A new TSB on Engine "rattle" noise. Unverified.

[F9K9]

Scroll down or read all that was posted in S-10Forum

[HenryJ]

Same OLD fix that is no longer a recommended fix.

s-series forum thread

PS the quote you posted is technically incorrect. The shoe kit is installed under the dowel pins not over them.
Here's the actual GM bulletin.
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Subject: Rattle Noise in Engine (Install Timing Tensioner Kit) #03-06-01-024B - (03/04/2004)

Models: 1996-2003 Chevrolet Astro, Blazer, Express, S-10, Silverado
1996-2003 GMC Jimmy, Safari, Savana, Sierra, Sonoma
1996-2001 Oldsmobile Bravada
with 4.3L V6 Engine (VINs W, X -- RPOs L35, LU3)


This bulletin is being revised to change warranty information. Please discard Corporate Bulletin Number 03-06-01-024A (Section 06 -- Engine/Propulsion System).
Condition

Some customers may comment on a rattle-type noise coming from the engine at approximately 1800 to 2200 RPMs.
Cause

The spark, rattle-type noise may be caused by torsional vibration of the balance shaft.
Correction

If detonation noise is present , perform detonation/spark knock diagnostics first.

Install a new tensioner assembly kit using the procedure below.

1. Remove the engine front cover. Refer to SI for engine front cover removal procedure.
2. Remove the crankshaft sensor reluctor ring and line up the timing marks on the crank gear and cam shaft gear.
3. Remove the camshaft gear and chain. For model years 1996-1998, remove the crankshaft sprocket using J 5825-A.
4. Pull the shipping pin and discard. Remove the nylon timing chain tensioner blade from the timing chain tensioner bracket.
5. Position the bracket on the front of the engine. The upper two attaching holes of the bracket will line up with the center two engine front cover bolt holes. The lower bracket holes will line up with the engine front cover alignment holes.
6. Use a hammer and the J 46165 Pin Driver to install the dowel pins through the two lower holes in the bracket and into the engine block. Make sure that the bracket is held firmly in place before proceeding.
7. For model years 1996-1998, install a roller-type timing chain set. Install the crankshaft sprocket using the J 5590 Crankshaft Gear Installer.
8. Install the timing chain around the crankshaft sprocket and position the timing chain to the driver's side of the engine.
9. Install the nylon timing chain tensioner guide onto the timing chain tensioner bracket pin and position the top of the guide under the tab at the top of the bracket.
10. Install the camshaft sprocket into the chain and then to the camshaft. Install the bolts finger-tight. Make sure the timing marks are aligned, then tighten the camshaft sprocket bolt.

Tighten

Tighten the bolt to 25 N·m (18 lb ft).
11. Install the crankshaft reluctor ring.
12. Install the engine front cover and place a washer under the two center cover bolts that extend through the tensioner bracket. These washers are required to maintain the proper crush on the engine front cover seal.

Tighten

Tighten the bolts to 12 N·m (106 lb in).

Parts Information

Part Number Description Qty

12458911 Chain kit 1

89017257 Tensioner 1

10220906 Oil pan gasket 1

88893989 O ring and gasket kit 1

3754587 Water pump gasket 2

89017259 Cover 1

Parts are currently available from GMSPO.

[F9K9]

Didn't realize that the part dated

MAKE GM EFFECTIVE DATE 03/01/06
PART# GM89017257

was an old one.

[HenryJ]

I think that someone was confused somewhere. That part number was being confused as a dampner for the balanceshaft, when in fact it is the tensioner in the Timing Tensioner Kit.

It is tough to keep the "facts" straight on the internet.

[F9K9]

Hence........"A new TSB on Engine "rattle" noise. Unverified."

[HenryJ]

You did the right thing bringing it to light. I hope you didn't think that I thought you were confused. The person who found this "new" TSB must have been though.

The internet is like a huge circle of people sharing a story. The story can change, and things can get distorted. If the circle is large enough , when it returns to the source it may be seen as new or misconstrued as verification.

You know what they say " Believe only half of what you see and nothing that hear". Too bad you can only see the posts here

[F9K9]

I admit that I do not track down the origins of threads like this one (that would hold up under scrutiny in a court of law) but, the forum had a similar question (2500 rpm vibration) within an hr of me finding that particular thread. I was just tossing it out because I know there are "closet" GM techs lurking in the forums and was hoping that they or someone with the vibration problem would track down the validity of the unverified "tsb"