I have a1999 chevy silverado with a 4.8 want to know if can go to a 5.3 with out changing any of the wire or computers
I do believe so, I was looking up parts to see if the same, and everything I looked at was the same for the 4.8 & 5.3. I know the OBDII computer has a good range for adjusting sensors. I am not seeing a problem.
You do need the 5.3 ecu. The harness will the the same. The ecu is not hard to change. It will come out with the motor and harness anyway. If you really can't get the 5.3 ecu just have yours flashed. However it should "run" with the 4.8 ecu but it will lean out a little.
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