WTB BMW???

WTB in this case meaning "What the berkeley???"

Aluminum engine mount bolts.

That is all.

BMW could have really used a good materials engineer during the 90's.

Knurled wrote: Aluminum engine mount bolts.

I know you're not, but I really wish you were kidding.

What chassis? I recall an aluminum "pin" thru a rubber bushing and an aluminum mount arm but never a threaded bolt.

the ones on my 318ti were very much made of steel

Knurled wrote: WTB in this case meaning "What the berkeley???" Aluminum engine mount bolts. That is all.

Sure they're not super awesome titanium?

Titanium block, so they need aluminum fasteners to avoid electrolysis.

One time use, which is good since at least a few of the aluminum valve cover bolts are broken when I go to remove them most of the time.

titanium block?

I certainly hope that an E90 328 doesn't have a titanium block...

Searching for "broken BMW motor mount bolt" on Google gets many, many, many hits.

mad_machine wrote: titanium block?

oops, let me retract that. Magnesium block actually

that sounds more likely.. titanium would get expensive in a hurry

I didn't do the repair, but co-worker confirms that the block was possibly magnesium. I didn't saw off a chunk and light it to find out

The odd thing is, Audi used magnesium valve covers for years, with steel hardware. I guess BMW isn't up on Audi's fantastic fastener technology. And then there's all the Porsches with magnesium lug nuts.

Now, if the thing DOES have a magnesium block, then why does that 3-series feel like it weighs as much as a Suburban?

E90's had a Mag and aluminum block. My coworker just had one of the motor mount bolts fail too. Something like $500 to fix at the dealer he said. I would have fixed it for half :)

Depends on what breaks. On this one nothing broke but the bolts and the CV boot band since the exhaust pipes were holding the engine up, but the right inner boot was juuust grazing the subframe. It was close enough to break the clamp but not enough to tear the boot.

While researching, I found that it's not uncommon for other models to break the radiator, fan, coolant reservoir, water pump... all SORTS of money goes flying out of your wallet when that happens.

BMW dealership had tons of the bolts in stock, so that's what went back in. If BMW did something so on-the-surface dumb like using four aluminum M10 bolts to hold the engine mount on, they had to have had a very good reason. (But srsly, if they HAVE to be Al, why not M12 or M14?) Torque spec, as I recall, was 28ft-lb.