A/T - Delayed Transmission Engagement or No Drive
NO.: 21-20-93 Rev. AGROUP: Transmission
DATE: Oct. 22, 1993
SUBJECT:
Transmission Delayed Engagement or No Drive
NOTE:
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 21-20-93 ISSUED 7/23/93 WHICH SHOULD BE REMOVED FROM YOUR FILES. THE REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS**. ZJ LABOR TIME AND APPLICATION CORRECTED AND NOTES ADDED.
MODELS:
1988-1993 (B) (AB) Ram Van/Wagon
(D) (AD) Ram Pickup, Ram Cab & Chassis
(N) (AN) Dakota/Dakota Sport/Dakota Cab & Chassis
1993 (ZJ) Grand Cherokee
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH 42RH, 42RE, OR 46RH 4-SPEED AUTOMATIC TRANSMISSION.
SYMPTOM/CONDITION:
Some vehicles may exhibit a condition of "no drive" or "delayed transmission engagement". The customer may complain that the vehicle does not move after shifting from "Park" into "Drive" or "Reverse".
DIAGNOSIS:
The condition could be difficult for the owner to demonstrate. The cause is a rough finish on the sides of the park tooth on the overdrive annulus gear. It may only occur under certain combinations of grade, vehicle loading and which park tooth happens to be engaged.
The transmission actually engages, however, because the pawl has not released, no torque is transmitted to the drive shaft and the engagement is not felt. If the throttle is opened slightly, it may appear as if the transmission is in "Neutral". If the throttle is opened aggressively, the engine acts as if the transmission is in gear but the brakes are being applied.
Prior to any attempted repairs, all possible causes of "delayed engagement" or "no drive" should be checked.
Low oil level Shift Cable/Linkage Adjustment
Transmission Low Line Pressure Plugged Transmission Filter
Broken Pump Drive
PARTS REQUIRED:
REPAIR PROCEDURE:
This repair involves the removal of the overdrive unit and the replacement of the annulus gear.
1. Remove the overdrive unit as outlined in the appropriate service manual.
2. Disassemble the overdrive unit/overdrive gear train to the annulus gear as outlined in the service manual.
3. Install new annulus gear and assemble the overdrive gear train and overdrive unit.
**NOTE:
DETERMINE THE CORRECT THICKNESS OF THE OVERDRIVE PISTON THRUST PLATE. SEE SERVICE MANUAL FOR PROCEDURE.**
4. Install overdrive unit using a new gasket following the procedure outlined in the service manual.
5. Fill the transmission to the specified level with Mopar ATF PLUS, Type 7176 Transmission Fluid.
POLICY:
Reimbursable within the provisions of the warranty.
TIME ALLOWANCE: 2 WHEEL DRIVE MODELS
Labor Operation No. 21-20-21-90 B/AB, D/AD, A, N/AN 2.2 Hrs.
4 WHEEL DRIVE MODELS
Labor Operation No. 21-20-21-91 A/AW 4.1 Hrs.
N/AN, **ZJ** 3.7 Hrs.
FAILURE CODE: 58 - Internal Defect