Hello all. I'm looking for help in relation to a Cat D6R (4TR00811) 3306 engine, diff steer. When im tracking forward and try to steer at the same time it knocks itself into neutral and the transmission warning light goes off. It might do this 5 times out of ten. The transmission oil was just recently changed along with the filter. I've checked and changed the solinites on the modulating valve block, I've also gone throw the handbrake switch and the forward and reverse switch on the leaver. Any suggestions or help would be appreciated. Thanks.