1996 tranny crazy

my 1996 yukon sometimes or almost always slips out of reverse the first time i put it in gear, but if i go to p or n then back to rev its okay fot this time but it does it again after that. drive gears are okay, any ideas

my 1996 yukon sometimes or almost always slips out of reverse the first time i put it in gear, but if i go to p or n then back to rev its okay fot this time but it does it again after that. drive gears are okay, any ideas

When the 4L60E is put in Reverse, the lo-reverse clutch is applied and the reverse input clutch is applied. A problem with either of these clutches could be a fluid pressure issue or worn clutches.

You can test the lo-reverse clutch by putting the tranny in 1st gear and get the speed upto around 30 and let off the throttle. If the lo-reverse clutches are good, the engine should brake hard the truck should slow down quickly. If it feels like neutral, the lo-reverse clutches are gone and a rebuild is necessary.

Other possibilities are:
worn/cracked piston seal (lo-reverse or reverse input)
sticking lo-overrun valve
reverse input clutches
valve body
sun shell (when it goes, no 2nd, 4th or Reverse)

//2000CAYukon