91’ suburban 6.0 ls swap

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Jsynobie

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Graham Washington
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Jason
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1991
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Suburban
Engine Size
350
Always wondered why my ac didn’t ever get cold well now I know why lol. Making some progress on my swap. I have a buddy stopping by tomorrow am to help pull the 350 out and start pulling the 6.0 apart. Waiting on my lsx motor plates to get here, they should be just in time to be installed.
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Jsynobie

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Jason
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1991
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Suburban
Engine Size
350
My mounting plates are here and it’s time to start pulling the 6.0 out of its old home and put it in its new home

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idahovette

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From past experience, that wrench is gonna slip into that bucket any second!!!!
 

Vbb199

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350, 502
Thank you for all the info I appreciate it. I was told when I bought my donor suburban it had a 4l80e in it but crawled under it yesterday and found out it has a 4l60e and 246 tc so I’m gonna swap everything back to the tc. My reasoning for doing the dash swap is to modernize my truck and not have the same old looking squarebody dash that everyone has. since I have the whole donor suburban why not give it a shot and see. if I don’t like it then back to the old dash.


Since it IS a 4l60e, you should be free and clear to use the suburbans Np241 :)

I think anyway, I cannot remember but at some point in time the output changed on them.

Is the adapter side that points to the transfer case 4 bolt?
 

Jsynobie

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Since it IS a 4l60e, you should be free and clear to use the suburbans Np241 :)

I think anyway, I cannot remember but at some point in time the output changed on them.

Is the adapter side that points to the transfer case 4 bolt?

the part that adapts to the transmission is 4 bolt and the side that bolts to the transfer case is 6 bolts.
 

Jsynobie

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1991
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Suburban
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350
So I did what everyone said I shouldn’t lol but it’s my ride and I’m gonna do what I want lol

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Jsynobie

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So I have a few questions for everyone about my swap. I didn’t think I would need a different oil pan but I do. I’m wondering what oil pan others have used to do this swap? Also wondering about headers as well. I thought it would all fit with cutting the frame and I’m not doing that I would rather spend some more money and not mess with my frame.
 

Bextreme04

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1980
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K25
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350-4bbl
So I have a few questions for everyone about my swap. I didn’t think I would need a different oil pan but I do. I’m wondering what oil pan others have used to do this swap? Also wondering about headers as well. I thought it would all fit with cutting the frame and I’m not doing that I would rather spend some more money and not mess with my frame.

I wouldn't cut the frame either. If it is just a little interference I'd just get out the extension and the hammer. Plenty of info out there that says "clearancing" the headers doesn't hurt performance at all. Alternatively, if you just have the stock manifolds, you can buy specific swap headers from several different places since these square body LS swaps have become so common.
 

Bextreme04

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heres a link to an LS oil pan guide with measurements and pics. https://www.lsenginediy.com/ls-swaps-oil-pan-guide/

Looks like the 2007-up truck pan is a good fit for all 1960 and up GM vehicles.

Those LSX mounts also have different mounting points for the clamshells... did you make sure that you don't just need to select a further forward/backward mounting location to clear the 6.0 pan?
 

Kelvin

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1991
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Suburban 2500
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5.3L
I guess I've just been lucky the whole process on mine, Oil pan fit, Stock manifolds fit. 4l80E was already in it. Sill doing the wiring but I should be ready to fire it up in a couple days. I see your battery tray is already on the drivers side. Bonus. I suggest you buy the diesel go pedal if your DBW.
 

RoryH19

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I guess I've just been lucky the whole process on mine, Oil pan fit, Stock manifolds fit. 4l80E was already in it. Sill doing the wiring but I should be ready to fire it up in a couple days. I see your battery tray is already on the drivers side. Bonus. I suggest you buy the diesel go pedal if your DBW.
The 6.5ltr diesel pedal from the 90s works great. Just swap 2 wires.
 

RoryH19

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Not sure why you are having issues with the swap. Maybe motor mounts?

I have a 6.0 with 4l65e and np241c transfer case in my k5. No cutting or clearancing required. I used the stock driveshafts. Also run shorty headers and full dual exhaust.
 

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