Engine Gaskets, Seals, and TTY Bolts

Mayor West

Goblin Guru
I'm doing a general overhaul/cleaning of most of the engine's seals/gaskets/etc to keep myself busy while I save up for the kid components, the head's off and I'm deep cleaning everything. I need a lot of gaskets/seals.

I have a few questions:
  • Which bolts are TTY?
    • I've seen head bolts and flywheel bolts but I'm not 100% certain those are it or which cam bolts are TTY.
  • Where's the best place to get all the gaskets and seals?
    • I've found a lot of them on ZZP but not everything.
    • Hoping GM is a last resort...
  • What's the best quality, but not super high-priced timing chain set?
    • ZZP is about $300 and I'd prefer to spend a lot less than that if I can help it.
  • The orientation of the two balance shafts, is there info on that?
    • When I removed them I wasn't thinking about re-installation...
I should probably get a shop manual but they're also $300.

I'm not planning on doing any engine modifications aside from a tune, so I'm not building anything up while I'm in there to save money.

Mayor West

Goblin Guru
Here's a list of all the engine gaskets/seals I've found, as well as their GM part numbers.

These are for an '09 SS

Some part look ups said these did not fit my car but no substitute was found, so your mileage may vary and do your own research.
Some parts are cheaper if sold in kits, but again, take it for what it is.

I looked through the following sites:
ZZP had only a few of these substantially cheaper than GM. For the most part ZZP was about 2-3x the cost of GM directly. Water Pump was the main cost difference favoring ZZP, but they're sold out right now.
  • 12591866 Rear Main Seal
  • 12584041 Front Main Seal
  • 11570626 Flywheel Bolts (TTY) x8
  • 24435052 Timing Cover Gasket
  • 12609291 Valve Cover Gasket
  • 12589346 Head Gasket
  • 12589416 Throttle Body Gasket
  • 12589366 Intake Manifold Gasket
  • 12622668 Exhaust Manifold Gasket
  • 12595951 Fuel Pump Gasket
  • 12653395 Injector O-Rings Kit
  • 90537691 Head Bolt (Black) (TTY) x10
  • 24407225 Head Bolt (Grey) (TTY) x4
  • 12589461 Head Fuel Pump Side Gasket
  • 12618586 Turbo Exhaust Gasket
  • 12605720 PCV Seal
  • 12626102 Coolant Return Gasket x4
  • 12611119 Oil Return Gasket x2
  • 12589435 Oil return Hose Gasket
  • 12612817 Oil Return Seal
  • 12612816 Oil Return Seal
  • 12601372 Oil Cooler Seal (Sm)
  • 12601371 Oil Cooler Seal (Lg)
  • 12630084 Water Pump - Entire Assembly
  • 24446365 Water Pump mid-housing gasket - Included in Water Pump
  • 24439799 Water Pump Seal - Included in Water Pump
  • 90537915 Front Cover Water Pump Access
  • 90537379 Water Pump Outlet Pipe Seals x2
  • 3522676 Thermostat Seal
  • 90537471 Thermostat Housing
  • 12622410 Thermostat


Goblin Guru
Go with the Cloyes timing chain set. There are really good videos from Cloyes in how to install it properly and set up the proper timing. There are other discussions on this forum about them if you search for Cloyes.

I’m not a huge fan of ZZP, many of their items are overpriced. If you do your research, you can get things elsewhere. They are good for all things performance.

Mayor West

Goblin Guru
Right, I guess I'm just referencing them because they're the main search result when I google Cobalt parts. I definitely won't be using them for OEM seals and gaskets. Looking through Rock Auto now, will update if I find any good results.

Regarding the Timing Kit, I've looked at Cloyes videos and such and have them saved for review later on.