You guys use high mileage engine oil?

[Crazy Al]

Only ever used Mobile 1 after break in (or AMSoil in the bike), no matter the miles.

As for using high mileage oil and it curing the clicks and clacks, I was aware of nothing you could do to resolve the start up piston slap sound.

 

[Chads93GT]

On a side note, I got my tahoe 3 years ago with 100k miles on it, put 182k on it since, and its ALWAYS had the piston slap, its never gotten louder or quieter. Friends who have bought new silverado's with the 5.3 in them slapped from the factory. one had the engine rebuilt with less than 2k miles on it through gm, and even after the rebuild it had the slap. Its a design flaw, nothing more. Just be glad its not a catastrophic design flaw.

Have no fear, I beat my truck to death and its still going strong.

 

[Crazy Al]

I have a Jasper remanufactured engine in my truck, put about 2000 miles on it so far, still no slap. Nice not hearing it, but I'm still in the habit of letting the truck warm up for 30 seconds or so before pulling out, probably always will be, that noise sucks.

Same as Chads, everyone with a 5.3 I know has sounded like that, even from new, on cold start.

 

[TheFuzz]

Yep, my stepdad's 08 Silvy Z71 has a little slap. Nothing you can do to cure it; it's a design flaw in the pistons. When cold, the engines tick. This is due to excess play between the skirt of the piston and the cylinder wall. As the piston warms up to operating temperature, the skirt expands and the noise ceases. Just the nature of the beast.

More to the point, I rotate between Castrol GTX and Castrol GTX High Mileage every other oil change; the regular GTX has the additives to keep the excess sludge down, and the High Mileage keeps the seals nice and tight. No leaks or problems, I have 107K+ right now and it runs like a top.

When I drop in the cammed 6.0, I'll be running Royal Purple in it. Until then, dino oil is all my rig needs to be happy.

 

[YNOT]

just wondering, i read that high mileage oil has some conditioner in it along with seal sweller. i'm going to put some in next oil change.

i'm not worried about the cold start piston slap. my dad got a new engine warrantied after like 75,000 miles because of the slap.

---------- Post added at 05:36 PM ---------- Previous post was at 05:35 PM ----------

Replace all lubricants with Royal Purple.....Tranny, Crank Case, Differential......you'll be real glad you did

to late, i already did fluids in this thing.

 

[WickedGoat]

So far, knock on wood, neither the GTO nor the Yukon have piston slap. I just changed the Yukon over to Pennzoil Platinum 1000 miles ago and the GTO has gotten synthetic since 500 miles on the odo. MY '02 Grand Prix had piston slap, but it never caused any problems, just an annoying ticking sound that you just learn to get used to.

 

[Clemsonbloz]

think with yer dipstick jimmy

 

[nc6600]

I run amsoil in the 96 that has 230k on it.

 

[rdtahoe]

The Tahoe I bought has a tiny bit of the GM knock sometimes when I start it up cold and then it goes away pretty fast. It didn't knock at all the day I bought it. (go figure)

Should I be running high mileage oil in it since it has 105,000 on it? i've always just used valvoline 5w30 in my stuff.

My 2000 LT 5.3 had a slight piston slap and ticking that lasted for the first 30 seconds or so pretty much since I bought it new in '00. Now at 103K miles with it. Engine has always run well, just the same now as when it was brand new.

Used M1 since new with good filters (Purolator Pure 1's) since new, but I read an article a couple oil changes ago (every 4K miles or so since new) that 0W - 30 flows faster at startup and may help. I changed to that, and it did help.

If you run a syn oil now, give it a try at your next change (unless you have a problem with putting M1 in your truck). It might help.

 

[withac]

Replace all lubricants with Royal Purple.....Tranny, Crank Case, Differential......you'll be real glad you did

Agreed. Gets spendy to do them all but at least do the crank case.