Buyin a Denali.. 6 speed trans?

Whats up Guys?

Im lookin to buy a new truck pretty soon (lookin into the Denali since it has the 6.2) and i am lookin to get it turboed sometime next year.. i know it will be 07+nnbs and i was wondering what everyone thinks about the 6 speed that is it in....

Basically is it a good trans? strong like a 4l80? is it faster since it is 6 speed? will it hold up to around 600hp maybe a lil over?

and by the way ive learned a good bit on this site in the short time i have been on it so just wanna say thanks to everyone especially NP.

ive got a 09' Sierra Denali..the 6spd is badass and fun manually tap shifting it.and yea it'll be faster than your average 4spd trucks....im not sure on how much hp they handle...should be around 5-600

I think Mitch(sprayedenali) had some issues while spraying on his 6.2 denali with the 6spd, but he may have been spraying though the shifts.

His issues were tune related.

Couldn't remember. Did he tune it himself?

Np tune, didn't work out then I think HESCO redid it if I remember right.

I thought his main issues were 02 related with the headers.

Just to recap, when he left here the tune was shifting fine, it wasn't until later when nitrous was installed that the shifts were holding too long.
unfortunately, with the 6speeds, they cannot be tuned remotely due to the controller being internal to the trans.

ya, he had some o2 related issues as well, that causes it to stumble and not run correctly, i've seen others post about this as well, picky o2 sensors.

so is the best idea to replace the 6l80e with the 4l80e? is there any difference except for one has 4 gears and other has 6?

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Originally Posted by farmtruc

Just to recap, when he left here the tune was shifting fine, it wasn't until later when nitrous was installed that the shifts were holding too long.
unfortunately, with the 6speeds, they cannot be tuned remotely due to the controller being internal to the trans.

ya, he had some o2 related issues as well, that causes it to stumble and not run correctly, i've seen others post about this as well, picky o2 sensors.

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All NNBS sensors are picky. My knock sensors have picked up KR for the last 8 months, even on a bone stock tune and 91 octane.