Do any 335 motors have forged internals??!!

[Stratman335]

This is a big topic on the Internet and I've read about how people have had the motors opened up and confirmed forged internals on n54 motors but...
I've also read about how many say the opposite.

What s the truth???

[e66man]

I think the biggest debate is the pistons since we know that the crank and rods are forged. I understand there was a piston part number change back in 08 or 09 that led some to believe that they went from forged to hypereutectic or other. I haven't seen absolute proof in the matter though. There is a long thread on this forum somewhere talking about it.

[Stratman335]

you can confirm that the rods are forged also?


I think the biggest debate is the pistons since we know that the crank and rods are forged. I understand there was a piston part number change back in 08 or 09 that led some to believe that they went from forged to hypereutectic or other. I haven't seen absolute proof in the matter though. There is a long thread on this forum somewhere talking about it.

Well I spoke to my service rep and he told me its highly unlikely that they're forged although he will get an answer for me by tomorrow so the wait will be over soon enough

[e66man]

you can confirm that the rods are forged also?



Well I spoke to my service rep and he told me its highly unlikely that they're forged although he will get an answer for me by tomorrow so the wait will be over soon enough


There is actually BMW literature somewhere stating the crank and rods are forged, but spoke nothing about the pistons. Either they already knew they were changing to non-forged when the document was written, or they never were.

To answer your question, yes, I can confirm with no evidence whatsoever that the rods are forged. :)

[smc850ci]

I can confirm with no evidence whatsoever... :lol

[Stratman335]

My Service guy called me today to give me the answer but I missed the call and he just left me a voicemail to call him back.
Problem is I have to wait till Monday to get the official verdict.

My guess is that they're not and my personal assumption is that car companies are try desperately to cut costs like crazy in order to maximize profits and that includes manufacturing many parts in poor regions like china, Mexico etc..

Just look at all the mustang transmission problems ( china)

I doubt we have all forged internals

[Stratman335]

I spoke to my SA yesterday and he said he confirmed that ALL the internals are cast.
I asked him if he was 100% sure the rods, pistons, crank were not forged and he was very adamant in his initial response.

So there you have it , this debate is officially over or is it....

[e66man]

Again, the crank is most definitely forged, as indicated by the attached BMW training document.

[Stratman335]

Again, the crank is most definitely forged, as indicated by the attached BMW training document.

Just left my SA a voicemail and waiting to see what he has to say about that.

[Pyewacket69]

Just left my SA a voicemail and waiting to see what he has to say about that.

Just checked my Bentley manual on this subject, and it states the following on the N52, N52KP, N51 & N54 engines (page 010-11):

Connecting rods/Crankshaft: Forged steel (Cast Crank).

[Stratman335]

Just checked my Bentley manual on this subject, and it states the following on the N52, N52KP, N51 & N54 engines (page 010-11):

Connecting rods/Crankshaft: Forged steel (Cast Crank).

Ok so the rods and crank are forged ?
What about the pistons ???

[Pyewacket69]

Ok so the rods and crank are forged ?
What about the pistons ???

The way I understand it is the crankshaft is cast, but the rods are forged.

No mention of the piston construction method.

[e66man]

Ok so the rods and crank are forged ?
What about the pistons ???

There just isn't enough documentation publicly available yet. The most consistent thing I've read is that engine teardowns from pre-Dec '09 build date cars showed forged pistons with very few anomalies, which could have just been incorrect diagnoses. The rest were cast.

I would love to see the hard data if there is any out there though.

[Pyewacket69]

There just isn't enough documentation publicly available yet. The most consistent thing I've read is that engine teardowns from pre-Dec '09 build date cars showed forged pistons with very few anomalies, which could have just been incorrect diagnoses. The rest were cast.

I would love to see the hard data if there is any out there though.

If you're really chomping at the bit to get an answer, contact Bentley. I've asked questions via email to them before (then again, I own some of their manuals) and gotten quick responses.

I'm pretty sure they know the answers...