Hello all!

Some of the incandescent bulbs in my gauge cluster burned out so I swapped them for LEDs from Tachtronics. Soldering went well and installation was easy. However, now the Suburban shifts oddly. If I accelerate slowly, I notice little difference, but when accelerating out of a corner, the Suburban can't decide what gear it should be in and won't shift up until about 5K RPM. The same thing happens when I floor it. It revs high and gets all confused again. Any thoughts? All the gauges work. No check engine light. 2004 Suburban 1500 4X4. (edit: I took out the gauge cluster and drove it. Same problem. Won't shift into 3rd or 4th. So, it's just a coincidence. With that said, I have found other forums that say try swap the shift solenoids, flush the tranny or rebuild it. Most have said that the first two options only worked marginally but didn't fix it entirely. Thoughts?)