SUM-680500 truck flanges. I need a gasket that will fit one of the flanges. The walker 31718 fit one of the flanges but i cant figure out which one to get for the other one. On the listing on summits website it says the 116000 will work but it is too small. Anyone use these flanges? Which gaskets did you use?

 

@chrisv45,

We recommend the Remflex RFL-2070 manifold gaskets for the SUM-680500 truck exhaust manifold flanges. We want to work with you to get those coming your way. Feel free to PM us with your order info, and we'll be happy to assist you from there.

 

I went ahead and ordered them, thank you! Curious, are there any similar that can be bought at a parts store? Id hate for these to become unavailable in the future and not have a way to replace them. The walker gasket fit the one flange, wouldn't there be another walker gasket to fit the other?

 

@chrisv45,

That's good to hear.

As far as factory style replacement gaskets from Walker, the driver side is the WLK-31718. The passenger side uses a donut style gasket, which would be WLK-31554. We looked this up using a 2005 Silverado 1500 5.3 as the reference.

If you look at the Walker diagram below, the driver side shows a flat flange at the exhaust manifold to the converter inlet pipe. The passenger side shows a flange with a bell at the catalytic converter inlet pipe. That is why the WLK-31554 donut gasket is used on that side.

For the Remflex gaskets, it looks like they are available individually. RFL-2070A is the driver side gasket, and RFL-2070B is the passenger side. At this point, we're not seeing a direct substitute from another brand for the Remflex style passenger side gasket.

 

It sounds like a frustrating mix-and-match issue with the generic flanges. The key challenge with universal flanges like the Summit SUM-680500 pair is that they aren't always identical in their bolt patterns or dimensions, requiring two slightly different gaskets to seal properly.