Chrysler Full-Size Vans 1967-1988 Repair Guide

New Process A-903 3-Speed Overhaul


The A-903 is a 3-speed unit with helical type gears. It is fully synchronized in all gears. Lubricant capacity is 6 pints.


  1. Remove output shaft yoke.
  3. Remove case cover. Measure synchronizer float with a feeler gauge between the end of a synchronizer pin and the opposite synchronizer outer ring. A measurement from 0.050-0.090" is acceptable for 1967 models. The measurement should be 0.060-0.117" for 1968 and latermodels.
  5. Remove the extension housing from the case.
  7. Remove the main drive pinion bearing retainer.

Be careful to avoid binding the inner synchronizer ring on the drive pinion clutch teeth.

  1. When removing the drive pinion and bearing assembly from the pinion shaft. Remove the bearing washer, press the shaft out of the bearing and remove the oil slinger.
  3. Remove the mainshaft pilot bearing snapring from the cavity of the pinion gear.
  5. Remove the 14 pilot roller bearings.
  7. Place the transmission in reverse. Remove the outer center bearing snapring, then, partially remove the mainshaft.
  9. Remove clutch gear retaining snapring and clutch gear from the mainshaft.
  11. Slide the 2nd gear, stop ring and synchronizer spring off the mainshaft.
  13. Remove the low and reverse sliding gear and shift fork as the mainshaft is completely withdrawn from the case.
  15. Measure cluster gear end-play. End-play should be 0.005-0.22". This will determine what thrust washers are used at re-assembly.
  17. Remove the countershaft key and the countershaft.
  19. Lift the cluster gear and thrust washers from the case. Remove the 22 needle bearings from each end. Remove the spacer from the cluster.
  21. Remove the reverse idler shaft from the case. Remove the key.
  23. Remove the reverse idler gear, thrust washers and 22 needle bearings out of the case.
  25. Remove the gearshift operating levers.
  27. Drive out the tapered retaining pin from either of the two lever shafts and withdraw the shaft from the case. The detent balls are springloaded, so, as the shaft is being withdrawn, the balls will fall to the bottom of the case.
  29. Remove the interlock sleeve, spring pin and detent balls. Drive out the remaining tapered pin, then slide the lever shaft out of the transmission.
  31. Remove both lever shaft seals and discard same.


  1. Install two new shift lever seals in the case.
  3. Carefully insert the low and reverse lever shaft into the rear of the case, through the seal, and into position. Insert a tapered pin to lock it. Turn the lever until the center detent is in line with the interlock bore.
  5. Install the interlock sleeve in its bore in the case, an interlock ball, spring and pin.
  7. Place the remianing interlock ball on top of the interlock spring.
  9. Depress the interlock ball and, simultaneously, install the 2nd-3rd lever shaft into the fully seated position, with the center detent aligned with the detent ball. Secure the shaft with the remaining tapered pin.
  11. Install the operating levers and secure them to the shafts with nuts torqued to 18 ft. lbs.
  13. Slide the dummy shaft and tubular spacer into the bore of the countergear.
  15. Grease and install 22 bearing rollers into each end of the countergear bore in the area around the arbor. Install the bearing retaining rings at each end of the gear, covering the bearings.
  17. Install a thrust washer at each end of the countergear and over the arbor. Install the countergear assembly into the case, making sure that the tabs on the thrust washers slide into the grooves in the case. Correct cluster gear end-play is determined by the thrust washer thickness.
  19. Grease the reverse idler gear and slide the dummy shaft into the bore. Install 22 rollers in the bore and around the dummy shaft.
  21. Install a new thrust washer at each end of the gear and over the arbor.
  23. With the beveled end of the teeth forward, slide the gear into position in the case. Install the reverse idler shaft in its bore in the rear of the case. Install the key and align it with the keway in the case.
  25. Drive the shaft into the case and the idler gear until the key seats in the recess.
  27. Install the rear bearing on the mainshaft and install the selective fit snapring.
  29. Hold the 1st-Reverse sliding gear into position with the shift fork. Insert the mainshaft with rear bearing retainer through the rear of the case and into the sliding gear.
  31. Place the synchronizer spreader ring, and then the rear stop ring, on the synchronizer splines of the 2nd speed gear.
  33. Install the 2nd speed gear on the mainshaft, with shims, if required. Shims should be used to correct excessive synchronizer float. If synchronizer float is below minimum, as determined during disassembly, shorten all synchronizer pins.
  35. Install the synchronizer clutch gear and snapring on the mainshaft.
  37. Install the 2nd and 3rd fork in the lever shaft with the offset towards the rear of the transmission. Hold the synchronizer clutch gear sleeve and two outer rings together, with the pins in the holes in the clutch gear sleeve. Engage the 2nd-3rd fork with the clutch gear sleeve.
  39. While holding the synchronizer parts and fork in position, slide the mainshaft forward, starting the synchronizer clutch gear into the clutch gear sleeve and the mainshaft rear bearing into the case bore. The synchronizer parts must be correctly positioned before the mainshaft is positioned.
  41. While holding the synchronizer parts in position, tap the mainshaft forward until the rear bearing bottoms in the case bore.
  43. Install the mainshaft rear bearing selective fit snapring into the case bore groove.
  45. Slide the oil slinger over the pinion shaft against the gear.
  47. Slide the bearing over the pinion shaft with snapring groove away from gear, then seat bearing on shaft using an arbor press.
  49. Install the keyed washer and snapring. Four thicknesses of snapring are available to eliminate end-play. Install the large snapring onto the race of the ball bearing.
  51. Install the 14 greased bearing rollers into the bore of the pinion shaft gear. Install the bearing roller retaining ring in the pinion gear bore.
  53. Install the 3rd gear outer stop ring and 3rd gear inner stop ring onto the mainshaft. Guide the drive pinion through the front of the case and engage the inner stop ring with the clutch teeth, then, seat the bearing so the large snapring is flush against the case.
  55. Install a new bearing retainer seal and gasket.
  57. Install the retainer and torque it to 30 ft. lbs.
  59. Install a new rear mainshaft bushing and a new oil seal.
  61. Protect the oil seal with a thimble-type seal protector and, with the gasket attached, slide the extension housing against the case. Torque the bolts to 50 ft. lbs.
  63. Install the flange assembly and install a new washer and nut. Torque the nut to 140 ft. lbs.
  65. Grease the cover gasket and install the gasket on the cover. Install the cover and torque the bolts to 12 ft. lbs.
  67. Install the drain plug and back-up light switch.

Observe the following torques:

Back-up light switch-15 ft. lbs.
Drain plug-20 ft. lbs.
Filler plug-30 ft. lbs.
Case-to-clutch housing-50 ft. lbs.
Drive pinion bearing retainer-15 ft. lbs.
Extension hosuing-30 ft. lbs.
Gearshift fork lockbolt-30 ft. lbs.
Gearshift housing lower bolt-15 ft. lbs.
Gerrshift housing upper bolt-20 ft. lbs.
Gearshift operating lever nut-35 ft. lbs.
Gearshift rod and swivel nuts-70 in. lbs.
Gearshift selector ball spring bolt-25 ft. lbs.
Gearshift selector lever washer nut-20 ft. lbs.
Mainshaft flange nut-175 ft. lbs.
Gearshift lever shaft bolt-10 ft. lbs.
Operating lever nuts-18 ft. lbs.
Pinion bearing retainer bolt-30 ft. lbs.