1 Ton Tahoe

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Tonyrodz

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Cool, My late teens till mid 20’s I was Heavy Equipment Operating and Wrenching on the last bit of Oil/Gas Drilling operations in the Mackenzie Delta. I work rotation up their now. 10months of blistering winter, 1 month of summer.

Heres a photo of the ol Rickshaw form back in the day, 87 Pathfinder 35x15.5 TSL’s.

View attachment 374047
Sounds like my kind of weather.
 
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YukonandtheHOE

YukonandtheHOE

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To get back on track, are their any differences between the 2500 suburbans and the 1500 in the body hight on frame to speak of?
 

Ilikemtb999

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After owning so many 6l80/90 vehicles I think 4l80’s are way less quirky and a better driving trans. Even with tuning the 6l80 is a goofy trans.
 

hagar

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I have done a 2008 regular cab short box silverado exactly like you are talking. You will need the main engine harness since the 6l90 uses an internal tranny controller. You will also need to deal with the reduculous huge output shaft yoke on the 6l90e, it shocks everyone once they see what they have to deal with on thsat yoke. It all fits just fine though on a stock floor height, no body lift was used and it was for sure the taller 6l90, not a 6l80e.
I do see one problem you will have though, the years have to be matched between the tcm inside the trans and the year of the main engine pcm. 2007 to 2009 use one tcm to pair up with the 2007 to 2009 pcm, then in 2010 and up, you need a 2010 and up tcm. Another option could be to use the newer pcm in your truck, but I am not sure if that is possible.

You don't need the 6 speed cluster and shifter, it works just fine with the 4 speed stuff, you just can't select shift gears which is useless in performance driving anyways. A proper tranny tune, just throw it in drive, and let the vehicle shift.

When everything is hooked up properly there is no need for a segment swap. Since the pcm and tcm are independent of each other, they both read as their own modules. Once it's hooked up and you pull the tunes, it automatically shows as a 6l90 equipped vehicle, and your engine stuff is the exact same as when it was a 4 speed.
 

avalonandl

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To get back on track, are their any differences between the 2500 suburbans and the 1500 in the body hight on frame to speak of?
Yes , the 2500's (SUV) have deeper frames and a body lift of about 1.5 inch.

They are much heavier.

I had a 2004 Avalanche 2500 (same as a suburban) w/ 8.1 and 410's.

It had the 4L90. Thee 6 speed would not work diffent engine BCM etc- 24x vs 58x reluctor etc. I would have to wind the big block out to 5200 rpm to merge on the highway. I wanted the 6 speed...cat and avalanche (2).jpg
 
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YukonandtheHOE

YukonandtheHOE

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I have done a 2008 regular cab short box silverado exactly like you are talking. You will need the main engine harness since the 6l90 uses an internal tranny controller. You will also need to deal with the reduculous huge output shaft yoke on the 6l90e, it shocks everyone once they see what they have to deal with on thsat yoke. It all fits just fine though on a stock floor height, no body lift was used and it was for sure the taller 6l90, not a 6l80e.
I do see one problem you will have though, the years have to be matched between the tcm inside the trans and the year of the main engine pcm. 2007 to 2009 use one tcm to pair up with the 2007 to 2009 pcm, then in 2010 and up, you need a 2010 and up tcm. Another option could be to use the newer pcm in your truck, but I am not sure if that is possible.

You don't need the 6 speed cluster and shifter, it works just fine with the 4 speed stuff, you just can't select shift gears which is useless in performance driving anyways. A proper tranny tune, just throw it in drive, and let the vehicle shift.

When everything is hooked up properly there is no need for a segment swap. Since the pcm and tcm are independent of each other, they both read as their own modules. Once it's hooked up and you pull the tunes, it automatically shows as a 6l90 equipped vehicle, and your engine stuff is the exact same as when it was a 4 speed.
Yes I’ve done a similar swap Gmt800 sierra Short Bed but with a 5.3 in place of the 4.3 with a segment swap and butcher tuning.

It was already planned to bring everything related to the engine over from the Sierra. Now I’m thinking the BCM, Column and hopefully not the firewall/dash harness to get it all working. Or maybe its just as simple to unlock the Sierra E38 and tune out the VATS before I pull it, then plug it into the Tahoe and hit the key and see what happens.
 
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YukonandtheHOE

YukonandtheHOE

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Ok, in the thick of it now. Questions i need to ask. Should I swap the oil pan for the level sensor? I Have to use the 5.3 engine harness from the 07 but short of the starter trigger wire and the lack of AFM seem the only differences. The flex plate from what Ive read is a direct bolt over to the 6.0 for coupling the 4L65. The 6l90 is a no way because it would be comparable to a jeep YJ rear driveshaft haha shes a long unit!, weird to see it was only a 3 bolt converter though.
 

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