code 1870 - trans component slipping I have a 1996 chevy suburban 1500 4x4 auto trans with overdrive. I just rebuilt the motor and it seems to be running fine now. But, tonight as I was test driving I was going up slight hill and pushed down on the pedal slightly and the engine rpm's jumped up and the CEL came on with code 1870 - trans component slipping. I put a new tranny filter and replaced the fluids when I redid the engine. I dont think it is low on fluid. Does anyone have any thoughts on what could cause this? there are 270,000 miles on the tranny. Your help is appreciated. Thanks JJ ---------- Post added at 08:56 PM ---------- Previous post was at 08:54 PM ---------- Also. THis has the 5.7 liter vortec motor.