wats up guys i have a 2003 4.8 ecsb silverado and the 4l60 is almost done for so i wanna switch it over to a 4l80 cuz ive been reading they r much stronger. if i do that will it mess the computer up at all or is 4l80 truly just a built version of the 4l60 and no difference in the computers mind.

 

The computer will have to be reflashed with 4l80e program.

 

oh and the 80e is a completely different animal from the 60e

 

thanx for the help guys any1 think a flt level 4 4l60 will hold up to a hopefully 400-500 hp 6.0 or should i just man up and spend the extra bills for a 4l80?

 

your best bet would be to call FLT in the morning and let them know your plans and they can make a recomendation off of that

 

I think a FLT level 4 will easily stand up to 400-500hp. The 80e has different gearing as well. It will feel like a different truck with the 80e in there.

 

well on the 80e will that be like lower gearing or do u think it will feel better or stronger with the 80e. i like the 4l60 shifting and stuff and wouldnt wanna lose the longer feeling gear ratios.my question is basicaly wats gunna feel different from the 80e to the 60e.

 

I did the conversion. The first gear in the 80e sucks! Most will say to go with the a looser converter or 4.10's, but comparing first gear to first gear, there is a huge difference. The first in the 80e takes off very slow. 60e has a 3.06 and the 80e has a 2.75.

That is the only bad thing I could think of and there are remedies for it. The 80e can do 60-65mph in first gear. The transition between the gears in much better than the 60e, and there is minimal rpm drop off between shifts.

The 80e is very strong and will hold up easily to 500 rwhp with a cooler and a shift kit. The conversion can get pricey depending on if you do the work and where you get the parts from.

 

Yea, the 1st gearin the 4L80e would be very slow with the 4.8 unless you are FI...

Personally on my 5.3L I run 1,600 RPM stall TC and 4.56 gears with 33inch tall tires. I find that while a little slow off the line, once I hit boost at around 25mph (which happens pretty fast) the truck screams and since the 1st and 2nd gears are long I get a huge amount of pull through the RPM range (the 4L60e would be into 3rd at the 3/4 through 2nd mark for the 4L80e)... In fact, if crusing at 60mph it will kick down to 2nd gear at WOT and i hit full boost instanly, its quite the ride! I am sure when i get the 6.6L in that 1st gear won't be any problem anymore... Oh sorry, i am rambling...8-)

 

I think the level 5 would be enough for you. It is more than a level 4, but the cost would be way less than switching to an 80e.