Vinsanity

My crankshaft balancer pulley was wobbling and making noise on my '07 c6. So I started the journey to replace it with FSM and TSB 05-06-01-001A in hand.

I have the old pulley off and both the FSM & TSB tell me to "Place the old & new balancers on the bench and orient them the same way. Mark the new balancer in the same location as the old balancer." Well as you can see in mine, the weight holes on them are completely different. What does "in the same location" mean?

Also, I noticed that when I put them side by side, the new one is 1/8" deeper. The belt slots are the same size, but the new pulley will be spaced 1/8" farther from the engine block than the old. Should I be concerned?

Thanks!!

Mike's LS3

Does the silicone seal protrude more on the old HB? I suspect the outer ring has moved inward onto the hub (inner ring), thus causing a misalignment on the old HB..

irok

orient the spokes in the inner hub of the new balancer the same as the old balancer you removed if you have marked old balancer and location it was installed on crank snout.the hb is neutral balanced at factory and will not matter how many holes or weights it has in it.your balance installation will be fine

BlindSpot

Agree, it is the orientation on the crankshaft for both. The holes are a rotational balancing process done in manufacturing. You want the tight grouping of balance holes at the same degree from TDC new to old.

On the height, you're taking the wrong measurement. The measurement you're taking has no relationship to belt alignment. Set both units on a flatplate. Measure from the flatplate to the first tooth on the first serpentine pulley on both and compare. Then another measurement from the flatplate to the first tooth on the second serpentine pulley and compare. Bet they are the same.

Finally, you have such a golden opportunity that you're about to miss by replacing that HB with another GM unit. If you do, remember the process as you could be doing all of this over again next year, but at least you'll be good at it by then. Consider an aftermarket like Powerbond or ATI.

WW7

Why would you replace a junk balancer with another junk balancer.. Save yourself from having to replace the part again in a few years by getting an aftermarket balancer.. Do a search and you will see 100s of people on here have had to replace the balancers on these cars...Take the stock part back and get a Powerbond or an ATI.......WW

Dave S

Go with an ATI.....

CMY SIX

Power Bond SFI unit

Brandon619

Go with an aftermarket unit and be done.

Vinsanity

I threw out the packaging, so I can't return the OEM balancer. So going aftermarket would start by eating that. Maybe partially recoop it on ebay. The cheaper of ATI & Powerbond is the Powerbond PB1117SS for $220.

As some of you know, taking this apart was no quick task. I have no interest in repeating it. Realistically, what are the chances that the OEM one would fail again? I don't drive it easy but I don't take it to the track either. Is it really worth buying a second balancer?

Thanks!

BlindSpot

Just do a search on the C6 forum alone. You'll find numerous examples of 2nd and 3rd failures on the same car. A few within a year or less than the last install. Some get "caught" having to use the GM part BC a Chevy dealer is doing the work and won't warranty an aftermarket. At least one, I recall, got caught with the second failing right after the one year warranty expired.

I, for one, am not making recommendations NOT to install the GM part to be funny or as hyperbole. I make the recommendation based on the actual record.

NJ_phil

Just slap the new OEM balancer on and call it done.

Worse case it you'll only get 10-15 years out of it.

Use the money you save to take the wife out to dinner and keep the damn car parts off her granite countertops

WW7

This is terrible advice, sometimes it's better to "say nothing" if you don't know what your talking about.. My car is on it's third GM balancer because the previous owner had to have it replaced once under GM warranty, then again "8,000 miles later" under extended warranty..If I have to replace it again, it sure as hell won't be with a stock GM unit...The GM balancers are junk , it's a proven fact, so why spend the time and money to install GMs junk again..The OP needs to install an aftermarket balancer , then he can take the wife out to dinner....WW
.
.

HBsurfer

My stock balancer was shot at 25,000 miles. There are several people on here who have had them go bad in less than 10,000 miles.
Where do you get 10-15 years as a worst case?

irok

I've had new replacement GM hb's fail in as little as 4,000 miles.saw others that didn't make it home from dealership when car new with 35 miles on it

Vinsanity

Ok, I'm sold. There is a Powerbond SFI in my near future. Like I said, I really don't want to deal with this again.

Thanks guys!

HOXXOH

I have 140K miles on my OEM balancer that was removed and reinstalled at 72K with no concern for orientation. If I swap to an aftermarket unit, how and why would I need to set the 0 degree mark at TDC if there is no fixed pointer and I have no need to know the relationship? If both the factory unit and aftermarket's are independently balanced and there is no crankshaft keyway, why is orientation necessary?

Have the failures in A6 vs M6 cars been at a similar ratio as
production? I ask this, because the shock values on M6 cars greatly exceed the same of those with the A6. I've personally been above redline a minimum of 1000 times just at the dragstrip alone, so it appears that either high RPM alone is not a cause for failure or I've been extremely lucky.

HBsurfer

A6 here with no track time. Required replacement at 25,000 miles

WW7

I know some people who have never had problems with their stock balancers on there C6s.. I also know many who have had multiple failures like on my car.. I personally have never owned any other car where they had to replace the balancer because of it failing.. Balancers are usually a "very reliable" part and they almost never fail on any make/model of car..Anytime you see alot of posts over many years on a car site like this about balancer failure, you can be fairly sure there is a faulty part that's responsible...Yes, I would say your very lucky , so hold on to that balancer you have for sure.... I'm not sure if the A6 autos have the same failure rates as the M6s , but I agree with you that it would make sense that the manual trans cars have the ability to abuse the balancer more then the autos... .WW
.
.

BlindSpot

I didn't mean to imply the HB needs to be degreed in. I just worded that poorly in an attempt to help the OP understand a couple of steps in the TSB that I'm sure everyone just ignores.

GM has the installer on manuals placing an arbitrary reference mark on the old HB and the CS. Then on the bench, looking for weights added back in the holes on the old HB, and transferring those into the new HB and orienting those at the same position on the crank.

This suggests, that even though the rotating assembly is balanced, independently from the HB, that after final assembly, another measurement is taken and weights added back in. I agree, with an aftermarket HB this has to be ignored.

From GM:

Important:
• For manual transmission applications, note the
position of the crankshaft balancer before
removal;,The: balancer does not use a key or
keyway for positioning. Mark or scribe the end of
the crankshaft and the balancer before
component removal. The crankshaft balancer
51 must be'installed to the original position. If
replacing the^crankshaft balancer, riote the
location of any existing balance weights; if "
applicable. Crankshaft balance weights must be
installed into the new balancer in the same
location as the old balancer. A properly installed
balance weight will be either flush or below
flush with the face of the balancer.
• Do not use the crankshaft balancer bolt

irok

I believe the orientation is only for some to feel better about it.I've replaced approx. 12 of them and the majority of them were on auto cars.being neutral balanced means it wont matter where its installed.with 140,000 on your car you got a good one