Lets talk about engine oil pan.

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BC K1500

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Yesterday I did a closer look to try to figure out the source of the leak.

The oil pan gasket looks fairly new, which doesn't mean much on itself. However, its possible that it was replaced not too long ago.
Most of the oil and grit is in front of the pan on the engine block area where the pan and the timing chain cover connects.

This leaves me whit a few possibilities;

1) Someone replaced the gasket not too long ago and did not properly seal the area between the timing chain cover and oil pan.
2) The timing chain cover seal is bad and its leaking there as well.
3) A combination of both.

I don't see any possible way to determine the condition of the timing chain cover without actually removing the pulley and harmonic balancer.

I'm thinking the most sensible thing to do would be to replace both the Timing chain cover and the pan gasket the same time.

What do you think?

Thanks.
 

Jobey

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It seems your on the right track. I’ve worked on a bunch of these trucks over the years and that’s a real common spot for it to leak. Could possibly just be the front seal behind the balancer as well. Won’t know till you take it off. I’ve had good luck without putting sealant on the neoprene oil pan gaskets but I might have just got lucky.
 
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Could you maybe remove the engine mount bolts and raise the engine up with a floor jack or bottle jack under the oil pan with a 2X4 4X4 or whatever is available - just anything to keep from poking a hole in the pan. Then, what if you put some blocks between the mounts and the pedestals on the crossmember and let the engine down on that so you can get the pan all the way out? Probably ought to check for things getting stretched and maybe clearance issues like the dizzy cap or something, oil sensor at top rear of block etc... Like Ive done about a kazillion trillion times on tons of vehicles..?? Is that not possible on this 1 particular truck right here?
 

alpinecrick

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You don't have to worry about removing them to change the pan gasket. There a millions of early trucks that don't have the braces. This is a GMT 400 thing
Under torque, the trans can/will crack without the braces—I’ve seen it. This was on a K1500. Think low range. GM didn’t go to all the trouble to design and include those braces for the sheer joy of it.
 

alpinecrick

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As I noted in the timing cover thread, pulling the pan is indeed a PIA.

I raise the engine, although it looks easier, dropping the the axle has its own challenges.

Remove those nefarious braces, unbolt the exhaust pipes from the manifolds, loosen the nearest exhaust hanger to drop the pipes down, remove the TQ cover, remove the oil filter adapter because there is one oil pan bolt hiding behind the adapter, unbolt the motor mount bolts, loosen the trans mount bolts.

I use two floor jacks with ~2 ft long 2x2’s to reach the mechanical fuel pump boss on passenger side, and the corner of the block on drivers side. Jack up the engine careful not to hit the firewall. Keep an eye on the distributor.

Now you’re ready to unbolt the pan…..

I bought a assorted set of silicone plugs from Amazon and they are one of the handier, cheap tools to keep fluids from dripping into my face and belly button from hoses and such.

Edited to add: 2x4 and 1x4 block between between each motor mount and frame fit perfectly and then lower and remove the jacks while working under the truck.
 
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1998_K1500_Sub

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Please share if you have any experience.

I had to drop my oil pan a few years ago.

After moving those NVH rods out of the way....

I had to remove the oil filter adapter (a right-angle adapter, might be unique to the 4x4, that positions the filter horizontally just above the front drive shaft). I saw no other option at the time, it interfered with the pan. The adapter came off relatively easily, but...

The difficulty was that the gasket between the adapter and the block tore when it was removed, with much of it remaining stuck tightly to the block. Removing that old gasket material was a PITA as it was old, tough, and very stuck-in-place. The location wasn't reachable with a putty knife or a box cutter, so I cut a piece of thin gauge sheet steel, bent it 90deg to reach up into that area, and sharpened one edge of it (akin to a putty knife), so I could use it to remove the gasket from the block.

Basically what I did was create a narrow "putty knife" that had a right-angle bend just before the edge. I wish I had some pictures b/c it would help explain just what I did and why.

Maybe someone else has a better solution regarding the adapter... maybe it doesn't need to be removed.

I needed a new gasket. The local dealer had one for me.
 
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Donald Mitchell

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I had to drop my oil pan a few years ago.

After moving those NVH rods out of the way....

I had to (well, "I did") remove the oil filter adapter (a right-angle adapter, might be unique to the 4x4, that positions the filter horizontally just above the front drive shaft). I saw no other option at the time, it interfered with the pan. The adapter came off relatively easily, but...

The difficulty was that the gasket between the adapter and the block tore when it was removed, with much of it remaining stuck tightly to the block. Removing that old gasket material was a PITA as it was old, tough, and very stuck-in-place. The location wasn't reachable with a putty knife or a box cutter, so I cut a piece of thin gauge sheet steel, bent it 90deg to reach up into that area and sharpened one edge (akin to a putty knife), and used it to remove the gasket from the block.

Basically what I did was create a narrow "putty knife" that had a right-angle bend just before the edge. I wish I had some pictures b/c it would help explain just what I did and why.

Maybe someone else has a better solution regarding the adapter.

I needed a new gasket. The local dealer had one for me.
Engine-uity!
 

alpinecrick

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I had to drop my oil pan a few years ago.

After moving those NVH rods out of the way....

I had to (well, "I did") remove the oil filter adapter (a right-angle adapter, might be unique to the 4x4, that positions the filter horizontally just above the front drive shaft). I saw no other option at the time, it interfered with the pan. The adapter came off relatively easily, but...

The difficulty was that the gasket between the adapter and the block tore when it was removed, with much of it remaining stuck tightly to the block. Removing that old gasket material was a PITA as it was old, tough, and very stuck-in-place. The location wasn't reachable with a putty knife or a box cutter, so I cut a piece of thin gauge sheet steel, bent it 90deg to reach up into that area, and sharpened one edge of it (akin to a putty knife), so I could use it to remove the gasket from the block.

Basically what I did was create a narrow "putty knife" that had a right-angle bend just before the edge. I wish I had some pictures b/c it would help explain just what I did and why.

Maybe someone else has a better solution regarding the adapter... maybe it doesn't need to be removed.

I needed a new gasket. The local dealer had one for me.
I’ve had to go through the same thing to scrape off the stuck gasket. I used the smallest Harbor Freight pry bar and sharpened the edge.

Do not try to reuse the O-ring either. The FelPro or AC Delco gasket kit is highly recommended.
 

eran tomer

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Under torque, the trans can/will crack without the braces—I’ve seen it. This was on a K1500. Think low range. GM didn’t go to all the trouble to design and include those braces for the sheer joy of it.
when i bought my k2500 those braces were missing. who knows how many miles it made without them.
 
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