5.0 vs. 3.5i Complaints/Reliability

[Poppyboy]

It seems there are a lot more complaints on here about 5.0 issues vs. the 3.5i. Is that simply because there are more 5.0 enthusiasts on here, or is there clearly a difference in reliability? Obviously, there are more complicated components in the 5.0's engine and other components to go wrong, but I would think many other components are similar. Maybe not. I'm just trying to get some feedback here from everyone.

[mitch808]

If you want power, there is no question, the bigger engine is the way to go. There are also more options from the aftermarket in this regard.

I have the 6cyl, and like it, but at times wish I had the 8cyl... No serious issues thus far, and it's also a common platform engine used on the 1 and 3 series at one point. Good 'ole N55... Hated on by most everyone ;-P

[Poppyboy]

Thanks. Part of my motivation for asking these questions is because I'm considering a 5.0, but am unwilling to significantly compromise reliability. For example, my 3.5i burns no oil. However, I've read many complaints about oil burning in the 5.0. Sure, twin turbos make a big difference over one turbo, but I feel in this day and age, oil shouldn't burn in these cars. It's not like turbos and piston rings are new concepts...

[mitch808]

Just recently, I went from oil being full to half, and when I actually noticed it going to half, it was at the low mark within a week.... I just topped off a full qt this past weekend, and am going to track it over the coming weeks... So that was new for me, and not something I expected.

Beats my other car that burns about 1qt every 600-1k miles.

[Poppyboy]

If that happened to me, and my car was still under warranty, it would be at the dealership without delay. That's an insane amount of oil to lose.

[SteveMD]

50i here. Do about 12K a year. It takes a quart every 6000 ish. No biggie.

If you're on the fence and can afford to run a 50i (MPG is not stellar), go with it. It's the most fun you will have in a big vehicle.

[Poppyboy]

Originally Posted by SteveMD

50i here. Do about 12K a year. It takes a quart every 6000 ish. No biggie.

If you're on the fence and can afford to run a 50i (MPG is not stellar), go with it. It's the most fun you will have in a big vehicle.

Thanks! Aside from burning one quart per 6k-ish miles, any major problems?

[boogakb24]

Originally Posted by Poppyboy

It seems there are a lot more complaints on here about 5.0 issues vs. the 3.5i. Is that simply because there are more 5.0 enthusiasts on here, or is there clearly a difference in reliability? Obviously, there are more complicated components in the 5.0's engine and other components to go wrong, but I would think many other components are similar. Maybe not. I'm just trying to get some feedback here from everyone.

You sure there are more 5.0 enthusiasts here than 3.5??

[SteveMD]

Originally Posted by Poppyboy

Thanks! Aside from burning one quart per 6k-ish miles, any major problems?

Nope. And I'm running a mild tune. I have had battery problems but that is common to all BMWs it seems.

[Poppyboy]

Originally Posted by boogakb24

You sure there are more 5.0 enthusiasts here than 3.5??

For postings about reliability issues, it certainly seems so.

[Cattivo]

I have the 50i and have not had any problems except for a few speeding tickets ever since I installed the JB Stage 1 tune...I've added 2 quarts of oil in the 3 months I've owned it but that's from lots of spirited driving. I test drove a handful of 35i's and there's just no comparison to the 50i in terms of power and the sound of the N63 vs the N55 especially on a cold start. The 50i only gets a few less mpg compared to the 35i

[///Mpower///]

Very trusted friend and long-time BMW mech says the 5.0s are far far more problematic that the 3s. That goes for the cars as well as the SA/UVs.

[3X3=5]

I bought my 2012 50i with 43K miles a little over 3 months now. It's been to the dealer 3 times already. It's there right now (day 10) for the following:

Starter being replaced
Front thrust rod bushings
Oil leak from the non return valve
Rear seat heaters don't work
And a few other miscellaneous/non-engine related issues

When I bought it, it went in for front window regulators failed (2 trips - one to diagnose and a return trip after parts came in).

Before I bought, service records show the following repairs:

AC evaporator leaking
Fuel injector leaking
Vacuum pump leaking
High pressure pump HDP permanent malfunction
Engine breather lines leaking
Vehicle battery permanent failure
Oil sump gasket (V-engines) leaking


Probably 3-4 of those issues are specific to the V8 engine. This is my first V8 BMW and the only reason I ended up with the 50i is because I had to have M Sport package in carbon black with a select set of features. This one came up with all that I wanted and outstanding condition so I went for it. Before I bought it I called a few shops that specialize in BMW and spoke to my service advisor and all of them said yes, you will see more problems with the V8. I was willing to take that chance, but I spent $3200 on an extended warranty (even though the car is under factory warranty for another year+) with excellent coverage. From what I was told, it's not that you'll run into a lot of problems necessarily, but if you don't they'll be very expensive to fix. From the history and my experience so far, I'll need it.

BMWs have a fair amount of issues in general, the V8 just adds another layer.

[goodmaj]

Originally Posted by X5Mer

Very trusted friend and long-time BMW mech says the 5.0s are far far more problematic that the 3s. That goes for the cars as well as the SA/UVs.

Same thing here. I came out of an MB e550 before my X5 and before the MB I had an e39 M5, so originally I was all over the v8. However, I called my version of the "friend and long-time BMW mech" who said avoid the v8s like the plague unless you enjoy bringing the car in every few months or so. I heard the same from a few other people.

That said, I'm sure there's plenty of people on this board who run v8s with little or no problems.

Oh, and as for the 3.5 wrt reliability....I got mine about a month ago. Noticed a vibration when turning at very low speeds under acceleration. Hello new transfer case! Good thing it's still under 4/50....

[MRV99]

I have owned BMW V8's what feels like forever now and I have not had "V8" engine issues. I have had BMW components which are on i6 and v8 issue but nothing v8 specific

Here are my V8 experiences

I have always changed my oil twice as much as what BMW states. Never more than 7500 miles per. My v8's have always burned some oil. The v8TT's are thirsty, BMW states 1qt per 750 is acceptable based on specific driving conditions. I am at 1qt every 2500-3000

All BMW's are having high pressure fuel system component issues. Injectors and pumps on i6 and V8 have issues.