a43656

While I'm here and semi-bored:
2008 HHR SS 5-speed, non-Brembo, but with Quaife LSD
Ownership began in 2015@107K miles - took ownership, car claimed to have new struts and new bearings at this time.
-Spark plugs
-Front swaybar bushings
-Airbox grommets
-Clutch/brake pedal pads
-New leather shift boot, greased shifter ball and rods/links, put in metal shifter bushing things (from some SAAB place?)
-Replaced trans fluid
-Clutch return spring and bushings

122K miles/2016:
-Replaced intermediate axle, CV/halfshafts, lower control arm bushings (all ACDelco)
-Lower control arm bushings (MOOG)
-Turned rotors, installed Akebono ceramic pads

130K miles/2016: Rear calipers (ACDelco)
134K miles/2017: Front hubs/bearings, new rear dampers (ACDelco)

150K/2018: Clutch replacement (LuK? OEM? Done by trans shop. Fixed clutch pedal return problem)

157K/2021: Preventive refresh: OEM struts, lower control arms, put on Brembos, replaced rattly urethane swaybar bushings with OEM, shifter rebuild and grease.

Current status: 162K miles, no problems, except what is presumed to be rattly chain and chain tensioner things that go away after 30 seconds? And a possible lash issue in the steering box if I don't have 100% perfect wheel balance. I have been reading on here about all things chain tensioner, chains, retainer bolt, etc.

Overall, this car has been amazing fun, supremely useful, very cheap and reliable to operate. I've essentially decided to keep it for a long time, and spend the time and money needed to continue maintaining it. I have dozens of photos of the car stuffed to the gills with firewood, 8' light fixtures, wire shelving, wheels and tires, etc.

a43656

Posing with Ecotec 2.0T cousin SAAB 9-3 "Sport Sedan" at Nelson Ledges Race Course ....

donbrew

Replace the timing chain NOW.
What is an intermediate axle?

a43656

Valve cover will come off ASAP for chain tensioner and bolt inspection, based on what I'm reading here.

Intermediate axle, meaning the straight one running parallel to the steering rack. It has been a long time, but if I'm remembering right, the transaxle is on the driver's side, and a straight axle/tube/bearing with pillow block goes from there to the right front CV. As a SAAB weirdo, I remembering seeing SAAB cast into the assembly. That bearing in the pillow block was failed, and made noises similar to a grinding/squealing brake.

Upon destructive inspection using a chopsaw cutoff wheel, mine had rusted internally, making the retainer ring from the inboard CV spline OD have no room to collapse inside the ID of the intermediate axle, so it was easier (and not very expensive) to just replace the intermediate axle and the CV/axle/halfshaft - otherwise, I believe I could have simply replaced the bearing. I remember having the intermediate axle and CV off the car ("fused" together from the rust and chocked up in a giant vise, torching it, trying to hammer it apart with an 8 or 10 lb solid rod of steel, and no luck at all.

Oldblue

X2 timing chain! No delays! Engine failure is way more expensive the timing chain and balance shaft chain.
Cloyes 9-4201SX and 9-4202SX for the 2.0 you don’t need the sprockets, just the guides, tensioners and chains
if you order from RockAuto don’t forget the discount code

a43656

Will do! Thanks!

donbrew

I never heard of anybody replacing or having trouble with that shaft. I had to look it up.
The MU3 trans is indeed a SAAB; one of the reasons GM bought SAAB then gutted it.

Oldblue

The axle shaft is longer on the right side , but no carrier bearing
https://www.rockauto.com/en/catalog/...n,cv+axle,2288

donbrew

I had to look it up; the MU3 has an interme4diate axle with a pillow bearing. It doesn't have a tail like the auto.

a43656

Hello all,

Semi-bored and extremely-boring update:

-We forgot to check anything regarding chain tension as we were taking it apart. Shame on us.
-Everything "looked perfect", including the "crappy bolt", and all the "Nylon" (?) guides. The presumably original 2008 OEM chain tensioner successfully compressed and rebounded under my thumb.. This could be meaningless anecdote, but it "looked fine". We replaced it nonetheless.
--We put in the one of the RockAuto-sourced Cloyes kits recommended above, by OldBlue, I think. Including replacing the "crappy bolt".
-What we believe to be original hoses still looked amazingly good.
-The serpentine belt, believed to be original 2008 with 162K miles, was missing large chunks. This is admirable as to belt performance, but not admirable for me as an HHR parent. It is a 3rd/4th car, go easy on me. Serpentine belt and tensioner were replaced, although with Federated parts in stock locally, not AC Delco OEM.
-We replaced the TTY (torque to yield) cam bolts.
-We gambled on reusing the TTY crank bolt, it wasn't available when we needed it to be. Public or private criticism is welcome.

Boring summary:
-Before doing all of this: 90+ seconds of disconcerting clattering on cold start - sewing machine quiet after that,
-After doing all of this: 45 seconds with 1/4 the clattering than before when cold - sewing machine smooth after that.ing l
Conclusion: Since the crappy bolt wasn't broken and nothing else "looked bad", maybe it was just a bit sloppy? Maybe it was all the tensioner?

I'm a decent former semi-pro mechanic but not an HHR/Cobalt/Ecotec expert, so I don't know what the remaining cold-temp clattering could be. Could be anything in the belt train. 99% sure it isn't trans/clutch/input shaft.throwout bearing. Overall, not that important.

Overall, I'm glad I did this to extend the life of what might be the best car I've ever owned, and thank you to everyone for their help, and extra thanks to OldBlue for some rapid-response in DMs about the importance of dealing with the "crappy bolt."

Any further advice or thoughts are welcome. This is a well-moderated forum of high quality advice, in my opinion,

Cheers!