DennyWC

C5 2004 hatchback with 71,000 miles, started seeing light colored 1/4" size oil drops on garage floor under the oil pan. Is this worth fixing and average cost?

zachaeous

I would have the area cleaned and make sure where the oil is coming from. It could be many different things besides the oil pan gasket. Oil pressure sender leaking and running down dripping at the rear of the oil pan. Rear main seal starring to leak. Front crankshaft seal leaking, it will blow back and leak appearing to be the oil pan leaking.

If it is the upper oil pan gasket it requires lowering or dropping the front cradle to allow for changing the upper pan gasket. I would say you are looking at over a thousand dollars or more to change the pan gasket depending where you chose to have ot repaired.

DDaaryl

I have to agree that checking the oil pressure sending unit is the next logical step because gravity wins and the oil runs down there

Vetteman Jack

DennyWC

Thanks, check and found its the gasket. I got a call from the owner of The Corvette Shop, and he said here in Orange County, California it would be around $2000 or more to replace. He said, if I am not losing oil and have good oil pressure don't replace because it more than likely leak again. He said the gasket is the problem. Its aluminon with signal bead of sealer and it does not seal good like other gasket materials. I have great oil pressure and loss 1/16 qt over last 6 months. Think I will not try and replace.

6speedsteve

Maybe recheck the torque on the oil pan bolts, may help, may not, at least try that 1st.

Bill Curlee

LOL!!! I have to totally agree with 6speedsteve!!! The C5 & C6 OEM oil pan gasket are pretty robust and fail proof. Its a good design. Most all of the leaky oil pans that I have encountered were the result of loose main pan bolts. Just retorque to the OEM spec and see if your leak issue resolves its self.

If you have an A4 Auto trans, it makes the job a little more difficult because you have to deal with the trans oil cooler lines. Nothing too bad, just more to work around. DO NOT over torque the bolts!! later model C5 have a TWO piece oil pan. The lower section of the pan have very small fasteners. There spec is in INCH POUNDS. If you over torque them they will strip out.

Oil Pan to Engine block = 25 Nm or 18 ft/lb
Lower pan cover = 12 Nm or 106 inch pounds

IF, the gasket is damaged and or the rubber seal strip on the aluminum framed gasket is too hard, YEP, you will have to replace the gasket.

Give the retorque a try and save some cash. It can be done on jack stands in your drive way with basic hand tools.

DennyWC

Thanks All,
Retorque, I was going to ask if that was a possible fix. With only 70,000 miles, I was hoping that it was not a major fix and cost. Going to give it a try right after I get some of my HUNEY-DOSSSSSS done!

SilverC54me

Which Corvette shop diagnosed this? Which of the 2 gaskets did they say was bad, upper or lower? The upper is the block to pan and the lower is between the pan and lower pan (batwing).

Gary

Bill Curlee

Nothing major or difficult about a Retorque. You just need to get the right sockets, extensions, swivels and ratchets. Some of the bolts you may need to get with a socket swivel and may not be able to actually torque with a torque wrench but, once you get one properly torqued, you will be able to get the ones that require a swivel tighten properly by feel.

Oh, you will need a good light also. :-)

BC

TastyBacon

Be careful retorquing oil pan bolts. If it feels like it's turning a little *too* much, stop immediately! If the threads are oily, you can easily overtorque the bolts (without exceeding the factory torque spec!) and pull the threads out of the block. I know, because I did exactly that, trying to fix a leak. If possible it might even be worthwhile to completely remove the bolt and spray both it and the hole with brake/carb cleaner to remove oil, wipe the bolt and dry the hole with compressed air before reinstalling. Good luck.

voda1

Good advice, especially for the 2 bolts on rear of pan that screw into this cover (circled in blue):