Harsh 1-2 Upshift, SES, MIL, or CEL Illuminated, DTC P1870 Set (Replace Valve Body)
| Subject: | Harsh 1-2 Upshift, SES, MIL, or CEL Illuminated, DTC P1870 Set (Replace Valve Body) |
| Models: | 1996 Buick Roadmaster |
| 1996 Cadillac Fleetwood |
| 1999-2000 Cadillac Escalade |
| 1996-2000 Chevrolet Camaro, Corvette |
| 1996-2000 Pontiac Firebird |
| 1996-2000 Chevrolet and GMC Light Duty Truck Models |
| 1996-2000 Oldsmobile Bravada |
| with 4L60-E Automatic Transmission (RPO M30) |
| Built Prior to January 15, 2000 (Julian Date 0015) |
This bulletin is being revised to update VIN Breakpoint Date information and revise the Parts Information table. Please discard Corporate Bulletin Number 01-07-30-023A (Section 07 -- Transmission/Transaxle).
Condition
Some customers may comment on a harsh 1-2 upshift and the Check Engine Light or Service Engine Soon indicator is illuminated.
Diagnosis
Typically, these vehicles will have been driven more than 32,000 km (20,000 mi) before this condition occurs.
The scan tool may show a DTC P1870 set as a history code.
A harsh 1-2 shift or DTC P1870, caused by wear in the control valve body, may be difficult to duplicate when the transmission temperature is below 93°C (200°F).
Cause
The condition may be due to wear in the control valve body. This wear occurs in the bore that contains the TCC isolator and regulator valves, and results in poor, or no, TCC apply.
Important:
• DTC P1870 is a type B code. The conditions for setting
the P1870 DTC must occur on TWO CONSECUTIVE TRIPS (ignition cycles, with
a drive cycle) before setting a P1870 history code. • When the conditions for setting DTC P1870 are met (first trip),
the PCM commands maximum line pressure and harsh 1-2 shifts are the
result. • This may result in a harsh 1-2 shift with no history code if the
conditions for setting the DTC required for the second trip are not met,
on two consecutive trips (Ignition cycles, with a drive cycle). • When the conditions for setting the DTC are met, on the second consecutive
trip, a DTC P1870 is stored as a history code. • When the P1870 code is stored, the PCM will turn on the Service Engine
Soon (SES), Check Engine Light (CEL), or Malfunction Indicator Lamp (MIL).
Correction
Install a control valve body with the revised TCC regulator and isolator valves. Refer to the Parts Information table below. These valves are used in all transmissions produced after January 15, 2000 (Julian Date 0015), and all of the service parts currently available through GMSPO contain revised TCC regulator and isolator valves.
Important: If all of the following conditions are true, it is not necessary to
rebuild the transmission or to replace additional transmission components
beyond the control valve body.
• Transmission operation is normal before the transmission reaches operating
temperature, or before DTC P1870 is set (no slips, flares, or missing
gears). • The torque converter is not blue or overheated. • The transmission fluid is not burned or has no burned odor. • The transmission fluid pan contains no abnormal debris (clutch material,
bronze, brass, or metal fragments).
Parts Information
Model Year | Vehicle Platform | Engine (RPO) | Transmission (RPO) | Transmission Broadcast Code | P/N |
|---|---|---|---|---|---|
1996 | S Truck | 2.2L (LN2) | 4L60-E (M30) | SAD | 24217855 |
1996 | C Truck (Mexico) | 5.7L (LO5) | 4L60-E (M30) | CPD | 24217856 |
1996 | C/K Truck G Van | 5.0L (L30) | 4L60-E (M30) | CCD, CFD, KBD, WAD, WBD | 24217856 |
1996 | C/K Truck G Van | 5.7L (L31) | 4L60-E (M30) | CHD, CJD, KCD, CMD, CUD, KPD, YDD, FFD, WCD, WHD | 24217857 |
1996 | F Car Y Car | 5.7L (LT1) | 4L60-E (M30) | FFD, YDD | 24217857 |
1996 | D Car | 5.7L (L31) | 4L60-E (M30) | AHD | 24217857 |
1996 | S/T Truck M/L Van | 4.3L (L35) | 4L60-E (M30) | TBD,TAD, MSD, MDD | 24217860 |
1996 | C/K Truck G Van | 4.3L (L35) | 4L60-E (M30) | CAD, CBD, KAD | 24217861 |
1996 | S/T Truck | 4.3L (LF6) | 4L60-E (M30) | SHD, TLD | 24217862 |
1996 | B Car | 4.3L (L99) | 4L60-E (M30) | BBD, BCD | 24217863 |
1996 | B Car (Includes Police Pkg.) | 5.7L (LT1) | 4L60-E (M30) | BFD, BWD, BKD | 24217864 |
1996 | F Car | 3.8L (L36) | 4L60-E (M30) | FCD, FBD | 24217865 |
1997 | S Truck | 2.2L (LN2) | 4L60-E (M30) | SAD | 24217866 |
1997 | C/K Truck G Van | 4.3L (L35) | 4L60-E (M30) | CAD, CBD, KAD | 24217867 |
1997 | S/T Truck M/L Van | 4.3L (L35) 4.3L (LF6) | 4L60-E (M30) | SHD, TLD, TBD, TAD, MSD, MDD | 24217868 |
1997 | C Truck (Mexico) | 5.7L (L31) | 4L60-E (M30) | CPD | 24217869 |
1997 | C/K Truck G Van | 5.0L (L30) | 4L60-E (M30) | CCD, CFD, KBD | 24217869 |
1997 | C/K Truck G Van | 5.7L (L31) | 4L60-E (M30) | CJD, CHD, KCD | 24217870 |
1997 | F Car Y Car | 5.7L (LS1) | 4L60-E (M30) | FFD, YDD | 24217870 |
1997 | F Car | 3.8L (L36) | 4L60-E (M30) | CFD, FBD | 24217871 |
1998 | C/K Truck G Van | 5.7L (L31) 5.0L (L30) | 4L60-E (M30) | ADD, AFD, AJD, ALD, AWD, CCD, CFD, KBD, CHD, CJD, KCD | 24221155 |
1998-2000 | C/K Truck G Van S/T Truck M/L Van | 4.3L (L35) 4.3L (LF6) | 4L60-E (M30) | TAD, MSD, CAD, CBD, KAD, WBD, SHD | 24221154 |
1998-2000 | S Truck | 2.2L (LN2) 2.2L (L43) | 4L60-E (M30) | SAD | 24221153 |
1998-2000 | F Car | 3.8L (L36) | 4L60-E (M30) | FBD, FCD | 24221159 |
1998-2000 | F Car Y Car | 5.7L (LS1) | 4L60-E (M30) | FFD, YDD | 24221158 |
1998-2000 | C/K Truck (Includes Police Pkg.) G Van | 5.7L (L31) 5.0L (L30) | 4L60-E (M30) | LHD, LSD, LUD, LPD, KXD, CPD | 24221161 |
1999-2000 | C/K Truck | 4.8L (LR4) | 4L60-E (M30) | CCD, CFD, KBD | 24221162 |
1999-2000 | C/K Truck | 5.3L (LM7) | 4L60-E (M30) | CJD, CHD, KCD | 24221162 |
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
K6560 | Valve Body - R&R or Replace | Use Published Labor Operation Time |
