Been looking for a newer NNBS daily driver for a while. I was originally looking for a 6 speed 5.3 but I have found great deals on a couple low mile 2012 4.8s.

anything to be aware of for a 2012 like tuning issues etc?

I know the 60 will self destruct, but how far have people taken the 6 speed in a heavy truck? (been following mike at New Era)

but If i'm going to need an 80 anyway....

also, trying to make myself stick to a 70mm plan, but I am open to suggestions from others who DD their turbo truck

 

5.3 6l80 made 498rwhp with a cam and T70 setup .

 

5.3 4l60e made 510rwhp stock cam, 60mm turbo S300 borgwarner

 

How much power are you trying to make?

 

500 sounds great for now, but you know how that goes.

Your truck is WELL over that for sure. What do you gauge as the reasonable limit for 6l80's?

 

any meth? what octane? dyno sheet? Great numbers, exactly what I'd like to do with my 5.3.

 

no meth, no secrets, just a GOOD turbo, borgwarner s300, its a 60mm, but it will blow away a MP70

 

500 rwhp with proper PCM/TCM calibration will last a long long time.

There are however a lot of variables to answering the question "Will a 6l80 hold up to this?". Torque/Horsepower output is obviously one of them, then there is vehicle weight, gearing, rim and tire weight, torque converter, (basically anything that effects load), engine powerband (how high of an rpm will it be shifted at) and what is it's purpose?

I have tuned a bunch of 800-900 flywheel hp RCSB trucks (some stock gears, some 3.73 gears, some 4.10 gears) with a stock 6l80, and have not had a failure yet, this is within the last 18 months anyway. All were about 5200-5400 lbs, and are raced frequently on the street (weekly). However, an 850 flywheel hp AWD Yukon Denali which is roughly 7000 lbs has had a freshen up (clutches) on the stock 6l80 once in this timeframe seeing the same driving conditions, but a 720 flywheel hp AWD Yukon Denali has not had any trans issues.

But you have to keep something in mind, when you are making a lot of power in a heavy truck (800+ flywheel hp) you have to understand that **** happens... And at that point anything is possible, but a 6l80e is a pretty cheap and simple transmission to just do a freshen up on (clutches) if something does happen.

My truck is currently 800 flywheel hp and the trans is fine, and I daily drive it and I race it, I am going to drive 10 hours next week, race it all weekend, and then drive back home with it. If it breaks, then it breaks, then we found what it can take. If it doesn't, then I will be doing the fuel system and 8 rib pulley set up which will put me at 20 psi (currently at 15 psi), and will continue to drive it and race it until it breaks, then we will know.

Please don't quote me on anything, I am just speaking based on my experience, there are many variables.

 

good info.

I am just toying with the 4.8/4l60 idea because you can pick up an almost new ecsb for under $20K.

I will probably hold out for a 5.3/6l80 if there is a good chance I won't hurt the tranny with 500whp and a little restraint.

 

500 hp is gonna be a fast truck regardless. There wont be much on the street that will be able to touch you. Ive been thru a couple 4l60s in my truck, but its also heavier.