I just had to do an in frame on the engine exactly like this, the pistons are designed after it gets a few miles on it the Pistons will start slapping in the block and wearing the block down where you’ll have to get it bored and a new sleeve put in it it would be best to go ahead and replace it with aftermarket pistons. That’s a solid piston all the way down through the connecting rod, wrist pin so it doesn’t have a small area at the top of the piston that can shift and put unnecessary. Ware on the side of the block causing blow by in the engine to eventually start missing and throwing white smoke. Out the exhaust and out the blow by tube . The engine that we had to do in frame only got the one cylinder board with a new sleeve and all new pistons was put in the block as it was it only had 250,000 miles on it before the engine failed due to the design of the piston .
What was it doing before. My truck is surging and runs rough I get it on the street and runs rough for about 10 min at 50 then goes all the way down to about 10 and smokes blue white.. turn it off wait then it goes again for another 10 min all over again
