99 Oil Pan Gasket Replacement
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Melting Slicks
Joined: May 2013
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From: New Jersey
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St. Jude Donor '25
99 Oil Pan Gasket Replacement
I developed a small leak on my 99, most noticeable while parking it on an angle, took it into the Dealership today for a diag and they quoted be $1,815 to replace the oil pan gasket, perform an alignment, and oil change.
I am thinking this is crazy, no?
I am thinking this is crazy, no?
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Joined: Feb 2023
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From: Denver, CO
Thread Starter
Melting Slicks
Joined: May 2013
Posts: 2,982
Likes: 1,406
From: New Jersey
2025 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '25
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Joined: Mar 2007
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From: Norfolk, UK
A related question on that, please. My car is having the harmonic balancer replaced soon, so I believe I'm correct in saying that they'll have to do some of that anyway in order to do that job. They've advised it may be wise to replace the front seal as well as the upper and lower oil pan gaskets. How much work/time, roughly, do you think is being saved doing the oil pan gaskets while doing a harmonic balancer, vs a car going in for just the gaskets? From what I have seen, the front seal can probably only be done when you have removed the balancer, is that correct, please?
Intermediate
Joined: Mar 2023
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A related question on that, please. My car is having the harmonic balancer replaced soon, so I believe I'm correct in saying that they'll have to do some of that anyway in order to do that job. They've advised it may be wise to replace the front seal as well as the upper and lower oil pan gaskets. How much work/time, roughly, do you think is being saved doing the oil pan gaskets while doing a harmonic balancer, vs a car going in for just the gaskets? From what I have seen, the front seal can probably only be done when you have removed the balancer, is that correct, please?
oil pump, etc. hb is a big job. Set a budget and do every thorn you can!!
.
Joined: Apr 2013
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From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
A related question on that, please. My car is having the harmonic balancer replaced soon, so I believe I'm correct in saying that they'll have to do some of that anyway in order to do that job. They've advised it may be wise to replace the front seal as well as the upper and lower oil pan gaskets. How much work/time, roughly, do you think is being saved doing the oil pan gaskets while doing a harmonic balancer, vs a car going in for just the gaskets? From what I have seen, the front seal can probably only be done when you have removed the balancer, is that correct, please?
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Joined: Mar 2007
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From: Norfolk, UK
Thanks for your thoughts. The additional things on the list so far are the Acc and A/c belts, plus associated tensioners and idlers, water pump, front seal, oil change with new oil filter... the oil pressure sensor is pegged at max, so I know that needs doing... and the aforementioned upper and lower oil pan gaskets have been raised as probables as well. With the car up in the air so you can walk under it, there's evidence of an oil leak from somewhere but I'm somewhat sure it's only when it's running; there's no sign of oil on the ground where it gets parked and based on the level on the dipstick whenever I check, it's not obviously going down much at all over time.
Is the lower oil pan gasket a less involved job than the upper one, please?
Is the lower oil pan gasket a less involved job than the upper one, please?
Intermediate
Joined: Mar 2023
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When your buying parts like this, here’s the order:
1. Rockauto
2. gmparts direct (just slightly out of your state so the shipping is cheaper than the sales tax)
3. summit Racing (which is always the most expensive)
personally, i don’t trust Amazon. They sell fake Chinese parts.
1. Rockauto
2. gmparts direct (just slightly out of your state so the shipping is cheaper than the sales tax)
3. summit Racing (which is always the most expensive)
personally, i don’t trust Amazon. They sell fake Chinese parts.
.
Joined: Apr 2013
Posts: 5,020
Likes: 1,149
From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
Thanks for your thoughts. The additional things on the list so far are the Acc and A/c belts, plus associated tensioners and idlers, water pump, front seal, oil change with new oil filter... the oil pressure sensor is pegged at max, so I know that needs doing... and the aforementioned upper and lower oil pan gaskets have been raised as probables as well. With the car up in the air so you can walk under it, there's evidence of an oil leak from somewhere but I'm somewhat sure it's only when it's running; there's no sign of oil on the ground where it gets parked and based on the level on the dipstick whenever I check, it's not obviously going down much at all over time.
Is the lower oil pan gasket a less involved job than the upper one, please?
Is the lower oil pan gasket a less involved job than the upper one, please?
.
Joined: Apr 2013
Posts: 5,020
Likes: 1,149
From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
Instructor
Joined: Mar 2007
Posts: 108
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From: Norfolk, UK
Already been building a shopping list of parts on RockAuto 
. I'm mostly there but will have a couple more questions to ask the forum at some point soon. May start a new thread for those, rather than continuing to hi-jack this one as we go further off topic!
Thank you. So (and without holding you to anything!) would you suggest that even with the work being done to replace the HB, such as dropping the front sub-frame and removing the steering rack, etc, replacing the upper oil pan gasket is enough extra steps beyond that it's still a big job even from that point and not something to take on lightly, please?
. I'm mostly there but will have a couple more questions to ask the forum at some point soon. May start a new thread for those, rather than continuing to hi-jack this one as we go further off topic! Thank you. So (and without holding you to anything!) would you suggest that even with the work being done to replace the HB, such as dropping the front sub-frame and removing the steering rack, etc, replacing the upper oil pan gasket is enough extra steps beyond that it's still a big job even from that point and not something to take on lightly, please?
.
Joined: Apr 2013
Posts: 5,020
Likes: 1,149
From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
I did my HB and seal at 74k along with relocating the OPS because they leaked. I didn't have to drop the sub frame to do those you just need to move the P/S rack over out of the way.
Like I said before clean it up and see were it actually leaks
Like I said before clean it up and see were it actually leaks
Melting Slicks
Joined: Apr 2021
Posts: 2,189
Likes: 82
Hey guys not to butt in i have the same problem the pan leaks from the oil pan gasket im almost sure. What oil dye additive and black light are you talking about that will show where oil is leaking from?
Does the dye harm the oil or have to be changed directly after or run the length of the oil change intervals?
You're saying its possible to leak from the oil pressure sensor?
Does the dye harm the oil or have to be changed directly after or run the length of the oil change intervals?
You're saying its possible to leak from the oil pressure sensor?
Last edited by Justin Raney; Mar 8, 2023 at 04:17 PM.
Melting Slicks
Joined: Nov 2014
Posts: 3,399
Likes: 1,339
From: Havre de Grace Maryland
Should I have a oil leak that has been confirmed that it is from an oil pan, before I spend thousands to fix, I would try putting in an oil stop leak product. I had a oil leak in my DD Murano that to replace the gasket, it was $2000 +. I put in Titan Oil Stop-Leak and it fixed it. Not cheap but under $100. No leaking for several years with oil changes.