SERVICE MANUAL UPDATE - SEC. 7 TRANS. UNIT REPAIR INFORMATION
SUBJECT: 1992 BROUGHAM SERVICE INFORMATION MANUAL TRANSMISSION UNIT REPAIR UPDATE ON 1992 BROUGHAMS WITH HYDRA-MATIC 4L60 (RPO MD8) TRANSMISSION
This bulletin provides new product information for the 1992 Brougham Hydra-Matic 4L60 (RPO MD8) transmission. This information is more recent and the attached pages should be used to update Section 4L60 of the 1991-1992 Brougham Service Information Manual. These attached pages include:
o An updated control valve assembly diagram (page 4L60-50).
o An updated second apply piston and housing application chart (page 4L60-56).
On August 14, 1991 (Julian Date 226) the TV limit line up changed on the Hydra-Matic 4L60 transmissions. The changes included a new TV limit valve (332), a new TV limit valve spring (331), and eliminates the TV limit plug (351).
Be certain to familiarize yourself with these updates to properly repair the 1992 Hydra-Matic 4L60 transmission.
**PLEASE REFER TO FIGURE 112 CONTROL VALVE ASSEMBLY** ----------------------------------------------------- 301 VALVE, T.V. MODULATOR DOWNSHIFT 302 SPRING, T.V. MODULATOR DOWNSHIFT VALVE 303 VALVE, T.V. MODULATOR UPSHIFT 304 SPRING, T.V. MODULATOR UPSHIFT VALVE 309 SLEEVE, 3-4 THROTTLE VALVE 310 SPRING, 3-4 THROTTLE VALVE 311 VALVE, 3-4 THROTTLE 312 VALVE, 3-4 SHIFT 313 SLEEVE, 2-3 THROTTLE VALVE 314 SPRING, 2-3 THROTTLE VALVE 315 VALVE, 2-3 THROTTLE 316 VALVE, 2-3 SHIFT 317 SLEEVE, 1-2 THROTTLE VALVE 318 SPRING, 1-2 THROTTLE VALVE 319 VALVE, 1-2 THROTTLE 322 VALVE, 1-2 SHIFT 323 SLEEVE, THROTTLE VALVE PLUNGER 324 PLUNGER, THROTTLE VALVE 325 SPRING, THROTTLE VALVE 326 VALVE, THROTTLE 328 VALVE, 3-4 RELAY 329 VALVE, 4-3 SEQUENCE 330 SPRING, 4-3 SEQUENCE VALVE 331 SPRING, T.V. LIMIT VALVE 332 VALVE, T.V. LIMIT 333 VALVE, 1-2 ACCUMULATOR 334 SLEEVE, 1-2 ACCUMULATOR VALVE 335 SPRING, 1-2 ACCUMULATOR VALVE 336 VALVE, LINE BIAS 337 SPRING, LINE BIAS VALVE 338 SPRING, 3-2 CONTROL 339 VALVE, 3-2 CONTROL 340 VALVE, MANUAL 341 PIN, COILED SPRING 342 PIN, COILED SPRING 343 RETAINER, SPRING (SLEEVE) 344 PLUG, VALVE BORE 345 PLUG, CUP (.33 DIA) 346 SWITCH ASM., PRESSURE (3RD CL.) 347 SWITCH ASM., PRESSURE (4-3 PULSE) 348 SWITCH ASM., PRESSURE (4TH CL.) 349 SWITCH ASM., PRESSURE (T.C.C. SIGNAL) 350 BODY, CONTROL VALVE 351 PLUG, T.V. LIMIT 352 PLUG, VALVE BORE (12.5 - O.D.)
o Cover (15) for porosity or damage.
o Seals for:
- Nicks or cuts.
- Freeness in the seal groove.
o Springs for distortion.
o Pin for wear or burrs.
IMPORTANT
o Check servo bore in the case for any wear which may cut the servo seals.
MEASURE
Figure 121
1. Measure piston (25) dimension *A.
2. Measure housing (22) dimension **B.
3. Check model application.
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.
