ZZ502 w/ 6L80 swap

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SeanV

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I'm sure that I'm the only one on the planet who has experienced that snowball effect sensation when it comes to your ideas and/or parts collection processes, so I'll explain how it happens. I planned to LS swap my '77 Suburban so I bought a running/driving 2005 Denali real cheap. After deciding no LS and to keep my 454, I got a .040 Gen V block ready to assemble. I took it to my favorite machine shop to survey its readiness where he offered me a deal on a ZZ502 crate engine from a project where the guy decided to LS swap his 70 Chevelle. Next I call a hot rodder friend and ask if he has any leads on a 4L80 tranny. He says no, but he does have a 6L80 and will take my Denali in trade for it.

So now I've got a 502 crate engine and a 6L80 I'd like to swap into my 1977 C20 Suburban. I've seen a few other threads a year or so old, but it seemed to be a information/fact collecting mission. No one was actually moving forward with that kind of swap. Well, now that we've finally got a TCM from the aftermarket, has anyone tried this swap?

For more information/fact finding help; is there any such thing as a high-hump transmission tunnel in the 2WD Suburbans? With the extra length compared to the TH400, is a one piece driveshaft conversion a possibility?
 

yevgenievich

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Manual equipped squares received a high hump floor.
 

SeanV

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That's good to know, thanks. I can order the high-hump tunnel for a manual transmission truck and not have go "custom" to get it to fit if the problem comes up.
 

Catbox

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Photo of the bolt in manual hump in my truck for visual reference.

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Waylon

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That's good to know, thanks. I can order the high-hump tunnel for a manual transmission truck and not have go "custom" to get it to fit if the problem comes up.

I believe all of the low hump automatic humps are not bolt in. They are part of the floor. And the hump where it meets the firewall is shaped differently. I don’t think it will be as easy as just bolting in a new hump. I know that’s the case with mid 60’s C10’s anyways.

I’m almost positive you’ll have to do some cutting and welding to put a high hump in there.
 

Camar068

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I'm sure that I'm the only one on the planet who has experienced that snowball effect sensation when it comes to your ideas and/or parts collection processes, so I'll explain how it happens. I planned to LS swap my '77 Suburban so I bought a running/driving 2005 Denali real cheap. After deciding no LS and to keep my 454, I got a .040 Gen V block ready to assemble. I took it to my favorite machine shop to survey its readiness where he offered me a deal on a ZZ502 crate engine from a project where the guy decided to LS swap his 70 Chevelle. Next I call a hot rodder friend and ask if he has any leads on a 4L80 tranny. He says no, but he does have a 6L80 and will take my Denali in trade for it.

So now I've got a 502 crate engine and a 6L80 I'd like to swap into my 1977 C20 Suburban. I've seen a few other threads a year or so old, but it seemed to be a information/fact collecting mission. No one was actually moving forward with that kind of swap. Well, now that we've finally got a TCM from the aftermarket, has anyone tried this swap?

For more information/fact finding help; is there any such thing as a high-hump transmission tunnel in the 2WD Suburbans? With the extra length compared to the TH400, is a one piece driveshaft conversion a possibility?

I've looked at the swap here and there. My 2005 LS won't control a 6L80 so it would require the controller that you already purchased. The project is too high for my liking. Also recently I've read that the 6L80 is not heavy duty like you think because it has "80" in the model. A lot of people are recommending the 6L90 over the 80. Worth looking into before you pull the trigger.

As for the hump, yes I believe your going to have to do some minor cutting to make it fit.
 

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