Hello guys and welcome to mattsbeamer. I've decided to create informational videos on the F20 F21 1 series when it comes to buying a 1 series. I created an N13 engine video the other day, which seemed to be popular. So if you want to know what to look out for on an F20/F21 let me know.
Today I will be focusing on the 8-speed auto transmission, which is known as the ZF8HP, which is built by the ZF group which stands for Zahnradfabrik Friedrichshafen. The 8 in the code name refers to the number of gears the gearbox has, in this case, 8. The ZF8HP took over the role of the famous Zf6HP, which was their 6-speed box. HP stands for Hydraulic converter and Planetary gearsets.
The first car to use the 8-speed box was BMW, with the brand new BMW f01 760Li, which was their flagship V12 back in 2008. Since then so many manufactures used a variant of the ZF8HP, such as Alfa Romeo, Alpina, Aston Martin, Audi, Bentley, Chrysler, Dodge, Haval, Iveco, Jaguar, Jeep, Lamborgini, Lancia, Land Rover, Maserati, Dodge Trucks, Roll Royce, Toyota, Vinfast VW and most of the BMW range. So it can be paired up with a little engine like the engine in my 116i 1 series up to a big V12 Roll Royce.
Saying this, each gearbox will have differences to handle different amounts of power.
I believe that the early F20s had the ZF8HP45 which could handle up to 450nm of torque 450nm on petrol cars and 500nm on a diesel car, while the LCi models had the second generation ZF8HP50 which could handle up to 500nm on petrol and diesel cars. The second generation came out in 2014 and the 3rd gen was released in 2018. Sorry if I'm getting a bit boring.
What to look out for when buying one.
These gearboxes are very good, to be honest.
When putting the car from PARK into any gear it should react very quickly, there should not be any hesitation, noises or and sudden jolts it should be smooth like butter. I recommend when looking at buying one, that you put the car in all the possible gear situations when standing still.
When driving, you should test the gearboxes out in all possible modes. It should change gear effortlessly and with no hesitation, jolts etc. Also, test the car in manual mode.
If the gearbox does start changing gears a bit rough, it could be due to the car's system learning the way the driver has driven, sometimes resetting the values in the gearbox can sort an issue with the gear change.
I would avoid gearboxes which are making any whining noises, they should not make any noises at all. I have heard of gearboxes being replaced on warranty.
If you can, I would recommend that you get someone to check around the gearbox for leaks.
Servicing.
As far as I know, BMW says that the gearbox is a seal for life box which doesn't need servicing. But what I understand that as, is life is 100000 miles, as no matter how great the oil is, no oil can last for life.
I believe that a few sources recommend changing the oil every 60,000 miles, so it is worth asking if your box has had its gearbox oil changed. I don't think BMW will perform this job themselves, but a decent specialist will.
If your car has done over 100000 miles with no servicing, then changing the oil can do more harm than good. The best people to chat to is the ZF specialist, if they don't know, then no one will.
The oil used is called ZF Lifeguard Fluid 8, which isn't cheap, but it's so much cheaper spending money on a decent service than a new gearbox. Oh, make sure you only use the fluid from ZF. Automatic gearboxes are very sensitive to wrong fluids.
I may show how to change the oil on mine in the future, if I keep my car, I've only done about 25,000 miles at the moment.
I hope this video was of some use to you, if you want to know about a certain engine or other importing areas, let me know :)
