CLIB0001

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Service Bulletin - Product
BACKED B Y
S U PP O RT
Powering Business Worldwide
Subject: Idle Rattle in Heavy-Duty Trucks
Document Number: CLIB0001
Updated: April 15, 2013
Date: October 18, 2005
Issue Description:
Idle rattle or neutral rattle is noise at idle caused by fluctuations in flywheel speed that
result in speed variations at the input shaft. This condition can cause the internal
gearing to con tact both the drive side and coast side, creating a continuous noise. Id le
rattle noise can be identified by slowly raising the engine RPM, usually between 700
and 1000 RPMs, until the noise is diminished or eliminated. Check with the engine
manufacturer for the recommended id le speed min/max settings. Idle rattle can also
be identified by depressing the clutch pedal to remove the free travel. This should
diminish or eliminate the noise at idle.
Idle rattle is not a component damaging condition , however it can be annoying to the
operator as it creates an abnormal noise.
Containment/Corrective Action:
Eaton has developed the VCT Plus PD (pre-damper) clutch disc that has a special first
stag e in the damper, which is designed to isolate the engine idle pulsations before the
pulsations reach the transmission. The pre-damper disc can be identified by the
presence of 7 small springs around the hub.
Possible options that can be implemented as a solution for field complaints:
•
Raising the engine idle RPM will change the idle characteristics of the engine and
the noise may diminish. Recommended maximum default idle speed is 750 RPM.
•
Install the VCT Plus PD (pre-damper) clutch discs, which are available for
applications up to 2250 lb-ft with the different Eaton 15.5" clutch models.
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Service Bulletin - Product
Affected Models/Population:
Heavy-Duty Trucks with Mechanical Transmissions and 15.5" clutches .
Field Strategy:
Idle rattle complaints are not the result of defective transmissions or the factoryinstalled master clutch . If an idle rattle compla int is encountered, the complaint may
be resolved by replacing the original clutch discs (front & rear) with the VCT Plus PD
discs only. There is no need to replace the intermediate plate or pressure plate, unless
damage or wear requires .
•
Implement the above corrective actions for problem resolution .
•
If the customer chooses to just replace the original clutch discs with the VCT Plus PD
discs, provide the following usage information .
-
Applications up to 1860 lb-ft - use disc part number 128716 (front & rear)
-
Applications from 1861 to 2050 lb-ft - use disc part number 128717 (front &
rear)
-
Applications from 2051 to 2250 lb-ft - use disc part number 128718 (front &
rear)
Damper Model
Clutch Descrietion
EP ADV 1552 1860'#
EP ADV 1552 2050'#
EP ADV 1552 1750#
EP ADV 1552 2250'#
SOLO ADV 1552 1860'#
SOLO ADV1552 2050'#
SOLO ADV 1552 1750#
SOLO ADV 1552 2250'#
VCTDlus
DOA#
VCTclusPD
DOA#
208925-20
208925-25
208925-24
208937-32
209701-20
209701-25
209701-24
209708-32
128708
128709
128707
128710
128708
128709
128707
128710
208925-30
208925-35
208925-34
208937-42
209701-30
209701-35
209701-34
209708-42
128716
128717
128715
128718
128716
128717
128715
128718
Channel
(Production
vs. Service)
BOTH
BOTH
BOTH
BOTH
BOTH
BOTH
BOTH
BOTH
Warranty Information:
Because idle rattle is not generated from , nor the result of, the clutch and its operation ,
Eaton will not approve or pay for the replacement of a clutch due to idle rattle
complaints.
Warranty Coverage:
None
The material contained in this bulletin is product improvement information. Eaton is not committed to, or liable
for, canvassing existing products.
FSUD: 2005-FSUD-604
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