Stiffening plate removal / reinstallation

[StephenVA]

I stand corrected for all the reasons you mentioned.

[wpoll]

Originally Posted by oldskewel

.... Besides, unless you have one of the 1% of x5's without a perpetually oil-coated stiffening plate, you don't need to worry about corrosion.

Oh no - there must have something wrong with my X5 - there's supposed to be oil on the stiffening plate? What grade should I put on there and how much?

[bcredliner]

I have removed and installed the stiffing plate many times, always by myself. I have not had to use any special tools. I always replace both the nuts and bolts. As you mention there are many schools of thought, my default position is always to do as recommended by BMW in cases such as this.

[luvmy03E53]

Originally Posted by wpoll

Oh no - there must have something wrong with my X5 - there's supposed to be oil on the stiffening plate? What grade should I put on there and how much?

I think the consensus for the 3.0L M54B30 is Shell Rotella T6, 5W40, probably about a pint or so...

[StephenVA]

Crap...Now I have to go and buy another oil......

[luvmy03E53]

Originally Posted by StephenVA

Crap...Now I have to go and buy another oil......

No worries, Stephen... I hear the V8's use Louisville Cardinal tears as lubricant in lieu of oil... quite an abundance of that today...

[StephenVA]

No no no. Oil leaks and Coolant leaks on V8 are not leaking some thing like fluids as they are really leaking $$$$.

But then the 3.0 leaking at the Oil filter housing are leaking labor through that $9.88 gasket....

[jjmead1]

If you would be so kind as to follow up on this after doing the work that would be greatly appreciated. I have a leak from the front of the stiffening plate as well. I wanted to remove the plate and have a look but the bolt issue has prevented me from simply taking an exploratory looksee. The X is my only driver right now and I must complete the task in one sitting as it were. Thanks.

[Scott ZHP]

Originally Posted by oldskewel

Grade 8 is not the same as (8.8). Grade 8 is used for rating SAE bolts. The equivalent rating for Metric would be Class 10.9. "Class" for Metric, "Grade" for SAE. Class 10.9 is what these BMW overpriced bolts are rated at. Grade 5 SAE bolts are similar in strength to Class 8.8. Grade 8 SAE ~ Class 10.9.

I would just stick with M10 10.9 bolts. And make sure you get the right thread pitch too, since that affects the actual bolt stretch that occurs when you torque or TTY them down.

Stainless - no, don't do that. Stainless will be weaker, and it seems clear BMW was concerned with a specific strength rating here. If it says 10.9 on the bolt, it will be what you want. If it does not, keep looking. Besides, unless you have one of the 1% of x5's without a perpetually oil-coated stiffening plate, you don't need to worry about corrosion.

Good summary!

My go-to reference for hardware is Carroll Smith's "Nuts, Bolts, Fasteners and Plumbing" ... https://www.amazon.com/Fasteners-Plu.../dp/0879384069

It's a superb reference book.

[cn90]

I did the fluid maintenance a few years ago. I re-used the bolts.
Not sure why BMW said it is TTY bolt.
When looking at the bolts, they are big like wheel lugs and they looked just fine w/o any stretch marks typically seen in TTY bolts (such as head gasket bolts).

BTW, there are some repair manuals (on certain car models) that say replace the wheel lugs when changing tire. I just laugh at it.

Just relax, Saturday mechanics don't fix car for a living, so they follow the Bible to the "t". BMW mechanics tell me they re-use the bolts.

I posted the DIY below. The key thing is "relax", don't lose sleep over this TTY thingy, it is an overkill when it comes to these 6 bolts:

http://www.xoutpost.com/bmw-sav-foru...se-fluids.html