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Leaking pan, but what is it?

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Old Jun 3, 2021 | 08:47 PM
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Default Leaking pan, but what is it?

What is this pan for, and why is it leaking? Bad gasket?

It's in the rear, to the driver's side of the differential
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Old Jun 3, 2021 | 09:27 PM
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Im thinking the ABS unit may be located there, someone that knows for sure should answer soon.
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Old Jun 3, 2021 | 09:34 PM
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Yes the ABS is above, you can access it through the storage hatch it may be screwed shut with 7mm head once open you can start your inspection for possible problems


Looking at the picture I would give a look the Differental, you're pinion & 1/2 shafts looks like it's leaking. Sniff test the staining on box might be Differental grease

Last edited by s carter; Jun 3, 2021 at 09:41 PM.
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Old Jun 3, 2021 | 10:35 PM
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Originally Posted by s carter
Looking at the picture I would give a look the Differental, you're pinion & 1/2 shafts looks like it's leaking. Sniff test the staining on box might be Differental grease
I just changed diff fluid today. I did notice some fluid that seemed to be coming from *above* the diff. Maybe the top side of the cover plate is leaking, but I don't think I would know until I remove the suspension to access that diff cover... I'll have to look up what a pinion and 1/2 shaft are, but once I figure that out I'll report back. I still have some diff fluid, so I'll compare smells. I'll also inspect the ABS, since it seems that the pan must be the bottom of the ABS compartments, right? Thanks so much for the help!

Also, when I opened the filler plug on the diff, a small amount of fluid dribbled out, so it wasn't low on fluid right?

Thats the side of the diff, the fill plug on the left. There was fluid in the outline areas

There was a lot of fluid below the diff

Below the diff
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Old Jun 3, 2021 | 10:43 PM
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1/2 shafts and 1/2 shaft seals the small drive shafts that go to each wheel.

Pinion what the main drive shaft turns going into diff.

Last edited by s carter; Jun 3, 2021 at 11:11 PM.
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Old Jun 3, 2021 | 11:34 PM
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Uh, the rear diff was modified to turn the bottom-middle cover bolt into a drain plug?
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Old Jun 3, 2021 | 11:37 PM
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Originally Posted by Nomake Wan
Uh, the rear diff was modified to turn the bottom-middle cover bolt into a drain plug?

possible? It would only take 1 or 2 careful minutes with a drill to cut out the back of the bolt hole.
But I think the bolt is MIA.

Last edited by s carter; Jun 3, 2021 at 11:40 PM.
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Old Jun 4, 2021 | 12:53 AM
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Originally Posted by ihatebarkingdogs
What part of the car is the jackstand placed under?
They're under the halfshafts as you are thinking they are. They look like safety only since the jack is under the correct jacking point.

Regardless though, barkingdogs is right. Recommend that you don't place the jackstands under those halfshafts; they are aluminum and rather thin-walled. Even if they are only safety jackstands, if the hydraulic jacks on the side slip down a little the halfshafts will carry that load and deform if it's any significant weight.

Good luck with the leak detect and fix!
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Old Jun 4, 2021 | 07:22 AM
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The only fluid in the abs is brake fluid, so if it is leaking you would be low on brake fluid. Most likely the fluid is coming from the front of the car and streaming back on to the abs compartment.

Last edited by eutu1984; Jun 4, 2021 at 11:15 AM. Reason: fix fat fingers
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Old Jun 4, 2021 | 09:09 AM
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Originally Posted by eutu1984
The only fluid in the abs is brake fluid, so it is leaking you would be low brake fluid. Most likely the fluid is coming from the front of the car and streaming back on to the abs compartment.
I'll get the compartment open and take a peek anyway, but I did the brakes last month and was not leaking any fluid. Something near the diff is leaky for sure, you saw the exhaust pics, they were covered. And above the diff was dirty too
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Old Jun 4, 2021 | 09:15 AM
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Originally Posted by s carter
possible? It would only take 1 or 2 careful minutes with a drill to cut out the back of the bolt hole.
But I think the bolt is MIA.
I really thought that would be the drain plug but no. I replaced the screw, but listen. There was still a small amount of fluid in the hole. Could be that cover plate is leaking... could be leaking more so on the top, which would explain why it would be dirty above the diff
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Old Jun 4, 2021 | 09:19 AM
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I placed my jack stands like so. What is a better spot for the rear?

Front

Rear

thanks for pointing out that these are aluminum and thin walled

Last edited by Socalsalas; Jun 4, 2021 at 09:20 AM.
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Old Jun 4, 2021 | 09:36 AM
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Originally Posted by Socalsalas
I really thought that would be the drain plug but no. I replaced the screw, but listen. There was still a small amount of fluid in the hole. Could be that cover plate is leaking... could be leaking more so on the top, which would explain why it would be dirty above the diff
Yeah nah, the Dana 36 and Dana 44 on the Corvette do not have drain plugs from the factory. There are several ways to modify them to add one. For example: https://www.corvettecentral.com/84-9...-kit-nd-584029

Originally Posted by Socalsalas
I placed my jack stands like so. What is a better spot for the rear?
For the rear, how about the inside of the lower control arm where it meets the diff?
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Old Jun 4, 2021 | 10:52 AM
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I would look into replacing the differential vent. My D44 in my 84 leaked pretty badly when I bought it. I tried cleaning the vent a couple times and the leaking was reduced a little bit but still significant. I then found a new differential vent for a Jeep/Dodge at the local auto parts store. Wasn't an exact fit but works. Once I installed the new one it quit leaking. There is still some marginal moisture back there but it hasn't put a drop on the garage floor in a couple of years now. Cost of the replacement was around $5.
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Old Jun 4, 2021 | 11:33 AM
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Originally Posted by ihatebarkingdogs
Safety First. The further outboard, the more stable the car is on the stands. How about under the pinch welds at the indicated jacking points?
I didn't do that because the pinch welds are too close to the body for anything other than the jack that came with the car.

I just ordered so jack pucks cuz my pinch welds are looking ragged. Those might fit over the body and the weld. But it would require 2 floor Jacks. Which I totally could do, just lmk what the safest thing to do is. It's a big fear to die under a falling car, no thank you


Last edited by Socalsalas; Jun 4, 2021 at 11:36 AM.
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Old Jun 4, 2021 | 11:35 AM
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Ouch, looks like someone already tried lifting the car from the floor there too...
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Old Jun 4, 2021 | 11:39 AM
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Originally Posted by Nomake Wan
Ouch, looks like someone already tried lifting the car from the floor there too...
Yeah exactly, I'm finding out the previous owner treated this car like a beater. There's some damage from the car bottoming out, pinch welds bent to **** at all the jack points, obvs never changed diff fluid, probably not trans either it's gonna be a happy car when I'm through though. Even if I have to replace the entire diff, clutch, trans assembly dammit lol

Last edited by Socalsalas; Jun 11, 2021 at 11:16 AM.
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Old Jun 4, 2021 | 12:00 PM
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Usable jackstand points shown here:
https://www.corvetteforum.com/forums...jack-a-c4.html
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Old Jun 4, 2021 | 01:47 PM
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Originally Posted by kael
Usable jackstand points shown here:
https://www.corvetteforum.com/forums...jack-a-c4.html
super helpful, thank you
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Old Jun 4, 2021 | 07:39 PM
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Originally Posted by Socalsalas
I placed my jack stands like so. What is a better spot for the rear?

Front

Rear

thanks for pointing out that these are aluminum and thin walled
I would never use the halfshaft to support the weight of the car, that is just begging for premature u-joint failure. Suspension components are OK, but as mentioned previously, the frame (as far outboard as possible) is the best location.
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