Chrysler Full-Size Trucks 1989-1996 Repair Guide

Crankshaft and Main Bearings

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REMOVAL & INSTALLATION



Gasoline Engines
ENGINE IN THE VEHICLE

For V6, V8 and V10 engines, you will need a Crankshaft Main Bearing Remover/Installer Tool C-3059, or equivalent, to service the upper main bearing halves.

  1. Remove the oil pan and gasket. For V6 and V8 engines, remove the oil pump. For V10 engines, remove the oil pump pick-up tube.
  2.  

No crankshaft bearing parts are interchangeable. All parts, if being reused, should be marked or organized so as to allow reassembly in the exact same order as when removed. If the crankshaft is being replaced, all bearings (main and connecting rod bearings) should be replaced with new parts.

  1. Make sure all bearing caps (main and connecting rod) are marked so that they can be installed in their original locations. Turn the crankshaft until the connecting rod from which the cap is being removed is down, and remove the bearing cap. Push the connecting rod and piston assembly up into the cylinder. Repeat this procedure until all the connecting rod bearing caps are removed.
  2.  
  3. Remove the main bearings caps.
  4.  


WARNING
Be careful not to nick the crankshaft journals. For V10 engine, DO NOT remove the black coating on the skirt. This is a factory applied dry lubricant.

  1. Carefully lift the crankshaft out of the block so that the thrust bearing surfaces are not damaged. Handle the crankshaft with care to avoid possible fracture to the finished surfaces.
  2.  
  3. Remove the rear journal seal from the block and rear main bearing cap.
  4.  
  5. Remove the main bearing inserts from the block and bearing caps.
  6.  
  7. Remove the connecting rod bearing inserts from the connecting rods and caps.
  8.  

To install:
  1. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings. Be sure the bearing inserts and bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.
  2.  
  3. Place the upper main bearing inserts in position in the bores with the tang fitting in the slot. Be sure the oil holes in the bearing inserts are aligned with the oil holes in the cylinder block.
  4.  
  5. Install the lower main bearing inserts in the bearing caps.
  6.  

Refer to the torque specifications chart for the torque figures for your particular engine.

  1. Clean the rear journal oil seal groove and the mating surfaces of the block and rear main bearing cap.
  2.  
  3. Dip the lip-type seal halves in clean engine oil. Install the seals in the bearing cap and block with the undercut side of the seal toward the front of the engine.
  4.  

This procedure applies only to engines with two piece rear main bearing oil seals. Those having one piece seals will be installed after the crankshaft is in place.

  1. Carefully install the crankshaft into place. Be careful not to damage the bearing surfaces.
  2.  

ENGINE OUT OF THE VEHICLE

See Figures 1 and 2

No crankshaft bearing parts are interchangeable. All parts, if being reused, should be marked or organized so as to allow reassembly in the exact same order as when removed. If the crankshaft is being replaced, all bearings (main and connecting rod bearings) should be replaced with new parts.

  1. With the engine removed from the vehicle and placed in a workstand, disconnect the spark plug wires from the spark plugs and remove the wires and bracket assembly from the attaching stud on the valve cylinder head cover(s) if so equipped. Disconnect the coil to distributor high tension lead at the coil. Remove the distributor cap and spark plug wires as an assembly. Remove the spark plugs to allow easy rotation of the crankshaft.
  2.  

For V6, V8 and V10 engines, you will need a Crankshaft Main Bearing Remover/Installer Tool C-3059, or equivalent, to service the upper main bearing halves.

  1. Remove the fuel pump and oil filter. Slide the water pump by-pass hose clamp (if so equipped) toward the water pump. Remove the alternator and mounting brackets.
  2.  
  3. Remove the crankshaft pulley from the crankshaft vibration damper. Remove the capscrew and washer from the end of the crankshaft. Install a universal puller on the crankshaft vibration damper and remove the damper.
  4.  
  5. Remove the cylinder front cover and crankshaft gear, refer to the earlier procedure on removing the front cover, in this section.
  6.  



Click image to see an enlarged view

Fig. Fig. 1: Exploded view of the crankshaft and intermediate shaft assembly-2.5L engine

  1. Invert the engine on the workstand. Remove the clutch pressure plate and disc (manual shift transmission). Remove the flywheel and engine rear cover plate. Remove the oil pan and gasket. Remove the oil pump.
  2.  
  3. Make sure all bearing caps (main and connecting rod) are marked so that they can be installed in their original locations. Turn the crankshaft until the connecting rod from which the cap is being removed is down, and remove the bearing cap. Push the connecting rod and piston assembly up into the cylinder. Repeat this procedure until all the connecting rod bearing caps are removed.
  4.  
  5. Remove the main bearings caps.
  6.  
  7. Carefully lift the crankshaft out of the block so that the thrust bearing surfaces are not damaged. Handle the crankshaft with care to avoid possible fracture to the finished surfaces.
  8.  
  9. Remove the rear journal seal from the block and rear main bearing cap.
  10.  
  11. Remove the main bearing inserts from the block and bearing caps.
  12.  
  13. Remove the connecting rod bearing inserts from the connecting rods and caps.
  14.  

To install:
  1. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings. Be sure the bearing inserts and bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.
  2.  


WARNING
Be careful not to nick the crankshaft journals. For V10 engine, DO NOT remove the black coating on the skirt. This is a factory applied dry lubricant.

Click image to see an enlarged view

Fig. Fig. 2: Exploded view of the crankshaft and main bearing assembly-V10 engine


  1. Place the upper main bearing inserts in position in the bores with the tang fitting in the slot. Be sure the oil holes in the bearing inserts are aligned with the oil holes in the cylinder block.
  2.  
  3. Install the lower main bearing inserts in the bearing caps.
  4.  

Refer to the torque specifications chart for the torque figures for your particular engine.

  1. Clean the rear journal oil seal groove and the mating surfaces of the block and rear main bearing cap.
  2.  
  3. Dip the lip-type seal halves in clean engine oil. Install the seals in the bearing cap and block with the undercut side of the seal toward the front of the engine.
  4.  

This procedure applies only to engines with two piece rear main bearing oil seals. Those having one piece seals will be installed after the crankshaft is in place.

  1. Carefully lower the crankshaft into place. Be careful not to damage the bearing surfaces.
  2.  

Diesel Engines

  1. With the engine secured on a workstand, with the cylinder head unfastened and placed aside, start by removing the top ridge from cylinder sleeve with a Ridge Reamer, tool C-3012, or equivalent.
  2.  

Keep tops of pistons covered during this procedure.

  1. As each piston and rod assembly is pushed out of bore, match the cap and rod assemblies. Also, identify the pistons and rods by cylinder.
  2.  
  3. Rotate the crankshaft to center each one of the connecting rods in the bore. Remove cap.
  4.  
  5. Turn the block sideways to remove the pistons and rod assemblies through the top of the block. Use bolt covers to protect journal surfaces. Push on upper bearing inserts with a hardwood blocks to remove assemblies.
  6.  
  7. Remove the main bearing caps from Nos. 1 and 7 bearings using puller C-3752-D (or its equivalent) and adapters. Remove the lower bearing inserts. Make sure to mark them as to cap number.
  8.  
  9. Remove the caps from Nos. 2 through 6 main bearings using the puller and adapters. Remove the lower bearing inserts. Make sure to mark them as to cap number.
  10.  
  11. Lift out the crankshaft.
  12.  
  13. Remove the upper bearing inserts. Identify the upper main bearings inserts, mate with corresponding lower main bearing inserts. Identify bearing pairs as to cap number.
  14.  
  15. Remove the thrust plates from No. 7 main bearing journal.
  16.  

CLEANING AND INSPECTION



Crankshaft

See Figures 1 and 2

Handle the crankshaft carefully to avoid damage to the finish surfaces. V10 engine crankshafts are specially coated with a dark, dry lubricant. This should not be removed.

  1. Clean the crankshaft with solvent, and blow out all oil passages with compressed air.
  2.  
  3. Use crocus cloth to remove any sharp edges, burrs or other imperfections which might damage the oil seal during installation or cause premature seal wear.
  4.  

Do not use crocus cloth to polish the seal surfaces. A finely polished surface may produce poor sealing or cause premature seal wear.

  1. Inspect the main and connecting rod journals for cracks, scratches, grooves or scores.
  2.  
  3. Measure the diameter of each journal in at least four places to determine the out-of-round, taper or undersize condition.
  4.  
  5. On an engine with a manual transmission, check the fit of the clutch pilot bearing in the bore of the crankshaft. A needle roller bearing and adapter assembly is used as a clutch pilot bearing. It is inserted directly into the engine crankshaft. The bearing and adapter assembly cannot be serviced separately.
  6.  
  7. Inspect the pilot bearing, when used, for roughness, evidence of overheating or loss of lubricant. Replace if any of these conditions are found.
  8.  

Main Bearings

See Figure 3

  1. Clean the bearing inserts and caps thoroughly in solvent, and dry them with compressed air.
  2.  

Do not scrape varnish or gum deposits from the bearing shells.

  1. Inspect each bearing carefully. Bearings that have a scored, chipped, or worn surface should be replaced.
  2.  



Click image to see an enlarged view

Fig. Fig. 3: Check the rod side clearance with a feeler gauge-use a small prybar to spread the rods

  1. The copper-lead bearing base may be visible through the bearing overlay in small localized areas. This may not mean that the bearing is excessively worn. It is not necessary to replace the bearing if the bearing clearance is within recommended specifications.
  2.  
  3. Check the clearance of each main bearing by using the following procedure:
    1. Place a piece of Plastigage® or equivalent on the bearing surface across the full width of the bearing cap and about 1/4 in. (6mm) off center.
    2.  
    3. Install the cap and tighten the bolts to specification. Do not turn the crankshaft while Plastigage® is in place.
    4.  
    5. Remove the cap. Using a Plastigage® scale, check the width of the Plastigage® at its widest point to get the minimum clearance. Check at its narrowest point to get the maximum clearance. The difference between the readings is the journal taper.
    6.  
    7. If clearance exceeds the specified limits, try a 0.001 in. (0.0254mm) or 0.002 in. (0.051mm) undersize bearing in combination with the standard bearing. Bearing clearance must be within the specified limits. If a standard and 0.002 in. (0.051mm) undersize bearing do not bring clearance within the desired limits, refinish the crankshaft journal, then install undersize bearings.
    8.  

  4.  
  5. Install all the bearing caps except the thrust bearing cap. Be sure the main bearing caps are installed in their original locations. Tighten the bearing cap bolts to specifications.
  6.  
  7. Install the thrust bearing cap with the bolts finger-tight.
  8.  

Refer to Rear Main Oil Seal removal and installation for special instructions on applying RTV sealer to the rear main bearing cup.

  1. Pry the crankshaft forward against the thrust surface of the upper half of the bearing.
  2.  
  3. Hold the crankshaft forward and pry the thrust bearing cap to the rear. This will align the thrust surfaces of both halves of the bearing.
  4.  
  5. Retain the forward pressure on the crankshaft. Tighten the cap bolts to specifications.
  6.  
  7. Check the crankshaft end-play using the following procedures:
    1. Force the crankshaft toward the rear of the engine.
    2.  
    3. Install a dial indicator so that the contact point rests against the crankshaft flange and the indicator axis is parallel to the crankshaft axis.
    4.  
    5. Zero the dial indicator. Push the crankshaft forward and note the reading on the dial.
    6.  
    7. If the end-play exceeds the wear limit listed in the Crankshaft and Connecting Rod Specifications chart, replace the thrust bearing. If the end-play is less than the minimum limit, inspect the thrust bearing faces fro scratches, burrs, nicks, or dirt. If the thrust faces are not damaged or dirty, then they probably were not aligned properly. Lubricate and install the new thrust bearing and align the faces.
    8.  

  8.  
  9. On engines with one piece rear main bearing oil seal, coat a new crankshaft rear oil seal with oil and install using a seal driver.
  10.  
  11. Inspect the seal to be sure it was not damaged during installation.
  12.  
  13. Install new bearing inserts in the connecting rods and caps. Check the clearance of each bearing.
  14.  
  15. After the connecting rod bearings have been fitted, apply a light coat of engine oil to the journals and bearings.
  16.  
  17. Turn the crankshaft throw to the bottom of its stroke. Push the piston all the way down until the rod bearing seats on the crankshaft journal.
  18.  
  19. Install the connecting rod cap. Tighten the nuts to specification.
  20.  
  21. After the piston and connecting rod assemblies have been installed, check the side clearance with a feeler gauge between the connecting rods on each connecting rod crankshaft journal. Refer to the Crankshaft and Connecting Rod specifications chart in this section.
  22.  
  23. Install the timing chain and sprockets or gears, cylinder front cover and crankshaft pulley and adapter, following steps under the cylinder front cover and timing chain installation procedure in this section
  24.  
  25. Re-grind the journals to give the proper clearance with the next undersize bearing. If the journal will not clean up to maximum undersize bearing available, replace the crankshaft.
  26.  
  27. Always reproduce the same journal shoulder radius that existed originally. Too small a radius will result in fatigue failure of the crankshaft. Too large a radius will result in bearing failure due to radius ride of the bearing.
  28.  
  29. After re-grinding the journals, chamfer the oil holes, then polish the journals with a #320 grit polishing cloth and engine oil. Crocus cloth may also be used as a polishing agent.
  30.  

BEARING REPLACEMENT



Gasoline Engines

See Figures 4, 5, 6, 7, 8 and 9

  1. Check the clearance of each main bearing by using the following procedure:
    1. Place a piece of Plastigage® or its equivalent, on bearing surface across full width of bearing cap and about 1 / 4 in. (6mm) off center.
    2.  
    3. Install cap and tighten bolts to specifications. Do not turn crankshaft while Plastigage® is in place.
    4.  
    5. Remove the cap. Using Plastigage® scale, check width of Plastigage® at widest point to get the minimum clearance. Check at narrowest point to get maximum clearance. Difference between readings is taper of journal.
    6.  
    7. If clearance exceeds specified limits, try a 0.001 in. (0.0254mm) or 0.002 in. (0.051mm) undersize bearing in combination with the standard bearing. Bearing clearance must be within specified limits. If standard and 0.002 in. (0.051mm) undersize bearing does not bring clearance within desired limits, refinish crankshaft journal, then install undersize bearings.
    8.  

  2.  

Refer to Rear Main Oil Seal removal and installation, for special instructions in applying RTV sealer to the rear main bearing cup.

  1. Install all the bearing caps except the thrust bearing cap. Be sure the main bearing caps are installed in their original locations. Tighten the bearing cap bolts to specifications.
  2.  
  3. Install the thrust bearing cap with the bolts finger-tight.
  4.  



Click image to see an enlarged view

Fig. Fig. 4: Check the crankshaft thrust bearing alignment as shown



Click image to see an enlarged view

Fig. Fig. 5: A dial gauge may be used to check crankshaft end-play



Click image to see an enlarged view

Fig. Fig. 6: Carefully pry the crankshaft back and forth while reading the dial gauge for play



Click image to see an enlarged view

Fig. Fig. 7: A dial gauge may also be used to check crankshaft run-out



Click image to see an enlarged view

Fig. Fig. 8: Mounting a dial gauge to read crankshaft run-out



Click image to see an enlarged view

Fig. Fig. 9: Turn the crankshaft slowly by hand while checking the gauge

  1. Pry the crankshaft forward against the thrust surface of the upper half of the bearing.
  2.  
  3. Hold the crankshaft forward and pry the thrust bearing cap to the rear. This will align the thrust surfaces of both halves of the bearing.
  4.  
  5. Retain the forward pressure on the crankshaft. Tighten the cap bolts to specifications.
  6.  
  7. Check the crankshaft end-play using the following procedures:
    1. Force the crankshaft toward the rear of the engine.
    2.  
    3. Install a dial indicator so that the contact point rests against the crankshaft flange and the indicator axis is parallel to the crankshaft axis.
    4.  
    5. Zero the dial indicator. Push the crankshaft forward and note the reading on the dial.
    6.  
    7. If the end-play exceeds the wear limit listed in the Crankshaft and Connecting Rod Specifications chart, replace the thrust bearing. If the end-play is less than the minimum limit, inspect the thrust bearing faces for scratches, burrs, nicks, or dirt. If the thrust faces are not damaged or dirty, then they probably were not aligned properly. Lubricate and install the new thrust bearing and align the faces following the procedure outlined earlier.
    8.  

  8.  
  9. On engines with one piece rear main bearing oil seal, coat a new crankshaft rear oil seal with oil and install using a seal driver. Inspect the seal to be sure it was not damaged during installation.
  10.  
  11. Install new bearing inserts in the connecting rods and caps. Check the clearance of each bearing, following the procedure (1a through 1d).
  12.  
  13. After the connecting rod bearings have been fitted, apply a light coat of engine oil to the journals and bearings.
  14.  
  15. Turn the crankshaft throw to the bottom of its stroke. Push the piston all the way down until the rod bearing seats on the crankshaft journal.
  16.  
  17. Install the connecting rod cap. Tighten the nuts to specification.
  18.  
  19. After the piston and connecting rod assemblies have been installed, check the side clearance with a feeler gauge between the connecting rods on each crankshaft journal. Refer to Crankshaft and Connecting Rod specifications chart in this section.
  20.  
  21. Install the timing chain, sprockets or gears, cylinder front cover and crankshaft pulley and adapter. Following the steps under Front Cover and Timing Chain Installation in this section.
  22.  

Diesel Engines

See Figures 10 and 11

  1. With the engine on a workstand, remove the front cover and timing gears. Remove the piston and rod assemblies. Identify each one for assembly.
  2.  
  3. Number and remove the main bearing caps. Remove the lower bearing inserts.
  4.  
  5. Use two of the main bearing cap bolts to wiggle the main caps loose, but be careful not to damage the bolt threads.
  6.  



Click image to see an enlarged view

Fig. Fig. 10: Use two bearing cap bolts to loosen the caps-diesel engine

  1. Lift out the crankshaft. Be sure to lift the crankshaft straight off the bearings to prevent damage to the thrust bearings.
  2.  



Click image to see an enlarged view

Fig. Fig. 11: Location of the piston cooling nozzles-diesel engine

  1. Remove the upper bearing inserts.
  2.  
  3. Remove the piston cooling nozzles by using a 3/18 in. (5mm) pin punch to push them out.
  4.  
  5. Support the crankshaft on V-blocks under Nos. 1 and 7 journals.
  6.  
  7. Mount a dial indicator contacting the center main bearing journal.
  8.  
  9. Rotate the crankshaft and note the reading. This is the crankshaft run-out.
  10.  
  11. Inspect all journals for wear, damage or overheating (blue color).
  12.  
  13. Check the clearance of each main bearing by using the following procedure:
    1. Place a piece of Plastigage® or its equivalent, on bearing surface across full width of bearing cap and about 1 / 4 in. (6mm) off center.
    2.  
    3. Install cap and tighten bolts to specifications. Do not turn crankshaft while Plastigage® is in place.
    4.  
    5. Remove the cap. Using Plastigage® scale, check width of Plastigage® at widest point to get the minimum clearance. Check at narrowest point to get maximum clearance. Difference between readings is taper of journal.
    6.  
    7. If clearance exceeds specified limits, try a 0.001 in. (0.0254mm) or 0.002 in. (0.051mm) undersize bearing in combination with the standard bearing. Bearing clearance must be within specified limits. If standard and 0.002 in. (0.051mm) undersize bearing does not bring clearance within desired limits, refinish crankshaft journal, then install undersize bearings.
    8.  

  14.  

Refer to Rear Main Oil Seal removal and installation, for special instructions in applying RTV sealer to rear main bearing cup.

  1. Install all the bearing caps except the thrust bearing cap. Be sure the main bearing caps are installed in their original locations. Tighten the bearing cap bolts to specifications.
  2.  
  3. Install the thrust bearing cap with the bolts finger-tight.
  4.  
  5. Pry the crankshaft forward against the thrust surface of the upper half of the bearing.
  6.  
  7. Hold the crankshaft forward and pry the thrust bearing cap to the rear. This will align the thrust surfaces of both halves of the bearing.
  8.  
  9. Retain the forward pressure on the crankshaft. Tighten the cap bolts to specifications.
  10.  
  11. Check the crankshaft end-play using the following procedures:
    1. Force the crankshaft toward the rear of the engine.
    2.  
    3. Install a dial indicator so that the contact point rests against the crankshaft flange and the indicator axis is parallel to the crankshaft axis.
    4.  
    5. Zero the dial indicator. Push the crankshaft forward and note the reading on the dial.
    6.  
    7. If the end-play exceeds the wear limit listed in the Crankshaft and Connecting Rod Specifications chart, replace the thrust bearing. If the end-play is less than the minimum limit, inspect the thrust bearing faces for scratches, burrs, nicks, or dirt. If the thrust faces are not damaged or dirty, then they probably were not aligned properly. Lubricate and install the new thrust bearing and align the faces following procedures above.
    8.  

  12.  
  13. On engines with one piece rear main bearing oil seal, coat a new crankshaft rear oil seal with oil and install using a seal driver. Inspect the seal to be sure it was not damaged during installation.
  14.  
  15. Install new bearing inserts in the connecting rods and caps. Check the clearance of each bearing, following the procedure.
  16.  
  17. After the connecting rod bearings have been fitted, apply a light coat of engine oil to the journals and bearings.
  18.  
  19. Turn the crankshaft throw to the bottom of its stroke. Push the piston all the way down until the rod bearing seats on the crankshaft journal.
  20.  
  21. Install the connecting rod cap. Tighten the nuts to specification.
  22.  
  23. After the piston and connecting rod assemblies have been installed, check the side clearance with a feeler gauge between the connecting rods on each connecting rod crankshaft journal. Refer to Crankshaft and Connecting Rod specifications chart in this section.
  24.  
  25. Install the timing chain and sprockets or gears, cylinder front cover and crankshaft pulley and adapter, following steps under Front Cover and Timing Chain Installation in this section.
  26.  

COMPLETING THE REBUILDING PROCESS



Fill the oil pump with oil, to prevent cavitating (sucking air) on initial engine start up. Install the oil pump and the pickup tube on the engine. Coat the oil pan gasket as necessary, and install the gasket and the oil pan. Mount the flywheel and the crankshaft vibration damper or pulley on the crankshaft.

Always use new bolts when installing the flywheel. Inspect the clutch shaft pilot bushing in the crankshaft. If the bushing is excessively worn, remove it with an expanding puller and a slide hammer, and tap a new bushing into place.

Position the engine, cylinder head side up. Lubricate the lifters, and install them into their bores. Install the cylinder head, and tighten it to the specified torque figure. Insert the pushrods (where applicable), and install the rocker shaft(s), if so equipped or position the rockers.

Install the intake and exhaust manifolds, the throttle body, the distributor (if applicable) and spark plugs. Mount all accessories and install the engine in the truck. Fill the radiator with coolant, and the crankcase with high quality engine oil.

BREAK-IN PROCEDURE



Start the engine, and allow it to run at low speed for a few minutes, while checking for leaks. Stop the engine, check the oil level, and fill as necessary. Restart the engine, and top off the cooling system to capacity. Check and adjust the ignition timing. Run the engine at low to medium speed (800-2,500 rpm) for approximately 1 / 2 hour, and re-tighten the cylinder head bolts. Road test the truck, and check again for leaks.

Some gasket manufacturers recommend not re-tightening the cylinder head(s) due to the composition of the head gasket. Follow the directions in the gasket set.

 
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