Mystery "clunk" solved? ...kinda still need help

[GHEN]

So a few days ago I was driving and I heard a little "clunk" while shifting. Coming from the back, kinda faint but definitely there.

Decided maybe this was a sign to check the transmission fluid which I did (outlined in another thread).

While I was under the car I saw this:



So I tightened it with an Allen wrench, which is the only thing I have that would turn it.

The noise went away (which I attributed to the transmission fluid being drained and filled), and then today while driving I heard it again, this time quit distinctly from the right rear. I immediately thought of that errant bolt I had seen and sure enough after I jacked the car up tonight there is was sticking out again.

Here is a picture of the head:



So the questions are:

1. What is this bolt, and why does it keep backing out?
2. What driver do I need to properly turn/seat it?
3. Could this be responsible for the "clunking" noise while depressing the clutch pedal and or shifting?

Thanks everyone!

GHEN

[GHEN]

I THINK that is my CV joint, do I win anything?

GHEN

[RedBaron]

Yes, those are your CV Joints.

Those bolts are referred to as "Triple Square" or "Cheesehead" bolts. The 944 has three different sizes of them: 8mm (CV Joint bolts), 10mm (Camshaft sprocket bolts), and 12mm (Flywheel bolts.) I believe Lisle and Snap On both sell the different tools.

If those back out they could leave you stranded easily. You could just buy new bolts on pelican and change them all or you can take the CV's out and repack them with new grease and change the boots. Clarks has a guide on it: http://www.clarks-garage.com/shop-manual/susp-01.htm. Make sure to wear gloves!!

[Cocacolakidd]

That bolt/screw looks to be a 12 point internal, or Cheese Head Screw/Bolt. Use internal 12 point socket or Cheese head socket to tighten it.

To keep it tight find out what bolt it is, and the torque setting for it, clean all lubricants (Grease, Oil Sludge and dirt) from it to bare metal. That is the bolt itself complete and also the mating surface must be clean. Then and only then torque it down and it will have a much better chance of staying put.

[John_AZ]

New OEM bolts would be better-Pelican?

But for someone who uses a Kevlar cam belt...
Locking CV bolts
Ideola's Garage: Stage8 Fasteners for Porsches

GL
John

[Jrboulder]

Don't let it happen to you. I had to do a road side fix. when I got home I went to fastenall and bought some allen bolts in grade 12.9 and torqued those puppies down.

Jackson

[Cocacolakidd]

Stage "8" makes a set of locking bolts for our CV Joints - not to expensive.

Package #8324 (12) 8mm-1.25 x 50mm Locking CV Joint Bolts

World's Best Locking Fasteners & Locking Nuts and Bolts STAGE 8

[AKCJ]

I switched to the Stage8 bolts from Ideola and I'm glad I did. One less thing to worry about.

[GHEN]

Originally Posted by John_AZ

New OEM bolts would be better-Pelican?

But for someone who uses a Kevlar cam belt...
Locking CV bolts
Ideola's Garage: Stage8 Fasteners for Porsches

GL
John

Ha ha! Thanks John, I admit with some things I am a "belt and suspenders" type of guy.

I am going to clean and torque for now (actually already did it this morning); but I do believe I am going to go with the locking CV bolts when I take the car off the road for a week next Spring for some planned maintenance.

I appreciate all of the help and kindness everyone.


GHEN