CTS V8-5.7L VIN P (2004)
Rear Subframe Mount: Technical Service Bulletins
Drivetrain - Rear Wheel Hop Control
Bulletin No.: 05-04-114-001B
Date: January 23, 2008
TECHNICAL
Subject:
Controlling Rear Axle or Wheel Hop on Full-Throttle Application From a Standstill and/or Full-Throttle 1-2 Shift (Install Supplementary Rear
Sub-Frame Bushings)
Models:
2004-2005 Cadillac CTS-V
Attention:
The information presented in this bulletin is intended to inform educate and provide an effective means to further improve the outstanding
high-performance handling qualities of the CTS-V for customers who value very aggressive driving capabilities.
Supercede:
This bulletin is being revised to revise the Warranty Information Section. Please discard Corporate Bulletin Number 05-04-114-001A (Section 04 -
Driveline/Axle).
Condition
Some customers may comment on rear wheel hop or rear suspension bounce under full throttle acceleration. This condition is not unsafe by itself and is
the result of very aggressive driving practices. This condition is primarily confined to hard acceleration from a standstill with wide open throttle though it
may be possible to induce if the customer attempts a hurried wide open throttle or "Power-Shift" from 1st to 2nd gear.
Vehicle component durability is greatly influenced by these driver abuses. Driving in this manner is not recommended.
Customer Expectations and Real World Usage
The CTS-V is a very high performance vehicle capable of class-leading acceleration that, in most cases, exceeds even the capabilities of pure sport and
muscle cars. The 5.7L V8 engine in the CTS-V provides outstanding reserves of power. This large available engine torque, coupled with a suspension
system and tire combination designed for maximum road adhesion, may result in wheel hop under certain conditions.
Cause
In the rear of the CTS-V, a sub-frame is mounted to the body structure at four rubber-isolated points. These mounts were carefully chosen to achieve an
effective combination of excellent handling, while retaining effective damping of road shocks and bumps. The force of the suspension rapidly occillating
vertically (hopping) provides enough weight transfer (up and down) that these bushings, which normally compress to help isolate passengers from
irregular road surfaces, may deflect or compress in sympathy to wheel hop.
Correction
Improving High Performance Suspension Characteristics
For customers who value very aggressive driving capabilities, a revised set of firmer rear sub-frame bushings are available that may provide an
incremental improvement in reducing the tendency of the rear suspension to wheel hop. This is an improvement that will further extend the handling
capabilities of the CTS-V - it will not remove the possibility of wheel hop in all situations.
Do NOT replace the rear sub-frame bushings unless the customer specifically has the concern of objectionable wheel hop.
Service Procedure
Use the following procedure to install the service rear frame supplemental bushings.
Raise and suitably support the vehicle.
Remove the left and right rear tire assemblies.
Support the right rear lower control arm with a stand.