BANGING NOISE IN REAR SUSP. CAUSED BY R/SPRING CONTACT

VEHICLES AFFECTED: 1986 'H' MODELS

There have been some owner comments, on subject models, of a banging type rear suspension noise noticeable on rough roads. This noise can result from the rear spring upper coils contacting each other on compression. This condition was corrected on 1987 'H' models by new designed springs. To repair this condition replace the rear springs. To use the 1987 rear springs on a 1986 LeSabre, determine the code identification of the springs on the vehicle and obtain a 1987 service spring which has the same "Rate" and comes closest to the "Load" of these springs.

Figure 1 lists the "Rate" and "Load" of the 1986 front wheel drive LeSabres production springs. Figure 2 lists the currently released 1987 LeSabre service springs.

For example, if a 1986 vehicle has code MAS rear springs, the 1987 service springs, Code RRD, Part Number 25530346 should be ordered from GM Parts.

1986 DELTA 88

If the 1986 Delta 88 has optional F41 or FE3 suspension, replace the springs with the comparable 1987 replacement spring. Refer to the spring chart (Figure 3) for replacement spring application.

SUSPENSION Figure 1 - 1986 Front Wheel Drive LeSabre Production Rear Spring Usage

Rate Load N/mm N Part No Code ---- ---- ------- ---- Std Ride 42-60 3100 25525299 MAN -G67 42-60 3300 25525300 MAP 42-60 3500 25525301 MAR 42-60 3790 25525302 MAS 42-60 4020 25525303 MAT 42-60 4250 25525304 MAV 42-60 4480 25525305 MAW

F40/F41 45-60 3100 25525306 MAX -G67 45-60 3350 25525307 MAY 45-60 3600 25525308 MAZ 45-60 3850 25525309 MBA 45-60 4100 25525310 MBB 45-60 4350 25525311 MBC 4600 4600 25525686 MBD

Figure 2 - 1987 Front Wheel Drive LeSabre Service Rear Spring Chart

BASE 42-60 W/O G67 3464 25530344 RRB 3900 25530346 RRD 4336 25530348 RRH

F40/F41 45-60 W/O G67 3432 25530359 RRL 3900 25530361 RRN 4368 25530363 RRR

G67 = Automatic Level Control Option

DELTA 88 (H CAR) REAR SPRING CHART (Figure 3)

1986 Original Spring * 1987 Replacement Code Load Part No. * Code Load Part No.

Base Suspension 43.0 N/mm Rate

NYS 3480 10035259 * -------same------------ NYT 3720 10035260 * NYU 3960 25523979 * NYW 4200 25523980 * NYX 4440 25523982 *

-------------------------------------------------------- Base Suspension With G67 33.0 N/mm Rate

NTZ 3010 10027114 * -------same------------ NUA 3190 10027115 * NUB 3370 10027116 * NUC 3550 10027117 * NUD 3730 10027118 *

-------------------------------------------------------- F41 - FE3 Suspension 47.0 N/mm Rate

MBG 3260 25526961 * -------same------------ NZB 3520 25524840 * RRL 3432 25530359

NZC 3780 25524841 * RRN 3990 25530361 NZD 4040 25524842 * " " "

NZE 4300 25524843 * RRR 4368 25530363

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.