Chevy & GMC Vans

Will the 4L80E Tranny bolt up to the 4.3 Vortec? Or alternately, will the transfer case behind that tranny bolt up to my 4L60E? I'm tired of my AWD single speed transfer case (always binds up the front end). Will the electronics work, or will it need a free standing computer? I ask because my Dad is taking parts from his K2500 to fix his Diesel Suburban, but doesn't need the driveline (I can modify driveshafts myself, done that before:



As you can see, I'm no virgin to fabrication!

Just don't know domestics all that much.

This was before the heavy mods!

The 4L80E will bolt right up to the 4.3. I know the 4L80E is longer so you would have to do some transmission mount work. I think the spline my be 32 instead of 27 so ad in drive line considerations front and back?.

The spline difference will also come into play when using the transfer case from the 4L80 to the 4L60. There are some on this site that know this info better than I.

Check this info out: http://www.manualtransmissionpart.com/T ... Model.html

They have one of the clearest exploded views of these transfer cases I have seen yet.

I don't know about whether a 4L80 will bolt to a 4.3. I do know the transfer case that bolts behind a 4L60 will not bolt to a 4L80. The 80 has a much bigger output shaft with 32 splines where a 60 has a 27 spline output shaft. I also believe the front half of the transfer cases are different as well as far as mounting pattern.

So I should be able to take the 4L80E with t-case attached, and with some mounting and driveshaft fabrication, mount it up then ? What about the tourque converter? I know the van has 1310 u-joints, and the K2500 has 1350 u-joints, but that's minor, as I can get a combo joint that has the 1350 on the driveshaft side, and the 1310 on the yoke side.

Your biggest issue is going to be wiring to the 4L80E and controlling it. The stock harness and PCM are not going to work. (I may be wrong on this though as it is my understanding)

Yeah, I was wondering about the electronics. Free doesn't always mean cheap! Or easy! May have to go the S-10 transfer case route.

99AstroMod wrote:Yeah, I was wondering about the electronics. Free doesn't always mean cheap! Or easy! May have to go the S-10 transfer case route.

If your daring, I found this: http://www.performancetrucks.net/forums ... ap-413157/