Hey guys, I've gota 99 Silverado 4x4 5.3l 1500, recently I had a transmission line rust through and I lost about 4-5 qts of fluid. After repairing the line and filling it back up I drove it for a few days all fine, but then as I was driving along around 55mph it slipped right out of 4th and started "flaring" as it tried to shift into 3rd. Diagnosis was 3-4 clutches must have been shot due to loss of so much fluid.

Transmission was removed and rebuilt in front of me (by someone who claims to have done this many times), he showed me the clutches which had been worn down to a very shiny smooth finish...obviously not good. So transmission was rebuilt with new clutches,frictions,seals,bands and all that good stuff. Not sure about the valve body, solenoids, or other components may be a reman VB.

Anyway, I finally got the transmission put in with my original Torque Converter (assumed to still be good), and at first i had sloppy shifts all the way around and no speedo, realized that I had one of the 3 plugs on the transfer case switched around. Now it has a firm 1-2 shift but flares again about 3-400rpm under light throttle before shifting into 3, and keeps revving without a shift into 4th without letting the engine rev above 3000rpms.

Had a Snap-On Tool plugged in and it recognized a.25 sec 1-2 shift and a 2.03 second 2-3 shift, I didn't see it recognizing any shortages or such but then again I'm not very proficient with the thing. This is basically the same problem I just had it taken out for. Is it possible there is another problem than some kind of assembly error with the 3-4 clutches?

Edit: The rebuilt transmission is not the same transmission removed from the truck.. meaning mine was surrendered as a core for the one that had already been rebuilt.
Edit II: Also there is a SES code for the EGR not quite sure of the specifics, not sure if this could have any affect on the trans... it wasn't on however when I took the transmission out.