Oil Pan Gasket Change Out... what else?

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kalger

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I'm getting ready to change out the oil pan gasket (5.7L 350) on my 1975 GMC C1500. I'm looking for any tips/tricks to make the process easier and also suggestions on other things to do at the same time.

Thinking engine mounts, TH350 filter, and gasket change. What else should I look at doing while I'm under the car, have the covers off and the engine jacked up a bit?

Thanks!
 

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Rear main, timing set, timing cover seals/gaskets, valve cover gaskets
 

85 Squarebody76

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Definitely replace the oil pump while you got the pan off...
 

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Exactly what they ^ said if you’re planning on it runnin a bunch more miles.
 

fast 99

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Connector is a plastic union between the pump and the drive shaft. New ones come with a pump. They just tap on with a small hammer.

Get a one-piece pan gasket. Using an original style 4 piece is possible in the vehicle but is easier to screw up. Will also need to prime a new pump using Lubriplate or other heavy body lubricant. Gel sealer or silicone for main cap parting line and back of main seal. Need a torque wrench for rear main cap and oil pump if doing main seal.

Not suggesting Amazon, just easier to link.

 

bucket

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I'm gonna go the other way and say that a Chevy oil pump rarely fails. I only ever remember replacing one that had failed. That's it, just one single pump. On a '97 Express van.

Personally, I'd leave the pump alone. That's just another expense and a risk of unknowingly cracking the pickup tube or getting the depth set wrong. Imho, if it ain't broke, don't fix it.
 

Ricko1966

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I'm with bucket on this,it'll need rings and a valve job before it needs an oil pump he can do the pump then.
 

Ricko1966

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I'm with bucket on this,it'll need rings and a valve job before it needs an oil pump he can do the pump then. I also have only had 1 fail and I have no idea how many cars and sbc engines in my life. The one that failed was in an engine that was totally wore out needed bored,rings,bearings,crank everything.
 

Matt69olds

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Wow, this could get ugly with the MAW (Might As Well!).

If you’re going thru the trouble of replacing the oil pan gasket, I’d replace the timing chain if they’re is any significant wear. The biggest hassle with timing chain replacement is getting the timing cover around the oil pan. No oil pan, the timing cover falls into place.

Of course, to replace the timing chain, the water pump has yo come off. With my luck, the water pump would start to leak a month after reinstalling it!

How bad is the oil leak?
 

kalger

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Wow, this could get ugly with the MAW (Might As Well!).

If you’re going thru the trouble of replacing the oil pan gasket, I’d replace the timing chain if they’re is any significant wear. The biggest hassle with timing chain replacement is getting the timing cover around the oil pan. No oil pan, the timing cover falls into place.

Of course, to replace the timing chain, the water pump has yo come off. With my luck, the water pump would start to leak a month after reinstalling it!

How bad is the oil leak?
Not an insignificant oil leak(s). Now that I'm as far into it as I am, I'm also planning on replacing the water pump.

I am battling with the engine mount bolts—any tips/tricks there would be great. ;)

But yes, the "Might as well" factor is high... and increasing, as is the variety of tools in the arsenal.
 

Matt69olds

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Other than taking a little weight off the mounts, there isn’t much of a trick. They usually slide right out. What problems are you having?
 

kalger

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Other than taking a little weight off the mounts, there isn’t much of a trick. They usually slide right out. What problems are you having?
Big hands... small spaces. Additionally, just the age of everything is, I'm guessing, making the process of loosening the nuts a bit more challenging.
 

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