Cold start rattle

[TTA 1077]

Any of you LS guys get a rattle at cold start? When the G8 sits for a few days and I start it, it seems to be pretty noisy for the first 2-3 minutes. Sound like lifters. First LS powered car so not sure if this is normal.

[PhillyD]

If this is a standard GM pushrod engine then you'll get that every day until the car warms up. GM engines are awesome performers but terrible in their lack of refinement.

[WS6]

Both my old 2005 silverado w/6.0 and the current GXp w/LS4 rattle like yours. I've seen technical service bulletins on it and if I remember it's not a lifter problem but rather a tensioner rattle.

[TTA 1077]

[quote=WS6;25245]Both my old 2005 silverado w/6.0 and the current GXp w/LS4 rattle like yours. I've seen technical service bulletins on it and if I remember it's not a lifter problem but rather a tensioner rattle.[/qu

Tensioner? Hmm! didn't think of that. It will go away though after warming up and only dose it after sitting for several days. I guess I'll have to look again next time I start it after a dormant period. It sounded like it was internal though.

[72firebird]

Originally Posted by WS6

Both my old 2005 silverado w/6.0 and the current GXp w/LS4 rattle like yours. I've seen technical service bulletins on it and if I remember it's not a lifter problem but rather a tensioner rattle.

LS series motors are notorious for piston slap on cold starts, especially the truck motors (and even more so the 6.0L, LQ9 I believe is the engine code). It's nothing to worry about, people have put 200k+ miles on vehicles with them sounding like that on cold starts since day one.

[WS6]

Yes, maybe that's what it was...I was thinking I read it was a timing chain tensioner noise.

[tta299]

My 02 8.1 rattles a little it has 257k miles my ls1 and ls2 dont. I use royal purple in them with wixx filters

[92conv]

Originally Posted by 72firebird

LS series motors are notorious for piston slap on cold starts, especially the truck motors (and even more so the 6.0L, LQ9 I believe is the engine code). It's nothing to worry about, people have put 200k+ miles on vehicles with them sounding like that on cold starts since day one.

That's exactly what it is, we had several cycle through the service dept when I was working at the dealership. As sad as it is, it's become acceptable for todays cars to have that noise on start-up. (We had a '99 Ford Expedition, that we purchased new, get bought back by Ford because of the very same thing. I was on my 4th motor when I finally had enough of it........so it's not just a GM thing either.)

I will tell you though, if it last longer than 2-3 minutes you may want them to look into it, or at least note that in your service records.......we had several 6.0 Denali's get new motors because the noise persisted beyond what is considered normal.

[tta299]

my 6.0 trailblazer has never rattled ?

[Quiky One]

My 5.3 does it, LS1 5.7 doesn't, and 6.0 doesnt.

5.3 was rattling when we bought it at 23k miles. Still does it at 80k!

[smiley]

i'd guess piston slap as well. google that and you'll find tons of info about it.

although neither of my ls1 cars have it..