ATjones

I bought an '01 E39 M5 a few months ago and it's been a dream since. My friend is in the market for a 5 series and loved the power of my car.

He wants to spend about $25,000 and found a few low mileage E39 M5s in that range. But he's concerned about owning a 12 year old M series as a daily. I told him the E39 in general is much, much more reliable and easier to work on than the E60, but he's not convinced that holds true for the M5.

So he's found a few manual 535i in his price and thinks with a simple tune they'll be almost as fast or faster than my E39 M5. But how reliable is the E60 535i? Especially with a JuiceBox tune.

Styling-wise is a toss up. He wants E60 with the Msport body package because he thinks the standard E60 looks like a grandma car. And he thinks the E39 M5 is better looking, but really dated. Interior wise it's obviously the E60, but he hates iDrive.

So really, it all comes down to maintenance. At 134k miles, my M5 has been flawless. What can be expected of the 535i?

seablue550i

Like any BMW they will have their problems. The key is to find one with the lowest miles possible. The 535i with a tune and some bolt ons could probably stay with an E39 M5, but the more you mod the N54 engine the more problems will arise.

biz77

Typical N54 issues are:
Carbon buildup in the intake - typically needs to be walnut blasted every 50k miles. About $800 at dealership or you can DIY with chemicals and brushes. Figure 5-8 hours.
Oil filter housing gasket leaks. Easy DIY.
When tuned, they eat spark plugs regularly - like every 10-15K miles
If the fuel system has been updated to newest high pressure pump and injectors it should be solid. If it's running on older hardware, it will probably cause issues. BMW has extended the warranty out to 10 years/120K miles on these components.
The ZF 6HP21 (6HP19TU in BMW lingo) transmission is known to leak at the mechatronic sleeve. If you do this repair with a fluid and pan/filter change it is a $200 - $350 DIY depending on where you get your parts and which fluid you use. Dealer will probably be about $800 for the job.
PCV system can become clogged. Oil catch can helping this is debatable. I would replace the stock PCV with Rob Beck Turbos option. It's cheap ($45) insurance.


Beyond that, the cars are pretty stout. Quite a few guys running completely stock engines on big single turbos making up to 750 WHP. Most of them report the cars to be at least as reliable as when they were stock.


No question that a 535i can be tuned well beyond an E39 M5's capabilities. Just a basic tune on pump gas isn't quite going to do it, especially as speeds climb, although it might be a very close short sprint shootout.

zach1328

I disagree with the statement "the more you mod the n54 engine the more problems will arise." Its a pretty reliable engine and the mods will certainly increase the maintenance required, but doesn't really affect overall reliability. Its got forged internals for a reason!

A tuned n54 will burn through plugs and ignition coils and will also have carbon build-up issues quicker. Those are all things I DIY so its not a big deal IMO.

My '08 535i has been a phenomenal car. Only issue so far was the water pump at 51k miles, but water pumps are an issue with just about all Bimmers. My '07 335i with the n54 has also been a great car thus far.
I do believe a tuned n54 will give the e39 m5 a run for its money. A tuned n54 with a DCI thats also running e85 gas will probably pull a few car lengths on the m5. A FBO 535i would likely dust your e39 m5.

seablue550i

Dont get me wrong the engine itself is great, although I do not this it has forged internals! That debate has been going on for some time. Its the parts connected to the engine that fail. I have 3 friends with fully modded N54s and they are in the shop every other week. They will definitely pull a E39 M5 if built correctly but like you said your coils, plugs, charge pipe etc will start to break down. Not to mention they need a walnut blasting every 30k miles on that much boost.

KyleB

I'd buy an E39 M5 over an E60 535i, but that's just me. Definitely more reliable, infinitely more special.

Booyaazaa

Both cars are great and I would love to have a E39 M5. However the issue is when you have individuals trying to tune their N54 for max power without making sure the normal maintenance is done. Also having a decent understanding of how their engine works is essential to you making correct tuning decisions. Yes the first 6 months I had my car I burned through my injectors and plugs however it was due to me running too lean. After I actually spent time learning and doing research, not trial and error, I have had no issues for the past 1 1/2 year running a e30-40 fuel mix, a custom cobb map running 17-18 psi, and everyday I go WOT at least 2-3 times. Also I average 22k miles a year on this car. The only deviation in normal BMW maintenance I do is oil change every 7500 miles. My car is now at 81k miles and running strong. Just my .02 cents.

tpaxadpom

Where did you get the part that E39's are more reliable than E60s? Perhaps you meant to say E60 535i

Personally for daily driver I wouldn't get neither one. Both cars are expensive to maintain and if he is in the mods 535i will cost him as much as e39 M5 in maintenance.
M cars are not daily drivers unless his is abscessed with racing and need a provocative car.
If he likes the M body kit (I am 100% with him on that) he should definitely get the 550i as it comes with 172 style rims (best looking rims for e60 imho).

As far as I-drive goes. My in-laws bought Benz GL 350 bluetec. It has the navy and 6 or 7 disc changer. It took me a while to figure out how to load a CD!!! The screen is small and plain awful. It is not touch screen and sits pretty low so that you have to take your eyes off the road to be able to see what you are doing (not a big fan of the new tablet glue on style but definitely better than this). Despite being so close to the driver it doesn't have touch sensitive screen. You have to use joystick and buttons to navigate. To load a disc you have to select the disc number and press Accept Disc Load or something like that. Shit load of steps before you can insert the CD and people
blame I-Drive...

PS: M car is an M car. You can make 535i go fast but it won't be an M car. You need new brakes, new suspension, spare set of turbos, pump, new rims/body kit and you won't ever get V10 reliability no matter how hard you try. IMHO. I can see someone going through this headache in 2008-2010 but now in 2014, just buy an M5.

zach1328

I would honestly say reliability more comes down to the luck of the draw. For example, which car was maintained better and repaired on time every time? Yes you can see service records, but if its a broken radiator/water pump - who knows how long the other owner drove around with those issues.

My mechanic at my indy shop actually says he see's more M cars in the shop than he see's n54's. It could be chance. Maybe he has more clients who drive M cars compared to n54's, but before I got my 535i he strongly warned me about the reliability of n54's and M's.
So far both of my n54's have been incredibly reliable and I couldn't be happier with my decision.

In all honesty I would love to add an M to my collection in the near future, but for everyday drivability the e60 535i fully loaded is my weapon of choice. Loads of power, comfortable, great gas mileage, stylish, good handling for such a large car etc.

Actually, the e60 535i only weighs 3704 pounds compared to over 4000 pounds for the e39 m5. The weight difference and age of the 2 cars probably gives the edge in handling to the 535i. Forced induction also has much more power and straight line potential.

I don't mean to knock the m5 in any way, I just honestly think a 535i is a better car than the e39 m5 - at least IMO. The e39 m5 is still a beautiful and phenomenal car it just lacks some of the capabilities the e60 535i (or any n54) brings to the table.
I've had my 535i for ~3 years and purchased a 335i a few months ago. When I was in the market for the 335i I was also considering the e46 m3 as I thought I would like the sportiness. In the end I just couldn't pull the trigger on the m3 - I really absolutely love the n54 engine!

Booyaazaa

If they had the complete Dinan stg 5 setup then it would be a really tight race against a FBO 535i. However the E39 would probably start pulling away at 120 mph unless you have RB's then game over for the E39.