I have an 06 Silverado with a 5.3 that has a bad lifter, I replaced the lifters about 75-80k miles ago and one of them has gone out again. I have tried putting various additives in the oil to try to get it to function without hammering but have had no luck, I even tried putting Marvels Mystery Oil in the cavity and letting it sit there for a few days. I did verify good and steady oil pressure with mechanical gauges at both the oil cooler adapter and pressure sensor locations so it does not appear to be oil aeration problem, I didn't suspect that anyway because I changed the pickup tube oring about 50k ago. I am requesting suggestions for better lifters, I think lifters should last longer than this and with all of the work it takes to replace them I would like to not have to not do this again. Any recommendations would be appreciated.

 

Is it the same one(s)?

 

No it is not, the first time I had a lifter failure it was cylinder 5, I don't remember if it was intake or exhaust but the failure was intermittent. This one is # 3 intake and it really does not start making noise until the engine is between 1500-2k RPM but is always there. I have verified it is this one by using stethoscope placed on the rocker arms and can literally feel the lifter hammer. I don't suspect a flat cam lobe either as I can turn the crank by hand(breaker bar & socket)and the rocker arm seems to raise and lower smoothly but I wont be able to verify this until I get it torn down. I have not been driving it because I don't want to damage the cam. When number 5 failed I continued to drive it because the failure was intermittent and I ended up doing a little damage to the lobe. The other difference I notice in this failure compared to the other one that when I am stopped and I rev up the engine in the range where you hear the lifter I can also feel a vibration in the seat that correlates to the Knock. Some of you might be thinking this is a rod knock but it really doesn't sound like a rod and I placed the scope on the oil pan and didn't really hear anything that correlated to what I am hearing.

 

I ordered new lifters from EBAY(yes I know a mistake) that in the description indicated they were OEM and the picture showed lifters with ACDelco boxes with the lifters in bags that had the GM part number for each lifter. What I received was not what was shown an I am now trying to determine if what I received is a GM updated design or if I received counterfeit parts. The first picture is what my lifters look like and the second is what I received. Any information on these lifters would greatly be appreciated.