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To turbo, or to not turbo

  • You bet. Zoom zoom turbo love!

    Votes: 57 70.4%
  • No, rather have the more proven reliability of the 530xi.

    Votes: 24 29.6%
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Discussion Starter · #1 ·
I'm trying to decide between a 2007 530xi and a 2008 535xi.

One of my main concerns is the reliability of the new turbo engine.

I'd be less concerned if I planned on owning it for less than 4 years, but I may want to amortize the cost of the car over a longer period of time.

If you were planning to keep your 5-series for about 7 years, would you buy a turbo?
 

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Discussion Starter · #2 ·
By the way, I've heard that replacing turbos after they fail is pretty expensive.

Anyone care to guess a ballpark estimate for how expensive it might be to replace?
 

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Love the 'Fest
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There are no guarantees with either engine. The turbos have not been around long enough for anything but a guess as to how they may do relative to the non-turbo engines. Get the car that makes you the happiest and buy an extended warranty if it will make you worry less.
 

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ED Retires Urges!
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IMO--and that's all it is, a general sense--turbochargers have just begun to recover from what has been a very bad rap in the US automotive scene.

The last domestic love affair with turbos was many technological generations ago. Hampered by reliability concerns, turbo lag, high insurance, etc., turbos faded from view and became the province of big diesels, while the US market focused on NA engines with bigger displacement

Since then there have been many advances both in turbine bearing design, engine design, and air-fuel management. Mapping that was difficult with carburetors became a cinch with MAF sensors, port fuel injection, and O2-sensor feedback. What's more, all of these developments have received extensive testing in overseas markets where displacement taxes encourage designes with high specific output.

When my USDM Nissan SR20DE died (due to my own carelessness) I grabbed a front clip turbo (DET) version from a JDM U12 Bluebird. It's the same block w/ slightly lower CR, essentially a drop-in swap, and it features a Garrett T25 gated at 7psi and a top-mounted intercooler.

Turbo lag is present, but given the fat power-band of the SR20 it isn't much of an issue unless you're at high altitude. Tuners understand a hell of a lot more today about mating intake compressors and exhaust turbines to a specific engine design. One company offered a hybrid turbo for the SR20 that was essentially a T28/T3 on the exhaust side--well-suited to a 4-banger--but which had a T04B- or E-type compressor wheel on the intake section.

That's big-diesel territory, and the setup flowed enough air to extract 400+ HP from 2.0L, achieving high levels of boost without cavitating and heating the intake charge to a fare-thee-well as you'd do if you tried to push a tiny stock turbo above 1 bar. And because the smallish exhaust turbine spooled quickly, it wasn't plagued by lag any worse than stock. The main problems were shoehorning the huge turbo housing into the cramped engine compartment, keeping the drivetrain from blowing apart, and managing the horrendous torque-steer once you figured how to put all that power to the ground. :D

Since I had no hood scoop, I made big plans to install a nice bar-and-plate front-mount Spearco from that same kit, but became too lazy to do it once I managed the engine swap. So since 2000 I've lived with the stock T25 @7psi, an underhood 'interheater', and crappy 91-octane gas. Even such foolishness has not sufficed to kill this engine...it took a @#%$ local "mechanic" who failed to refill the radiator :mad: to even attempt that, and he did not succeed.

And this is 15-year-old turbo tech I'm talking about here. The N54 may have kinks to work out, but I bet it won't be because of any inherent unreliability of turbos per se. I'd be very surprised to see properly maintained turbochargers fail, or a modern engine design that couldn't handle the power output.
 

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I hope to keep mine for 7-10 years, and went with the turbo, no question. The power is just too much fun :) And if it gives me maintenance headaches, at least I know it's to maintain something I've enjoyed.

Blew away a V70R this weekend :) I think mostly he just wasn't prepared for what he was up against!
 

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It's a somewhat different animal, but my 2000 Audi A6 2.7T has twin turbos (in a V6), and while the car has been very expensive to maintain, I've had no problems with the turbocharging. Hope I'm not jinxing myself, as I'm taking it in for scheduled service tomorrow :).

Jim
 

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My other car is a 2002 Audi Allroad 2.7 T twin turbo 60K miles no problems with turbo so far. I did buy an extended warranty just in case.
 

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I'm trying to decide between a 2007 530xi and a 2008 535xi.

One of my main concerns is the reliability of the new turbo engine.

If you were planning to keep your 5-series for about 7 years, would you buy a turbo?
I had the same question to answer. I plan to keep the car for perhaps 10 years (I still have my '98 328i sedan, 140k miles and barely broken in). I test drove an '07 530xi wagon and was not impressed with the overall response. It felt underpowered, and it felt heavy. I knew that I would not be happy in the long term with that car. I picked up 535xi wagon in Munich on June 22 and took it out for the day on the Autobahn. It is an amazing car, an amazing engine. V8 grunt with I6 size and weght. The car felt small again, very fast and very nimble. If it were a turbo from anyone else, it would be a concern, but given the amount of testing BMW does with new engine development and their past history with turbos (production cars and F1), it was not much of a concern. The inline 6 has been bulletproof for what seems like decades. Don't worry, be happy!
 

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My other car is a 2002 Audi Allroad 2.7 T twin turbo 60K miles no problems with turbo so far. I did buy an extended warranty just in case.
I have a 2001 ar 2.7T w/75k mi on it. No probs with the turbos either, but it seems that just about everything else has gone wrong with this car. I've racked up over $7k worth of repairs on the extended warranty alone. Nevertheless, this Swiss Army knife of a vehicle has served me well...when it's running.

Spyder
 

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Philosopher-king
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I have a 1998 Volvo T5 turbo with 173,000 miles. It still has the original turbocharger and uses no oil between routine changes. Original clutch, too.

The drivetrain has been pretty good. Everything that's bolted to the drivetrain, like the AC system, the electrical system and the suspension bits and pieces, is another story entirely. But the turbocharger and drivetrain has been amazing. :thumbup:
 

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By the way, I've heard that replacing turbos after they fail is pretty expensive.

Anyone care to guess a ballpark estimate for how expensive it might be to replace?
I'm just picking up on an old thread as part of the car buying research process. I'm keenly interested in the 535i (especially with the M-Sport package available in Canada), but highly skeptical of buying another turbo, especially one from a manufacturer who has virtually no history of gasoline turbo engines (at least in North America) since the 1980's. I'm hoping to find a car that I can own and enjoy for 7-10 years with a high degree of reliability.

My last experience with turbos was owning a 1987 MB 300SDL Turbodiesel that I bought secondhand in 1998. The turbo held up just fine, but the cylinder head cracked at 164,000 miles. $4600 later, I had a new cylinder head, and later learned that Mercedes was on its 3rd cylinder head design revision due to cracking issues, which were exacerbated by turbo boost pressure. Am I correct to presume the cylinder head of the 535i is aluminum (or aluminum magnesium composite)?

Another colleague had the twin turbo crap out on his Audi A6 2.7T...3,000 miles out of warranty. He was unsuccessful in securing any dealer or manufacturer goodwill on the repair cost. His wallet was $4000 lighter after that one.

To the contrary, there are good turbos out there (Volvo and Porsche to name a couple). I haven't seen anything to indicate the 535i has serious trouble, but then again, I'm jaded by my previous experience, and it's only been 2 years...

Thoughts?
 

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I have a 1998 Volvo T5 turbo with 173,000 miles. It still has the original turbocharger and uses no oil between routine changes. Original clutch, too.
Wow. Nice. I also have a 1998 T5 Turbo I purchased new in 1997. :thumbup:; Mine is just 1K shy of 100K miles though. I've had no issues at all with the turbo, and like you - the car uses no oil between routine changes. I have religiously used Mobil 1 for the long run, and I have to believe that has a lot to do with the reliability of the engine and components. No oil leaks, seepage... nothing. And it still runs like new.

I also have a 1996 Volvo 850 Turbo Wagon. Same basic engine. 120K miles there. The original turbo is still going strong. Only issue is a seal on the turbo's oil return line that needs to be replaced more often than I'd like. It seeps oil from time to time.

I'm planning to order a 535i within the week. Given my experience with the volvos, twin turbos don't scare me at all. Of course I have no experience with BMWs, but sure hope the 535i will last. I tend to keep my cars 5+ years.
 

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I already made my choce :D But not for reliability reasons.
Me too - I'm not worried about the turbo at all. There's enough other stuff in the world to worry over, BMW technology is not on my worry list....:)
 

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Turbochargers in the 1908's were considered consumable items that needed to be replaced like brakes, etc. Today they are better designed with better lubrication and materials. Also the industry better understands the need for cooling ( water/glycol and oil), intercooling, piston cooling as well as block and head strenth/durability. In Europe, Turbo diesels are the norm. Turbocharging is the future...the engines keep getting smaller and more powerful.

As with any design and any manufacturer, there will be screw-ups from time to time. I just ordered a 535 and am looking forward to it. Also, it looks like BMW is just catching up to VW... the 535 has 300 hp and 300 lb-ft from 3 liters. VW has had 200 hp and 200 lb-ft from 2 liters for some time. BMW has not embraced turbocharging for gasoline engines (and Mercedes has been using more supercharging) but this trend toward turbcharging is growing. By the way turbos are the only way to go if you live in the mountains!

Both the VW and BMW engines are considered smooth, powerful and class leading.
 

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Sorry...meant to say 1980's
 

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Me too - I'm not worried about the turbo at all. There's enough other stuff in the world to worry over, BMW technology is not on my worry list....:)
Absolutely agree, not need to worry about turbo. Simly because cars with turbo engines are not on my shopping list! :rofl:
 

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VW/Audi have sold hundreds of thousands of 1.8t and 2.0t motors over the last few years. I have heard nothing about turbo failures in these modern engines.
 
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