2003 bmw z4

[e90328isf]

Hi, I am looking at a 2003 BMW z4 with 48K miles on it. The car has the SMG transmission.

The car has a few issues:
broken passenger window regulator
worn front struts - I am guessing they are worn all around
Valve Cover Gasket oil leak

I am wondering what are other common problems for these cars - specifically wondering about the transmission

thanks

[Sterling Roadster]

Originally Posted by e90328isf

Hi, I am looking at a 2003 BMW z4 with 48K miles on it. The car has the SMG transmission.

The car has a few issues:
broken passenger window regulator
worn front struts - I am guessing they are worn all around
Valve Cover Gasket oil leak

I am wondering what are other common problems for these cars - specifically wondering about the transmission

thanks

If you want to go really in depth there are a few articles about all the little problems these cars have. Search E85/E86 issues and you will find plenty. For the major more serious ones take the car for a drive and test all functionality. If the steering feels weird it may have the known "sticky steering" issue. Which is a pain and potentially expensive. Window regulators go sometimes, not really a huge deal. Seems early for failed suspension but it happens with age I supposed. Valve cover gasket is a few hundred bucks and the most common for an M54.

The big one to pay attention to is the SMG transmission. I would at least want a good indy to scan for trans codes and do my best to make sure the pump is not going to go out. If it does, it's very expensive. You would be better off doing a manual conversion at that point. Make sure the top works properly, if it's powered that can get expensive too.

Other than the SMG transmission these are relatively low risk cars. Many components shared with the 3-series so parts are easily available. The engine is a peach when taken care of, kind of a work horse. Good luck and let us know how it goes!

[Huz-Z]

The roof motor is located where it can be flooded with water from the roof drains and fail. Check that the roof opens and closes quickly and smoothly. If the car has a manually operated roof then that’s one less thing to worry about.

I should add that the roof motor can be relocated to the trunk to avoid a failure and that it may be possible to repair a failed motor and save on the cost of a new one. Others have used top motors from Ford Mustangs - motors made by the same company. Lots of threads here on this.

[T-Bears]

I got the sticky steering wheel it can be annoying but that's the least of my Z4 problems for now. From what I remember the wiper motor can have grease on the electrical contacts, so I had to remove the wiper assembly just to clean up the grease and poof the wiper blades are working. Front bushing might need replacement. The window regulator takes a bit of time and patience but well worth it to fix yourself. It seems to be a common issue I had to replace my driver side.

Other than the flimsy interior plastics that will nickel and dime you to death j/k...the auto transmission is something to look out for. I'm not sure about SMG but some ZF5HP19 transmissions have 3rd gear flareups when the fluid heats up specially on hot days. Possible F clutch drum issue.

I have a Z4 2.5 Sport and it loves to burn and leak oil compared to my SLK with higher mileage lol. Ive replaced every seal except the one sandwiched between the oil pan and block and that's where it leaks.

The 48k mile Z4 you're looking at should be problem free for a while but like Sterling Roadster mentioned, have scanner on hand so you can see if the transmission is clear from codes.

[Slalom]

The valve cover gasket takes a little time but is not terribly hard to do. I think that the BavAuto YouTube video is still up.

The long hood on the Z4 makes it easier to replace than on a 3 series. - you can get to everything without dismantling a lot of unrelated stuff.

Careful not to break the cover. On cars that run hot like the twin turbo E92 they tend to crack. My E85 was no issue.

[Gamb1t]

The only unique area for your Z4 example is the SMG transmission. It was considered one of BMW's less than stellar implementation. It's not the same SMG found in the e46 M3 either. IIRC the pump is expensive if it were to go (which is almost a given).

Everything else is normal Z4 maintenance/repair.

[86Zed]

Originally Posted by e90328isf

Hi, I am looking at a 2003 BMW z4 with 48K miles on it. The car has the SMG transmission.

I am wondering what are other common problems for these cars - specifically wondering about the transmission

It's nearly a 20 year car and is likely due for a number of belt, pulley, bushing, and suspension related services. Keep that in mind depending on how you plan to use it