My brother has had the same code on his 05 5.3 with a stock 4l60e. So the may just need to clean the filter? I might do that on his truck soon. I

The code always shows up when he's just cruising down the road.

 

I know this is a very old thread. But 06 sierra5.3 what fixed your truck?

my truck is doing the exact same thing.

 

Does yours have a harsh 1-2 shift??? P0894 is an updated p1870 and theres a bulletin on it about replacing the valve body..... I will see if i can find it tomorrow

 

4L60E GM Bulletin TSB # 01-07-30-023A DTC P1870 at trutechtrans.com

Found this, its an older version but result is the same ill find the updates version tomorrow...

 

thanks wolftrk99. I see your from va beach. I was stationed at Norfolk for about 7 years off and on. thanks for the help.

 

No problem.... ive been here for About 15 years now and if i could bear being that far away from my kids, id probably be somewhere else..like back in northern VA... Lol cant blame ya for not aticking around this area!!!

 

well wanted to give an update. I had a bad TQ converter that was causing my P0894 code.