[pala73]

I have a 1997 K1500 P/U with about 88,000 miles..it's got the 4L60E transmission..I've always had trouble with that stupid 1870 code, the trans ran fine, but it always threw the 1870 code..I replaced some of the solenoids the fluid & filter and it went away for a while..It came back so I replaced fluid again with a high mileage trans fluid. The code did not go away this time. I've heard that it may be a problem with a worn valve and valve bore. The strange thing is that the trans now slips when it is very cold out = 20 F or less. As soon as it warms up to the 30s or 40s, it runs fine. Anyone know what the heck is going on here? I'd appreciate any help or suggestions.