5.2 magnum swap--which gasket do I need?

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moparman9

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I am planning a 5.2 magnum swap. To install the 360 car pan on my 5.2 magnum, do I need the 5.2 magnum gasket or the 5.9 magnum gasket? I thought the all the magnum pan gaskets were the same, but there are different part numbers for the gaskets....
 
The 5.2 and 5.9 are the same gasket, wherever you're searching for this gasket has the wrong info. Just so you know, the LA oil pan gasket will work also.
 
The 5.2 and 5.9 are the same gasket, wherever you're searching for this gasket has the wrong info. Just so you know, the LA oil pan gasket will work also.
I thought that might be the case, so I went straight to the FEL-PRO catalog, and sure enough they are different parts numbers...
upload_2017-4-23_21-44-44.png
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They differ. Just like the older 360 cu in, the 5.9L has a larger rear hump, so different oil pan and gasket than the 340, 318 (5.2L), and 273 cu in engines.
 
If you are putting an LA pan on a magnum, you need an LA 360 gasket, unless you want a leak. The pans on magnums are all the same, 5.2 or 5.9. The gaskets are different, my guess it was to use one pan on both 5.2 and 5.9.
 
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gtsdude,
Thanks for clearing up. I was wrong. Rockauto shows the same PN for the oil pans. That means the oil pan would have a big gap on a 5.2L at the rear, so they designed a special gasket w/ thicker rubber at the rear for the 5.2L to make up the difference (photo). Seems unwise for long-term, especially as engines age and build-up crankcase pressure (worn rings), giving risk that thick rubber could blow out. I understand an oil pan from a 273/318/340 engine fits the 5.2L block, and would have the normal thickness gasket at the rear. Indeed, you want a 273 pan for an early A since it has a bump-in for the steering travel.

Speaking of poor gasket design, you all probably know of the problem w/ the gasket on the lower sheet-metal of the "beer-keg" intake blowing out to give a vacuum leak and oil suckage into the intake. People sell thicker aluminum plates to cure that.

5.2L gasket.jpg
 
So the 273-340LA pan will fit the magnum 5.2? I assume one could use the magnum 5.9 gasket? Does any one have personal experience with this in their car? I only want to install the pan one time (and only buy one pan).
 
Yes, the 273-340 pan will fit (people say, I have never done so), as will the associated gasket.

No, the 5.9L gasket will not fit. It fits only the 360 (and 5.9L) pan, which is different.

You didn't ask, but we must infer that a 5.2/5.9L pan will fit a 360 LA block.
 
I appreciate everyone's input, but it would make me more confident if someone who actually has a magnum 5.2 in their a-body would chime in and say if the LA pan is the one to use for sure.
 
iv'e got an 01 5.2 magnum in my 72 dart. you need an la 360 pan for the 5.2. i used an la 360 gasket on mine, but have read that you can get the magnum gasket to work also. dave.
 
This is confusing as hell. I was told the magnum 5.2/ 5.9 ARE THE SAME pan
 
You are correct, pans are the same on magnums, gaskets are not. The 5.2 magnum has the bigger rear main just like the 5.9 magnum, for what ever the reason the gaskets are not the same, still not sure the difference but I know its not because it has the LA 5.2 style rear main. So a 273, 318, 340 pan will not fit either magnum.
 
Found this on another site,
"A 5.2 Magnum pan gasket is basically the same as a 5.9 Magnum pan gasket. They are a different part number but it is really hard to see the difference. Basically just two little nubs where the rear seal meets the rails. Not even sure why they bothered creating a second part number."
 
iv'e got an 01 5.2 magnum in my 72 dart. you need an la 360 pan for the 5.2. i used an la 360 gasket on mine, but have read that you can get the magnum gasket to work also. dave.
Thanks, that is what I was looking for. Now the pan issue is settled. Maybe someone will post that has used the magnum gasket on the 5.2 and give us the final word on that.
 
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