Spinmonster

I have a Hummer H3 with the 4L60e and need to upgrade the trans for power. Is a new 4L70E a better move than a built 4L60E? The truck is AWD.

I'm not sure whats different with them case wise or internals. A new 4L70e looks to be cheaper than a built 60e.

Any recommendations on a trans builder if the built 60e is the way to go?

mrvedit

A 4L70E is a late model 4L60E with an Input Speed Sensor (ISS). I don't think it has the 4L65E parts such as 5-pinion planets and hardened input shaft because there is also a 4L75E. I suspect your H3 actually has a 4L65E; which would mean that a 4L70E would be weaker than what you have.

Assuming you would like a firmer shifting trans, get a well built 4L65E from sponsors FLT, RPM or Performabuilt.

What year is your H3?
Starting around 2008 significant changes were made which affect PCM/TCM compatibility.
In particular the 3-2 shift valve was deleted and the pressure manifold switch was replaced with a mechanical switch on the internal shift rod.

Spinmonster

I have a 2008 Alpha H3

RPM has a 4L65E which would be fine as long as it is going to actually work. Can a 4L60 be rebuilt as a 4L65 as far as internals. I wanted something that just swaps in.

mrvedit

Yes, a 4L60E and 4L65E are externally/electrically identical.
Just a tiny difference in the internals.

Be sure to talk to RPM so they know you have a 2008 and build it with the correct valve body.

Spinmonster

Thanks for all the info.

It appears the 4L65E was only used with trucks mated to a 6 liter. The 05 corvette has it too as does the 05-06 GTO.