Looking for some help. I swaped out my 5.3 out of my 2000 GMC 1500. I layed in a 6.0 out of a 2001 Chevy 2500. I used the 6.0 Wires and Computer. It runs and sonds great. BUT my tranny does not like it. It does not like to go back in to 1st gear and I it will not go in to D (4th). Should I go back to the 5.3 wires and computer. Or is there anyway I can make the tranny and the 6.0 computer get along?

 

Use the 5.3 PCM. The 6.0 uses the 4l80e tranny, which is different than the 60e. You should get LS1EDIT and use a 6.0 file to get the tables from to put in the 5.3 computer.

 

You need programming for your PCM to communicate with the 4l60e.Contact Speartech about getting the PCM programming although you would be better off in the long run to use the 4l80e that came with the 6.0 it's a much stronger transmission.Also did your 6.0 have a thicker flange on the rear of the crank if so you might have a problem with the spacing to align your torque converter.

 

whitt1 the flange from the 6.0 and the 5.3 are the same.
How would I contact Speartech

 

Flyer, how can I get my hands on a LS1EDIT.
I am going to swap out the Wires and Computer tonight.
But it sound like I am going to need to get this LS1EDIT to make some adjustments.

 

Speartech is a site sponsor just look to the right and click on the Speartech icon.LS1 Edit is available from www.carputing.com

 

I think the truck will run with the 5.3 computer OK.

Whitt made a good point .. you would be better off if you had the 80e tranny in there since it is much stronger.

 

The reason I asked about the flange is that early 6.0 engines came with the thicker flange while later model 6.0s mated to 4l80e transmissions use a spacer.6.0s used with 4l65es don't need the spacer.

 

If he has a 2K1 6.0 with alloy heads then he will be ok with the crank flange,had he had the wrong crank he would have not been able to bolt the trans up tight to the motor.You need to not drive it with the 4L80e PCM,run the 5.3 PCM until you get the tuning worked out,it wont run as well do to knock retard and TQ management & tuning being off but it may save your trans.

 

OK, I changed the wire harnes and I am back on the 5.3 computer. Does anyone know of any one in the LA,San Bernardino county area that could help with the modes. The idel is a little low