelift BMW F30 tend to shift a bit harshly when they are cold. This is most noticeable when it shifts from the 1st to the 2nd gear and vice-versa. This is even more noticeable in extreme weather conditions. However, according to BMW and literally 100s of owners, this is considered to be normal and expected.
Strangely enough, by browsing the owner’s forums and talking to our local BMW technicians, many owners also complain about the rough gear changes in the Sport+ mode or when using the paddle shifters. The fact of the matter is that insane shift speeds can only be achieved with a little roughness that goes along with it. The transmission simply cannot stay as refined and comfortable as it is when not using the sport mode.
Transmission problems due to a faulty xDrive transfer case
Many owners with xDrive-equipped F30 3-Series BMWs face problems with jerky and hard shifting. This has been an illustrious problem as no one suspected that xDrive transfer case problems could lead to automatic transmission problems. It was later discovered by many owners that a faulty transfer case was in fact causing the problems and some owners also started seeing the ESP light come on as the car changed gears and could not handle the torque.
Replacing the transfer case under warranty resolved the jerky and hard shifting problems. Some owners, with cars that were not under warranty, opted for the X-delete modification kit which means they lost the X-Drive AWD functionality but they regained smooth gear shifting.
Transmission problems due to an off-balance XDrive front driveshaft
While we cannot confirm this, we still think it is worth mentioning based on the few occurrences we saw of this “theory” on F30 forums. BMW F30s with xDrive might also experience automatic transmission shifting problems due to an off-balance front xDrive driveshaft.
8HP45 Solenoid failure
While talking to a local BMW technician we also got information about faulty shift solenoids that affects the 8HP45 automatic transmission that was fitted to the pre-LCI F30 3-Series BMWs. Apparently, ZF, the manufacturer of the 8HP45 transmission did a recall on the factory shift solenoids which major car manufacturers that use this transmission decided to ignore (this includes BMW). When the solenoids fail, the control module of the transmission tries everything in its power to adapt the transmission operation back to normal. It does this by increasing the pressure map that forces gear engagement and it increases the latency which enables the correct engagement time. Because the control module cannot completely adjust the shifting pattern due to faulty solenoids, jerky and hard shifting become a much bigger issue. In this F30 forum thread, there are 2 owners who solved all their issues by having the shift solenoids replaced. One of them was quoted insane amounts of money to have the torque converter and other transmission components replaced. Replacing the ZF recalled solenoids solved all his issues with hard shifting. Ignoring these BMW F30 Automatic Transmission Problems with hard shifting and jerky gear shifts can lead to major transmission problems.
While the F30’s 8HP 8-speed automatic transmission is not known to have many oil leaks, one is worth mentioning. The 8HP uses an external ATF cooler which keeps it cool while driving in sport mode or simply beating the stop-and-go traffic in the summer heat. The inlet and outlet connections are sealed by two O-rings. And as you can imagine, the heat that travels past those o-rings slowly but surely destroys and deforms them. As this happens, you get fluid flowing past the o-rings which leads to transmission fluid leaks.
Things To Know And 8hp Transmission Maintenance
F30 ZF 8HP transmission maintenance
ZF, the manufacturer of the 8HP transmission that is in the F30 BMW dictates a replacement of the transmission fluid every 50,000-75,000 miles (80,000-120,000 kilometers) or eight years if you don’t cover as many miles. We would recommend sticking to the lower part of that range especially if you like to drive in Sport+. The transmission fluid suitable for this transmission is the ZF LifeGuard Fluid 8. Previous versions (6,7) are not suitable for the 8HP!
When replacing the ATF, you should also replace the filter which comes integrated with the plastic oil pan.
Our local BMW technician also warned us about another common misconception about the transmission fluid change on the ZF 8HP transmission. According to him, many dealerships and independent mechanics will only drain the transmission fluid that comes out from the drain plug and after removing the plastic oil pan. Even though ZF does not recommend removing the oil cooler lines and draining the old transmission fluid from the oil cooler and the torque converter many people, including my local BMW dealerships, do so. By removing the return line from the oil cooler and running the engine, you are able to push out old transmission fluid which is captured in the torque converter. By doing this you remove almost 90% of the old transmission fluid as opposed to 50-60% of the old transmission fluid by following ZFs recommendations. Again, do not do this on your own as it is not an approved procedure and should only be left to professionals with experience. We do not condone nor are responsible for your actions as they can lead to a complete transmission failure.
Towing an F30 BMW with an automatic transmission
Let’s say your F30 3-Series with an automatic transmission decides to break down due to a dead battery or some other reason. The first problem on your hand is the fact that your transmission is stuck in Park. Most vehicles with an automatic transmission have a neutral safety switch hidden somewhere around the gear selector lever. But no, not the 8HP. To engage the neutral safety switch and disengage the parking pawl that is keeping the car in place, you must thread in a small bolt placed on the driver’s side of the 8HP transmission. You can check the exact procedure here. If you can do this while at the side of the road, make sure the car is being towed correctly to avoid transmission damage.
Frequently Asked Questions
Is the ZF 8HP a dual-clutch automatic transmission?
No! As the name suggests 8-Speed (H)ydraulic (P)lanetary gear automatic transmission, the ZF 8HP is a standard hydraulic automatic transmission.
What is the ZF 8HP torque rating?
The torque limit depends on the transmission variant:
ZF 8HP45 (found in pre-LCI F30s): 450 nm (332 lb-ft) torque limit
ZF 8HP50 (found in LCI F30s) and 8HP51: 500 nm (369 lb-ft) torque limit
Is BMW F30’s ZF 8HP automatic transmission reliable?
Yes, based on all the research we have provided in this article we would say the ZF 8HP and especially the second generation ZF 8HP50 is one of the most reliable standard hydraulic automatic transmissions on the market today. With regular servicing, it will easily last 200,000+ miles.