4L80e vs. 4L60e ???

99-2door · September 27, 2003

I am looking at a 96 2500HD to buy for the engine and trans for my 67 project. It has the 5.7L vortec and a 4L80e. I would like to find info on the 4L80e and how it compares to the 4L60e, such as gearing etc.... Is there any measurable power loss through a 4L80e instead of a 4L60e. It will be a 2wd 1/2ton shortwide. I am contemplating making a 383 out of the 5.7L, so maybe the heavier trans will be more desirable for future mods anyway. Our 96 c3500 7.4L has the 4L80e and I like the way it performs, and the 95 SRW K3500 we used to have had the TBI 5.7L and a 4L80e and it was nice too, seemed to have pretty much the same shift characteristics of the 4L60e. Any info you can steer me towards is appreciated.

Thanks,

Jason

BTW this truck won't be used for towing at all....maybe a jet-ski.

I've got the 3500s for the heavy stuff

Shaners · September 27, 2003

I think the heavier tranny is what you want especially if you are going to build a "stroker".

westex39 · September 27, 2003

Gearing for the 4L80E is:

First gear - 2.82

Second gear - 1.82

Third gear - 1.00

Overdrive - 0.75

4L60E is:

First gear - 3.06

Second gear - 1.62

Third gear - 1.00

Overdrive - 0.70

For your application I would use the 4L80E. This tranny is much stronger, and will tolerate the torque you going to have when doing all your mods.

Luck with your project

westex

99-2door · September 28, 2003

Thanks, the gears are what i was really wanting to know about. Does anybody know if there is a power loss through the heavier trans? I know the TH-400 had a pretty big power drop through it. Just trying to find out as much as I can before comitting to the HD trans.

Rotorwrench · September 28, 2003

You'll like the 4L80E alot more. It's much tougher and has better gear ratios. After driving a truck with a 4L80, a 4L60 truck feels like it falls flat on it's face when it shifts into second.