Will it shift into those gears if you manually move the lever and only not shift up if left in drive or will it still not shift either way?
If it will shift manually into those gears but not while in drive it is likely a wiring issue or a failed solenoid pack in the transmission. If it will not shift manually then it is likely that there are broken seals internally that are bypassing fluid so it will not shift into the higher gears.
I would check fuses FL-3 and C-14 in the dash fuse box as C-14 powers the transmission control module and FL-3 powers the control relay.
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Monday, August 20th, 2018 AT 10:27 AM