inline6 e320 vs v6 e320 - preference ?

[cgranju]

On a fast learning curve here, I see potential advantages to both cars. I'm looking at purchasing one of several '96-'97 E320s or one of several '98 E320s. All have about 100K & reasonably good service, records, etc. So, all things being generally equal, which is a better bet for providing the kind of good, long-term service one should expect from a well-maintained MB?

From a tech standpoint, is one or the other engine particularly easier to diagnose & do maintenance on?

I had wonderful luck with my '71 220D (350K +) & '81 300TD (240K), both as running cars with life left in them...but this will be my first gasoline MB.

thanks in advance
-c

[suginami]

My preference is with the inline-6 over the V6, but that's just me.

One thing to consider with the inline-6 is that early M104 engines had problems with oil leaks at the head gasket.

The head gaskets were updated several times, but I don't know when the last update hit.

'96-'97 E320's may never need a head gasket.

I don't think the V6's ever had head gasket problems.

Another consideration is that the '96 had the 4 speed transmission, which proved to be quite durable and is cheap to rebuild.

'97 was the first year of the 722.6 5 speed auto, but it required a lot of updates. 2000 models have all the updates needed.

[cgranju]

Are these head gasket failures to the extent that they would be warrantied or even covered in a recall (post warranty...i'm guessing i'm on my own, but i'm also an experienced DIYer w/ most of the right tools + friends who have good diagnostic equipment & service manuals).

I'll be writing the check (if) only after a final consult with all the maint. records, so thanks for the heads up there.

I'll also be in the market for a CD changer if I go for the '96, but I guess that's another thread for another day....

From other stuff I've read, sounds like the '96 is more of the traditional 'tried & true' MB mechanicals....thus perhaps a bit kinder for the DIYer to own.

[deanyel]

A head gasket is child's play compared to having your rings go bad on the V6, which seems to be quite common. What can you say about an engine (V6) that requires synthetic oil to operate properly - crazy.

[manny]

Originally Posted by deanyel

What can you say about an engine (V6) that requires synthetic oil to operate properly - crazy.

How did you come up with that fairytale ?

That V6 needs synthetic to operate under (at the time, MB-specified) FSS a.k.a. extended oil change intervals.

AFAIK, dino oil is fine in that motor if you change every 5K or thereabouts.

[manny]

And that's the way it is.
If you change oil as per FSS.
That does not mean a V-6 will not run " properly " on dino oil.

[cgranju]

well, fwiw, i figure i'll go ahead and change the oil every now & then

[suginami]

Originally Posted by cgranju

Are these head gasket failures to the extent that they would be warrantied or even covered in a recall (post warranty...i'm guessing i'm on my own, but i'm also an experienced DIYer w/ most of the right tools + friends who have good diagnostic equipment & service manuals)

No, no recall of the head gaskets, but the problems were mainly on the earlier M104 engines ('93-'95). There were surely some '96 E320's that had head gasket leaks if I had to guess.

My 1993 300E (3.2) "E320" had the original head gasket up until about 127,000 miles. It developed a leak at the right rear corner of the head gasket, which is where they usually leak. I let it just leak for about a year, but it got so bad that it leaked on the exhaust manifold. When my mechanic had it up on the lift, the whole under carriage was covered in oil.

In any event, these head gaskets fail so that oil leaks externally. It's not a failure where the coolant mixes with the oil, causing other problems.

So look for a leak. If it's not, it either means it's been changed or it might not ever leak.

[suginami]

Originally Posted by cgranju

From other stuff I've read, sounds like the '96 is more of the traditional 'tried & true' MB mechanicals....thus perhaps a bit kinder for the DIYer to own.

Truthfully, the only material difference between '96 and '97 cars is the transmission.

The 5 speed auto in the '97 has advantages in that you get slightly better mpg, probably faster acceleration, etc., but it is an electronically controlled transmission. You need to have codes pulled to diagnose problems, and my mechanic can get these transmissions rebuilt for $3,500, installed.

The older 4 speed auto is cheap to rebuild. He installs rebuilt units with a one year warranty for $1,500.00.

[deanyel]

Originally Posted by manny

How did you come up with that fairytale ?

And got it from the factory, see http://www.whnet.com/4x4/oil.html and the FSS lawsuit, didn't even think it a provocative or controversial statement. That the 112 engine family is a substantially cheapened engine comes from Mercedes itself in statements made to Wall Street at introduction. And some of these ring failures are coming on cars that have never seen conventional oil.

[BMG]

Head gasket tattle tale

The leak is often missed in the engine compartment since the oil rarely comes out when the engine is sitting. Look under the car and if there is oil staining on the underside of the the passenger side of the car then its beginning to leak. The oil will leak when driving - it runs down the block and hits the airstream under the car and mists the body.

Think of the guy chewing and spitting tobacco driving down the road in his white convertible cadilac. The interior looks great, but that driver side door is a mess.

[TimFreeh]

Originally Posted by deanyel

And got it from the factory, see http://www.whnet.com/4x4/oil.html and the FSS lawsuit, didn't even think it a provocative or controversial statement. That the 112 engine family is a substantially cheapened engine comes from Mercedes itself in statements made to Wall Street at introduction. And some of these ring failures are coming on cars that have never seen conventional oil.

The M112 engine was cheaper to build as I recall however I have not heard of more than a handful of ring failures on the M112/M113 engines. Of course thats not very comforting when you are facing the costs of replacing an M112 engine with shot rings. One of the moderators on this site (Zeus) is currently facing this issue on his otherwise perfect E430. The car runs flawlessly but burns oil at an excessive rate.

As others have pointed out the M104 faces headgasket, wiring harness and ETA motor issues - overall I'd say the M112 has proven to be better long term bet than the M104. I know of several M112 with 200-300K that have had absolutely nothing done to them other than routine maintenance, I think you would have a hard time finding an M104 owner that could have dodged the headgasket, wiring harness and ETA motor bullets over the same time periods.

On the road I slightly prefer the M104, you can't beat a straight six for smoothness.

[POS]

I've owned both - the V6 is smoother, has better power, and gets better mpg while being a relative trouble-free engine (no headgasket leaks!). The V6 is the winner to me.

[cgranju]

wow - i realize my question was like driving up to a bar in Texas & asking which is a better truck, Ford or Chevy. I'm leaning heavily towards the L6 (that's W104? ..i've gotta learn the models) more due to low mileage, impeccable interior condition, full maintenance records with a single PO, potential transmission higher longevity/lower R&R cost, and general "honest car" condition. The '99 MY is about the newest I would be able to go financially as I live by a cash-only car purchase philosophy & at that tend to devalue any & all practical cars to be never worth more than about $7-9K (fun, heavy maintenance antique/sports cars are worth more in my twisted mind!).

Thanks for the input, folks. I'm sure I'll be reporting back with my findings and hanging around in general to absorb tech info.