So for a couple months now my transmission has been acting up, it shifts up to 3 but no 4th or overdrive so I cant drive at high speeds, once it gets to 3rd its stays there kinda like in limp mode, it wont downshift or shift up just stays in 3rd , I got codes for every single solenoid in the transmission and seeing as it was rebuilt 3 years ago and driven less than 10k miles since I doubt it's the transmission itself the shop owner of the place that put my new one in said the same, I also have a front wheel speed sensor code and a 02 sensor code as well, I've checked fuses they all have power to the fuse, the neutral safety switch connector did seem like it was melted at one contact so I replaced it seeing pretty much all gm vehicles at the junkyard with the same problem(corroded connector on nss) I thought maybe that was the problem but no fix, should I change the neutral safety switch too? Since the old connector had a bad corner would it be bad on the switch as well? It was changed after the transmission already which is why I dont see how it even had a bad connector, any other ideas as to what could be causing the problem? Read somewhere that the wheel speed sensor could affect it but others say its unrelated,

 

You forgot to post the codes?

 

P0758
P0135
P0332
P0740
P0785
P1860
C0040
these were all the codes originally, after putting a new connector It did go down too p0757 p0758 p0332 c0040 and p0135

 

Involved in a flood?

 

Not a flood, but some mudding yes

 

Now that I remember the truck had a leak on the drivers side, do you think maybe the pcm could've been affected, the carpet ends up wet when it rains really hard, I think I fixed the problem but will have to wait till it rains to see

 

Possible? Start with the easy stuff first:
PIP5094

Check wiring/connector to RF WSS

C0040
Possible Causes
Faulty Right Front Wheel Speed Sensor
Right Front Wheel Speed Sensor harness is open or shorted
Right Front Wheel Speed Sensor circuit poor electrical connection

Check wiring/connector to the transmission

Make:HUMMERCode:P0758Definition:A/T 2-3 Shift Solenoid Circuit Malfunction (4L60-E, 4L65-E)Description:Engine started, engine speed over 450 rpm for 5 seconds, system voltage over 10.0v, and the PCM detected an unexpected voltage condition on the 2-3 Shift Solenoid control circuit for 5 seconds.Cause:

• 2-3 shift solenoid control circuit is open or shorted to ground
• 2-3 shift solenoid control circuit is shorted to system power
• 2-3 shift solenoid power circuit is open (test the TRANS fuse)
• 2-3 shift solenoid is damaged or has failed

KS too:
Make:HUMMERCode:P0332Definition:Knock Sensor (KS) Circuit Low Voltage Bank 2Description:P0327, P0328, P0332, and P0333 The engine coolant temperature (ECT) is warmer than -40°C (-40°F). The engine run time is at least 2 s. DTCs P0327, P0328, P0332, and P0333 run continuously when the above conditions are met.Cause:

• P0327, P0328, P0332, and P0333
• The KS signal circuits are shorted to voltage or ground.
• The above conditions exist for greater than 5 s.

HO2S:

Make:HUMMERCode:P0135Definition:HO2S-11 (Bank 1 Sensor 1) Heater Circuit MalfunctionDescriptionTC P0101-P0103, P0106-P0108, P0112, P0113, P0116-P0118, P0120, P0200, P0220, P0300, P0442, P0446, P0452, P0453, P0455, P0496, P1125, P1258, P1514, P1515, P1516, P1518, P2108 and P2135 not set, engine runtime over 120 seconds, engine speed at 500-3000 rpmCause:

• HO2S heater low control circuit is open or shorted to ground
• HO2S heater circuit is open or it is shorted to ground
• HO2S heater power circuit is open (test O2A fuse in fuse block)
• HO2S heater element is damaged or has failed
• PCM has failed