Done with conversion, but now major tranmission problems!

[Bellflower]

Ok, I put an 02 model 5.3 in my 1996 C1500, we kept the 1996 4l60e. I used a nelson harness and computer. Trans shifted fine behind old motor and computer, but now with the 5.3 and nelson computer, its having problems.

-when first started up, truck starts in 1st and shift normal up till 3rd, then it is pretty much stuck in 3rd, will not down shift when slowing down or stopping or go into overdrive when crusing. after a few minutes, the truck will skip and buck a few times (like its being shut off) and then the trans goes to neutral (no forward or reverse gears) untill you shut it off for 10 seconds and start it back up, then it starts over again.

-has a code for 3-2 shift solenoid
-when scanned, all gear solenoids can be commanded, pressure is at 90% all the time and computer always thinks trans is in D4.

Im lost, Nelson says the tunes for the early 4l60's and the newer are the same. they asked me to post on here and see what I find. Thanks

[Botlfed]

So it has a code for the solenoid? Replace the solenoid.

[slow600]

I'm prob no help but my trans always says d4 as well, I have a 94 4l60 in my swap. It is strange it had no issues before swap.

[Bellflower]

someone said they may be one pin different, im gonna review my pinout and see if i missed something

[farmtruc]

Thanks for posting, to stir up some ideas, i'll repeat what i mentioned in my emial. the 3-2 solenoid is different or something along those lines.
I don't have access to older pinouts so i cant help there.
once that pin is figured out, it has to work.

the only thing on the tuning side is for me to max out the tcc pressure, since the older stuff is on or off, not like the new stuff which is modulated.

i emailed the owner of the truck we built a harness for that made it work.

[Tarinitup1]

Why not bite the bullet and get a good new trans in there.

[Bellflower]

here is the connector view off of alldata for the 1996 model 4l60 in my truck. does this help?

[Bellflower]

Why not bite the bullet and get a good new trans in there.

Other than being broke, paying for a wedding in march and a 1989 c1500 with a 565ci big block that eats every dime i have left over, buying a new trans wouldnt be a problem. lol

[PitchBlackC3]

Thanks for posting, to stir up some ideas, i'll repeat what i mentioned in my emial. the 3-2 solenoid is different or something along those lines.
I don't have access to older pinouts so i cant help there.
once that pin is figured out, it has to work.

the only thing on the tuning side is for me to max out the tcc pressure, since the older stuff is on or off, not like the new stuff which is modulated.

i emailed the owner of the truck we built a harness for that made it work.

I thought 96-up were all modulated.

[farmtruc]

If that's the case then the PCM and harness aren't an issue.