It's like a rattling loud noise that comes out from the camshaft sprockets and timing belt on my 1998 dodge caravan 2.4 engine. it started while running on the road.

1. Using sprocket installation tool No. 6792 or equivalent, press the crankshaft sprocket onto the crankshaft.
2. Install the camshaft sprockets onto the camshafts. Install and tighten the sprocket retaining bolts to 75 ft. lbs. (101 Nm).

Fig. Fig. 4: Proper camshaft sprocket alignment for timing belt installation

1. Install the crankshaft sprocket. Set the crankshaft sprocket to Top Dead Center (TDC) by aligning the notch on the sprocket with the arrow on the oil pump housing.
2. Set the camshafts to align the timing marks on the sprockets.
3. Move the crankshaft to 1 / 2 notch before TDC.
4. Install the timing belt starting at the crankshaft, then around the water pump sprocket, idler pulley, camshaft sprockets, and then around the tensioner pulley.
5. Move the crankshaft sprocket to TDC to take up the belt slack.
6. Install the tensioner to the engine block, but do not tighten.
7. Using a torque wrench on the tensioner pulley apply 250 inch lbs. (28 Nm) of tighten to the tensioner pulley.
8. With torque being applied to the tensioner pulley, move the tensioner up against the tensioner pulley bracket and tighten the fasteners to 275 inch lbs. (31 Nm).
9. Remove the tensioner plunger pin. The tension is correct when the plunger pin can be removed and replaced easily.
10. Rotate the crankshaft 2 revolutions and recheck the timing marks. Wait several minutes and then recheck that the plunger pin can easily be removed and installed.
11. Reinstall the front timing belt cover(s).
12. Reinstall the engine mount bracket.
13. Reinstall the right engine mount.
14. Remove the floor jack from under the vehicle.
15. Install the crankshaft damper and tighten to 105 ft. lbs. (142 Nm).
16. Install the accessory drive belts and adjust to the proper tension.
17. Install the right inner splash shield.
18. Reconnect the negative battery cable.
19. Check for leaks and proper engine operation.

Source: Autozone.com

It's probably either the camshaft or bearings, or the crankshaft or bearings.

Is that the noise you mean? Rough and loud? Yeah, it makes you wonder if the timing is off by a tooth or two, doesn't it?
There may be a viewing/access plug on the camshaft sprocket cover to see the cam sprocket timing mark, when the crankshaft is turned to TDC, or 0 degrees. If no plug or access to see the cam sprocket, it might be wise to re-check the timing. Is there any difficulty in starting the engine? Or does it seem to run warmer than normal? Was the belt tension set correctly? Just a few things to consider, good luck.

Is this what you needed?

Fig. Fig. 14: Sprocket timing for belt installation-3.0L engines

Fig. Fig. 15: Secure the sprocket when removing or installing the nut-3.0L engines

Fig. Fig. 16: Timing belt tensioner-3.0L engines

Fig. Fig. 17: Positioning the tensioner-3.0L engines
The timing belt can be inspected by removing the upper (front outer) timing cover.

1. Disconnect the negative battery cable.
2. Remove the accessory drive belts.
3. Remove the timing belt covers.
4. Identify the timing belt running direction to avoid reversal during installation.
5. Loosen timing belt tensioner bolt and remove timing belt.
6. Remove the crankshaft sprocket flange.

To install:

1. Rotate the crankshaft sprocket until timing mark on crankshaft sprocket is lined up with the oil pump timing mark at 1 o'clock position.
2. Rotate the (inner) camshaft sprocket until mark on (inner) camshaft sprocket is lined up with the timing mark on alternator bracket.
3. Rotate the (outer) camshaft sprocket (radiator side) until mark on the sprocket is lined up with the timing mark on the timing belt inner cover. Refer to timing belt illustration.
4. Install the timing belt on the crankshaft sprocket while maintaining pressure on the tensioner side.
5. Position the timing belt over the camshaft sprocket (radiator side). Next, position the belt under the water pump pulley, then over the (inner) sprocket and finally over the tensioner.
6. Apply rotating force in the opposite direction to the camshaft sprocket (radiator side) to create tension on the timing belt tension side.
7. Rotate the crankshaft in a clockwise direction and recheck engine timing marks.
8. Install the crankshaft sprocket flange.
9. Loosen the tensioner bolt and allow tensioner spring to tension the belt.
10. Again rotate the crankshaft in a clockwise direction (2) full turns. Recheck the engine timing. Tighten the tensioner bolt to 23 ft. lbs. (31 Nm).
11. Install the timing covers.
12. Install the accessory drive belts.
13. Connect battery negative cable.

I Show Only a 3.2L For this Year this Will Guide you Enjoy your Work RejakWilson


REMOVAL

CAUTION: The following procedure can only be used when the camshaft sprockets HAVE NOT BEEN LOOSENED or removed from the camshafts. Refer to Camshaft Gear/Sprocket and Timing Components, if sprocket(s) or camshaft(s) have been loosened or removed.

CAUTION: The 3.2/3.5L are NOT freewheeling engines. Therefore, care should be taken not to rotate the camshafts or crankshaft with the timing belt removed.

1. Disconnect negative cable from remote jumper terminal.
2. Remove upper radiator crossmember.
3. Disconnect fan module electrical connector.
4. Remove cooling fan module and accessory drive belts.
5. Remove crankshaft damper and front timing belt covers.
6. Mark belt running direction, if timing belt is to be reused.

CAUTION: When aligning timing marks, always rotate engine by turning the crankshaft. Failure to do so will result in valve and/or piston damage.

Fig. 94

1. Rotate engine clockwise until crankshaft mark aligns with the TDC mark on oil pump housing and the camshaft sprocket timing marks are between the marks on the rear covers (Fig. 94).

CAUTION: Align the camshaft sprockets between the marks on rear belt covers before timing belt removal or damage to valve and/or pistons could occur.

1. Using a ink or paint marker; mark the exact position of the camshaft sprocket timing mark relative to the two timing marks on the rear timing cover.

NOTE: When timing belt tensioner is removed from engine, always store in the vertical (plunger facing upward) position

Fig. 95

1. Remove the timing belt tensioner (Fig. 95) and remove timing belt.

TIMING BELT TENSIONER

1. When tensioner is removed from the engine it is necessary to compress the plunger into the tensioner body.

CAUTION: Compress the tensioner slowly, as damage to tensioner could result.

Fig. 96

1. Place the tensioner into a vise and SLOWLY compress the plunger (Fig. 96). Total bleed down of tensioner should take about 5 minutes.

CAUTION: Index the tensioner in the vise the same way it is installed on the engine. This is to ensure proper pin orientation when tensioner is installed on the engine.

1. When plunger is compressed into the tensioner body install a pin through the body and plunger to retain plunger in place until tensioner is installed.

NOTE: When timing belt tensioner is removed from engine, always store in the vertical (plunger facing upward) position.

INSTALLATION

CAUTION: This procedure can only be used when the camshaft sprockets HAVE NOT BEEN LOOSENED or removed from the camshafts.

CAUTION: If camshafts have moved from the timing marks, always rotate camshaft towards the direction nearest to the timing marks (DO NOT TURN CAMSHAFTS A FULL REVOLUTION OR DAMAGE to valves and/or pistons could result).


Fig. 97

1. Align the crankshaft sprocket with the TDC mark on oil pump cover (Fig. 97).
2. Align the camshaft sprockets (to reference mark made upon removal) between the marks on the rear covers (Fig. 94).
3. Install the timing belt starting at the crankshaft sprocket going in a counterclockwise direction (Fig. 97). Install the belt around the last sprocket. Maintain tension on the belt as it is positioned around the tensioner pulley.
4. Holding the tensioner pulley against the belt, Install the tensioner into the housing and tighten to 28 Nm (250 in. lbs.) . Each camshaft sprocket mark should still fall between the cover marks.
5. When tensioner is in place pull retaining pin to allow the tensioner to extend to the pulley bracket.
6. Rotate crankshaft sprocket 2 revolutions and check the timing marks on the camshafts and crankshaft. The marks should line up within their respective locations (Fig. 97). If marks do not line up, repeat procedure.
7. Install timing belt covers and crankshaft damper.
8. Install accessory drive belts and cooling fan module.
9. Install upper radiator crossmember.
10. Connect negative cable to remote jumper terminal.
11. Start engine and allow to idle for approximately 1 minute. If a noise is present from the timing belt/tensioner, air has possibly entered the tensioner.

1. To remove air from tensioner; using a DRB III, operate the engine at speed of 1600-2000 RPM for 10 minutes. This will purge air from tensioner.

NOTE: If air is present, the timing belt tensioner will be soft and may generate noise. This noise should disappear after no more than 15 minutes of engine running time.

Timing Belt Removal & Installation 3.0L Engine To Remove:
Exploded view of the timing belt and sprocket assembly (3.0L engine)

1. Disconnect the negative battery cable.
2. Remove the accessory drive belts. Remove the engine mount insulator from the engine support bracket.
3. Remove the engine support bracket. Remove the crankshaft pulleys and torsional damper. Remove the timing belt covers.
4. Rotate the crankshaft until the sprocket timing marks are aligned. The crankshaft sprocket timing mark should align with the oil pump timing mark. The rear camshaft sprocket timing mark should align with the generator bracket timing mark and the front camshaft sprocket timing mark should align with the inner timing belt cover timing mark.
5. If the belt is to be reused, mark the direction of rotation on the belt for installation reference. Mark the direction of travel for the timing belt for correct installation
   
6. Loosen the timing belt tensioner bolt and remove the timing belt.
7. If necessary, remove the timing belt tensioner. Turn the center tensioner pulley bolt until the timing belt has enough slack . . .
   . . . then slide the timing belt off of the camshaft sprockets
   
8. Remove the crankshaft sprocket flange shield and crankshaft sprocket.
9. Hold the camshaft sprocket using spanner tool MB990775 or equivalent, and remove the camshaft sprocket bolt and washer. Remove the camshaft sprocket.

To Install:

1. Install the camshaft sprocket on the camshaft with the retaining bolt and washer. Hold the camshaft sprocket using spanner tool MB990775 or equivalent, and tighten the bolt to 70 ft. lbs. (95 Nm).
2. Install the crankshaft sprocket.
3. If removed, install the timing belt tensioner and tensioner spring. Hook the spring upper end to the water pump pin and the lower end to the tensioner bracket with the hook out.
4. Turn the timing belt tensioner counterclockwise full travel in the adjustment slot and tighten the bolt to temporarily hold it in this position.
5. Rotate the crankshaft sprocket until its timing mark is aligned with the oil pump timing mark.
6. Rotate the rear camshaft sprocket until its timing mark is aligned with the timing mark on the generator bracket.
7. Rotate the front (radiator side) camshaft sprocket until its mark is aligned with the timing mark on the inner timing belt cover.
8. Install the timing belt on the crankshaft sprocket while keeping the belt tight on the tension side. NOTE: If the original belt is being reused, be sure to install it in the same rotational direction.
   
9. Position the timing belt over the front camshaft sprocket (radiator side). Next, position the belt under the water pump pulley, then over the rear camshaft sprocket and finally over the tensioner. CAUTION
   If any binding is felt when adjusting the timing belt tension by turning the crankshaft, STOP turning the engine, because the pistons may be hitting the valves.
   Rent or borrow the special tool to hold the camshaft sprockets steady . . .
   . . . while loosening the center retaining bolt on the camshaft pulley, then . . .
   . . . remove the camshaft sprocket from the end of the camshaft
   Timing belt tensioner and spring positions
   Timing belt routing and timing mark locations
   
   
10. Apply rotating force in the opposite direction to the front camshaft sprocket (radiator side) to create tension on the timing belt tension side. Check that all timing marks are aligned.
11. Install the crankshaft sprocket flange.
12. Loosen the tensioner bolt and allow the tensioner spring to tension the belt.
13. Rotate the crankshaft two full turns in a clockwise direction. Turn the crankshaft smoothly and in a clockwise direction only.
14. Again line up the timing marks. If all marks are aligned, tighten the tensioner bolt to 250 in. lbs. (28 Nm). Otherwise repeat the installation procedure.
15. Install the timing belt covers. Install the engine support bracket. Tighten the support bracket mounting bolts to 35 ft. lbs. (47 Nm).
16. Install the engine mount insulator, torsional damper and crankshaft pulleys. Tighten the crankshaft pulley bolt to 112 ft. lbs. (151 Nm).
17. Install the accessory drive belts.
18. Reconnect the negative battery cable.
19. Run the engine and check for proper operation.

Timing chain is only available in the 3.3L and 3.8L engines.

Yours has a belt. (if you're SURE its a 3.0L)

Here is the info on changing it...

3.0L Engine
The timing belt can be inspected by removing the upper front outer timing belt cover.
Working on any engine (especially overhead camshaft engines) requires much care be given to valve timing. It is good practice to set the engine up at TDC No. 1 cylinder firing position before beginning work. Verify that all timing marks on the crankshaft and camshaft sprockets are properly aligned before removing the timing belt and starting camshaft service. This serves as a point of reference for all work that follows. Valve timing is very important and engine damage will result if the work is incorrect.

1. Disconnect the negative battery cable.
2. Remove the accessory drive belts. Remove the engine mount insulator from the engine support bracket.
3. Remove the engine support bracket. Remove the crankshaft pulleys and torsional damper. Remove the timing belt covers.
4. Rotate the crankshaft until the sprocket timing marks are aligned. The crankshaft sprocket timing mark should align with the oil pump timing mark. The rear camshaft sprocket timing mark should align with the generator bracket timing mark and the front camshaft sprocket timing mark should align with the inner timing belt cover timing mark.
5. If the belt is to be reused, mark the direction of rotation on the belt for installation reference.
6. Loosen the timing belt tensioner bolt and remove the timing belt.
7. If necessary, remove the timing belt tensioner.
8. Remove the crankshaft sprocket flange shield and crankshaft sprocket.
9. Hold the camshaft sprocket using spanner tool MB990775, or equivalent, and remove the camshaft sprocket bolt and washer. Remove the camshaft sprocket.
10. To install:
    
11. Install the camshaft sprocket on the camshaft with the retaining bolt and washer. Hold the camshaft sprocket using spanner tool MB990775, or equivalent, and tighten the bolt to 70 ft. lbs. (95 Nm).
12. Install the crankshaft sprocket.
13. If removed, install the timing belt tensioner and tensioner spring. Hook the spring upper end to the water pump pin and the lower end to the tensioner bracket with the hook out.
14. Turn the timing belt tensioner counterclockwise full travel in the adjustment slot and tighten the bolt to temporarily hold it in this position.
15. Rotate the crankshaft sprocket until its timing mark is aligned with the oil pump timing mark.
16. Rotate the rear camshaft sprocket until its timing mark is aligned with the timing mark on the generator bracket.
17. Rotate the front (radiator side) camshaft sprocket until its mark is aligned with the timing mark on the inner timing belt cover.
18. Install the timing belt on the crankshaft sprocket while keeping the belt tight on the tension side.
19. Position the timing belt over the front camshaft sprocket (radiator side). Next, position the belt under the water pump pulley, then over the rear camshaft sprocket and finally over the tensioner.
20. Apply rotating force in the opposite direction to the front camshaft sprocket (radiator side) to create tension on the timing belt tension side. Check that all timing marks are aligned.
21. Install the crankshaft sprocket flange.
22. Loosen the tensioner bolt and allow the tensioner spring to tension the belt.
23. Rotate the crankshaft 2 full turns in a clockwise direction. Turn the crankshaft smoothly and in a clockwise direction only.
24. Align the timing marks. If all marks are aligned, tighten the tensioner bolt to 250 inch lbs. (28 Nm). Otherwise repeat the installation procedure.
25. Install the timing belt covers. Install the engine support bracket. Tighten the support bracket mounting bolts to 35 ft. lbs. (47 Nm).
26. Install the engine mount insulator, torsional damper and crankshaft pulleys. Tighten the crankshaft pulley bolt to 112 ft. lbs. (151 Nm).
27. Install the accessory drive belts and adjust them to the proper tension.
28. Reconnect the negative battery cable.
29. Run the engine and check for proper operation. Road test the vehicle.

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2.4L Engine
NOTE You may need DRB scan tool to perform the crankshaft and camshaft relearn alignment procedure.

1. Remove or disconnect the following:
   
   • Negative battery cable
     
   • Right front wheel and inner splash shield
     
   • Accessory drive belts
     
   • Crankshaft damper
     
   • A/C compressor/alternator tensioner and pulley assembly
     
   • Lower front timing cover
     
   • Upper front timing cover
     
   • Right engine mount
     
   • Engine mount bracket
     
   
   NOTE This is an interference engine. Do not rotate the crankshaft or the camshafts after the timing belt has been removed. Damage to the valve components may occur. Before removing the timing belt, always align the timing marks.
   
2. Rotate the crankshaft until the Top Dead Center (TDC) mark on the oil pump housing aligns with the TDC mark on the camshaft sprocket (located on the trailing edge of the tooth).
   
3. Loosen the timing belt tensioner lock bolt.
   
4. Insert a 6mm Allen wrench into the hexagon opening located on the top plate of the belt tensioner pulley. Rotate the top plate clockwise until there is enough slack to remove the belt.
   
5. If necessary, remove the camshaft timing belt sprockets.
   
6. If necessary, remove the crankshaft timing belt sprocket using removal tool No. 6793, or equivalent.
   
7. Place the tensioner into a soft-jawed vise to compress the tensioner.
   
8. After compressing the tensioner, insert a pin (a 5/64 in. Allen wrench will also work) into the plunger side hole to retain the plunger until installation.
   

Camshaft and crankshaft alignment marks—2.4L engine




To lock the timing belt tensioner, be sure to fully insert the smaller Allen wrench into the tensioner as shown—2.4L engine





Installation of the timing belt, notice the camshaft alignment— 2.4L (VIN B) engine


To install:

1. If necessary, use tool No. 6792, or equivalent, to install the crankshaft timing belt sprocket onto the crankshaft.
   
2. If necessary, install the camshaft sprockets onto the camshafts. Install and tighten the camshaft sprocket bolts to 75 ft. lbs. (101 Nm).
   
3. Set the crankshaft sprocket to Top Dead Center (TDC) by aligning the notch on the sprocket with the arrow on the oil pump housing.
   
4. Set the camshafts timing marks so the exhaust camshaft is 1/2 notch below intake camshaft sprocket. Make sure the arrows on both camshaft sprockets are facing up
   
5. Install the timing belt starting at the crankshaft, then around the water pump sprocket, idler pulley, camshaft sprockets and around the tensioner pulley.
   
6. Move the exhaust camshaft sprocket counterclockwise to take up the belt slack.
   
7. Insert a 6mm Allen wrench into the hexagon opening located on the top plate of the belt tensioner pulley. Rotate the top plate counterclockwise until there is no slack on the belt. The tensioner setting notch will start to move clockwise. Watch the notch and continue rotating the top plate counterclockwise until the setting notch is aligned with the spring tang. Using the Allen wrench to prevent the top plate from moving, tighten the tensioner lock bolt to 220 inch lbs. (25 Nm). The setting notch and spring tang should remain aligned after the lock nut is tightened.
   
8. Rotate the crankshaft 2 revolutions and recheck the timing marks.
   
9. Check the spring tang is within the tolerance window. If not within the window, reinsert the Allen wrench and into the hexagon opening located on the top plate of the belt tensioner pulley. Rotate the top plate counterclockwise until there is no slack on the belt. The tensioner setting notch will start to move clockwise. Watch the notch and continue rotating the top plate counterclockwise until the setting notch is aligned with the spring tang. Using the Allen wrench to prevent the top plate from moving, tighten the tensioner lock bolt to 220 inch lbs. (25 Nm). The setting notch and spring tang should remain aligned after the lock nut is tightened.
   
10. Install the engine mount bracket.
    
11. Install the front timing belt covers.
    
12. Install the A/C compressor/alternator tensioner and pulley assembly.
    
13. Install the right engine mount.
    
14. Install the crankshaft damper
    
15. Install the accessory drive belts and adjust to the proper tension.
    
16. Install the right inner splash shield and wheel.
    
17. Reconnect the negative battery cable.
    
18. Perform the crankshaft and camshaft relearn alignment procedure using the DRB scan tool, or equivalent
    

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Fix your car right away by clicking the link I attached 1998 Dodge Caravan Service Repair Factory Manual INSTANT DOWNLOAD

Alright, here's a pic of the mechanicals:



The bad news is on your vechile you have to remove the timing belt, but here's a step by step.

1. Disconnect the negative battery cable.
2. Remove the drive belts.
3. Drain the cooling system.

CAUTION When draining coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

1. Remove the timing case cover and timing belt. Refer to Timing Belt Covers and Timing Belt Removal procedures.
2. Remove the pump assembly mounting bolts.
3. Separate the pump assembly from water pipe and remove.
4. Clean gasket and O-ring mounting surfaces.
5. Install a new O-ring on water pipe and lubricate with water.
6. Install a new gasket on pump body.
7. Press the water pump assembly into water pipe.
8. Install pump mounting bolts and tighten to 27 Nm (20 ft. lbs.).
9. Install timing belt and cover. Refer to Timing Belt procedures.
10. Install drive belts.
11. Fill the cooling system

To remove timing:

The timing belt can be inspected by removing the upper (front outer) timing cover.

1. Disconnect the negative battery cable.
2. Remove the accessory drive belts.
3. Remove the timing belt covers.
4. Identify the timing belt running direction to avoid reversal during installation.
5. Loosen timing belt tensioner bolt and remove timing belt.
6. Remove the crankshaft sprocket flange.

To install:

1. Rotate the crankshaft sprocket until timing mark on crankshaft sprocket is lined up with the oil pump timing mark at 1 o'clock position.
2. Rotate the (inner) camshaft sprocket until mark on (inner) camshaft sprocket is lined up with the timing mark on alternator bracket.
3. Rotate the (outer) camshaft sprocket (radiator side) until mark on the sprocket is lined up with the timing mark on the timing belt inner cover. Refer to timing belt illustration.
4. Install the timing belt on the crankshaft sprocket while maintaining pressure on the tensioner side.
5. Position the timing belt over the camshaft sprocket (radiator side). Next, position the belt under the water pump pulley, then over the (inner) sprocket and finally over the tensioner.
6. Apply rotating force in the opposite direction to the camshaft sprocket (radiator side) to create tension on the timing belt tension side.
7. Rotate the crankshaft in a clockwise direction and recheck engine timing marks.
8. Install the crankshaft sprocket flange.
9. Loosen the tensioner bolt and allow tensioner spring to tension the belt.
10. Again rotate the crankshaft in a clockwise direction (2) full turns. Recheck the engine timing. Tighten the tensioner bolt to 23 ft. lbs. (31 Nm).
11. Install the timing covers.
12. Install the accessory drive belts.
13. Connect battery negative cable.

Hope this helps.