I was told I have to replace the crankshaft seal and oil pan gasket on my 2000 chevy malibu and will cost approx. $380.00. Also is the rear main seal the same thing as the crankshaft seal??? Thanks!

Inside the oil pan. It is driven from the cam gear.

This may be from excessive pressure in the sump from blow-by from the compression process . It is from a blocked PCV valve that is not equalising that pressure. I have also known oil leaks to happen because the rear main bearing cap is leaking oil past the join around the bolts (loose) or no sealing compound used in assembling the rear main bearing.. I would look at the PCV valve as it is the cheapest test first.. Check that the oil is not coming from the front gear box seal or torque converter seal.

Dear Sir,
Here is the oil leaking Problem Identifying Technique

Engine oil leaks from the valve cover gasket are common.

The intake manifold plenum gasket may leak and cause increased oil consumption/burning and a spark knock during acceleration; the gasket should be replaced.

External oil leaks from valve cover gaskets, intake gaskets (front or rear), and the rear crankshaft (rear main) seal area are common. The rear main seal is an unlikely source. Normally, the bearing cap mating surfaces (as well as the sealing surface between the oil pan and bearing cap) are the source for the leaks.

Engine oil leaks at the distributor can be misdiagnosed as leaks from theintake manifold seal, oil pan gasket, or rear crankshaft (rear main) seal. A revised distributor is available if oil is found inside the distributor.

If the oil filter casing shows signs of distortion from excessive oil pressure, theoil pump should be replaced.

Often misdiagnosed as a leaking oil filter gasket, the oil filter adapter can seep from between the adapter and engine block.

Carbon buildup on the top of the piston is common. As the buildup increases with mileage and over time, symptoms may vary from light ticking, to ticking/hammering, to hammering/knocking noises. Fuel injector cleaner often solves the problem.

I think it helps to analyse u r Problem

Are you sure have a leak,? you saw it? they usually don't leak only from the valve cover gasket.
If you see oil drip by the passenger side of the oil pan the leak could be the crankshaft seal.
if the oil is in the center of the engine rear main seal is the problem.
If al around the oil pan is wet with oil but the oil do not make it to the floor, then the person who is doing the oil changes is not cleaning properly.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/flavio_517b938f50183b92

of course there is ! look at where the leak is with the vehicule raised high enough and some good light. a pan gasket is going all around the pan and higher, the seal is there surrounding the crankshaft

If it's oil, it's coming from the rear main seal.. I would go with this idea.

The seal doesn't cost much but the labor to get to it does.

To give you an idea what is involved the procedure is illustrated below from the service manual:

Removal & Installation 3.8L Engine To Remove:

1. Drain the engine coolant.
2. Drain the engine oil.
3. Remove the oil pan.
4. Remove the engine flywheel.
5. Remove the rear oil seal housing and gasket. Rear seal removal 3.8L
   
   
6. Remove the rear main seal by placing the housing face down on 2 blocks of wood. Using a drift tool and hammer tap the seal out of the housing.

To Install:
NOTE: Do not lubricate the rear main oil seal or the installation tool. Do not touch the sealing lip of the rear main seal once the protective sleeve is removed.
NOTE: Use a clean lint free cloth to clean the crankshaft sealing surface. Remove sharp edges or burrs that could damage the rear main oil seal. Remove burrs or sharp edges with a crocus cloth.

1. Carefully remove the rear oil seal from the protective sleeve.
2. Install the oil seal onto the seal driver EN-47623 or equivalent by placing the seal at an angle and twisting until it is fully seated.
3. Install the seal into the housing using the seal driver EN-47623 or equivalent and driver handle J-8092 or equivalent. Apply downward force until the seal is seated. NOTE: Ensure that the housing gasket is installed correctly and that the oil passages are not blocked.
   
4. Using a new gasket Install the rear oil seal housing on the engine being careful not damage the rear main seal. NOTE: The plastic inserts are used in production and are not needed for assembly.
   
5. Hand tighten the bolts. Rear seal housing alignment 3.8L
   
   
6. Place a straight edge on the crankshaft rear oil seal housing flange and the engine block oil pan flange. Using a feeler gauge check that there is no more than .0004 in (0.10 mm) step on each side. Rotate the housing to make the steps equal on both sides.
7. Tighten the housing bolts 11 ft-lb (15 Nm) plus an additional 50 degrees.
8. Ensure that the housing did not move out of specification. Repeat step 6 if the oil seal housing is not within the specified range. Replace the rear oil seal housing if the specified measurement can not be reached.
9. Install the flywheel.
10. Install the oil pan.
11. Fill the engine oil and the cooling system.
12. Check for leaks

5.3L Engine To Remove:

1. Remove the flywheel from the crankshaft.
2. Remove and discard the crankshaft rear oil seal from the rear cover.

To Install:

1. Use clean engine oil to lubricate the outside diameter of the crankshaft rear oil seal and rear cover oil seal bore.
2. Install the tapered cone and bolts of a J 41479 or equivalent crankshaft rear oil seal installer onto the crankshaft.
3. Place the crankshaft rear oil seal onto the tapered cone.
4. Install the threaded rod of the J 41479 crankshaft rear oil seal installer into the tapered cone. Rear main seal installer 5.3L
   
   
5. Install the crankshaft rear oil seal by turning the handle of the J 41479 clockwise.
6. Remove the J 41479 crankshaft rear oil seal installer from the crankshaft.
7. Install the flywheel onto the crankshaft.

--- I'm not sure what the exact cost would be as the hours were not listed for this procedure on my online resource.

It could be from a head gasket but those are usually easier to see. It could also be from the front or rear main seals that seal oil around the crankshaft. Rear main seal will usually drip out of the bell housing cover and the front main seal will drip behind the harmonic balancer which is the part that runs most of your fan and power steering belts.

this truck is equipped with an aluminum oil pan you could have 1 or several things going on... a stripped drain plug which is causing it to leak or it may be a leaking front seal or a rear main seal. If it is a front seal it is not to labor intensive. But if it is a rear main seal leaking it will require the transmission to be removed since the seal is a 1 piece rear main

If you can estimate the labor rate in your are you should be able to get a good idea of the cost.

Parts Information

Part OEM Part Price
Crankshaft Main Bearing Seal
Rear Main Seal 12554314 $37.30



Crankshaft Main Bearing Seal
Replace Rear Main Seal
With Auto Trans 8.7 Hrs
Note
With Skid Plate, Add 0.4 hrs
With Manual Trans
Hydramatic MG5/MY2/M50 6.5 hrs
New Venture MW2 5.2 hrs
Note
With Skid Plate, 0.4 hrs

Dear Sir,
Here is the oil leaking Problem Identifying Technique

Engine oil leaks from the valve cover gasket are common.

The intake manifold plenum gasket may leak and cause increased oil consumption/burning and a spark knock during acceleration; the gasket should be replaced.

External oil leaks from valve cover gaskets, intake gaskets (front or rear), and the rear crankshaft (rear main) seal area are common. The rear main seal is an unlikely source. Normally, the bearing cap mating surfaces (as well as the sealing surface between the oil pan and bearing cap) are the source for the leaks.

Engine oil leaks at the distributor can be misdiagnosed as leaks from the intake manifold seal, oil pan gasket, or rear crankshaft (rear main) seal. A revised distributor is available if oil is found inside the distributor.

If the oil filter casing shows signs of distortion from excessive oil pressure, the oil pump should be replaced.

Often misdiagnosed as a leaking oil filter gasket, the oil filter adapter can seep from between the adapter and engine block.

Carbon buildup on the top of the piston is common. As the buildup increases with mileage and over time, symptoms may vary from light ticking, to ticking/hammering, to hammering/knocking noises. Fuel injector cleaner often solves the problem.

I think it helps to analyse u r Problem