List of LS problems. KISS
 

K.I.S.S. folks

Problems with the stock 4.8/ 5.3/ 6.0 engines. From '99-2015 truck owners and engine swappers. Not modified engines that end up with NX "speed hole in piston" problems.

Keep It Simple Stupid :D


Cause people like me, who only have an LS in their C10, wants to make sure he gets all the miles I can.



EX: My 4.3 s10 had injector problems and that's about it, everything else has fallen apart around it. Currently at 155k. My LS and trans came to me with 88k.

Re: List of LS problems. KISS
 

Exhaust manifold bolt heads break off

Re: List of LS problems. KISS
 

FWIW, I actually haven't had one blow a speed hole in a piston from Nitrous.

Early aluminum motors had metalurgy issues (98ish LS headgasket issues). Wrist pin noise in early motors. Between 01-03 there were some engines with rod bolt issues at higher rpm's (supposedly solved by mid 03), some had issues some did not, primarily occurs with RPM.

Plastic intakes get cracked when mishandled by wrecker or installer. Injectors stick when sitting too long.

4l60es break if you sneeze too hard.

Re: List of LS problems. KISS
 

:lol:

Re: List of LS problems. KISS
 

There's the piston slap issue, my 5.3 seems to have it on cold start, let it run for a few minutes and the noise goes away.

The ever popular exhaust manifold bolt issue. The OEM bolts "wear out" over time and break. GM also put Loctite on the threads so the best way to get them out is to weld nuts to the broken stubs and they come right out. I sold a 4.8L to a friend recently and all the bolts broke, I felt really bad but he was able to remove all of them using the welding method.

Re: List of LS problems. KISS
 

Some of the "problems" like the piston slap are really just annoyances. I've never seen one come unglued due to cold start piston rattle.

The LS is largely a VERY solid and VERY reliable platform, especially if kept stock(ish).

When you're gonna start leaning on them, spinning them hard, adding boost, etc, there's a few things to address depending on the year of your engine (timing chains, lifters, valve springs, pushrods, head gaskets, etc). For a driver, you generally don't need to worry about that stuff.

Re: List of LS problems. KISS
 

Oil pump o-rings in the mid 2000's.

Re: List of LS problems. KISS
 

Good stuff, folks. My 5.3 is an '05 with 4L65. So hopefully some of those issues were taken care of. Its just a stock DD.

I heard something about water pumps failing prematurely? When I dropped it in I replaced intake and valve cover gaskets, as well as the O-rings around the intake area. The pan was changed so the pick up got a new seal.

What is the oil pump O ring thing?

Re: List of LS problems. KISS
 

The engine itself of an LS swap will last for decades.

The rest of the build quality is where it counts. Fuel system, hoses rubbing, wiring quality, well made grounds, etc. Alternator failures seem common if you don't have the PCM controlling it, which the stock one does. Aftermarket ECUs need the 470 ohm resistor.

Otherwise, the short block would be about the last concern I'd have with the build.

Re: List of LS problems. KISS
 

Sounds like you got your bases mostly covered. The o-ring that qwik mentioned is the oil pump pickup seal (o-ring) that is at the connection of the pickup and oil pump just behind the timing cover...which is sounds like you already replaced.

Re: List of LS problems. KISS
 

The LS engines are known to consume oil. The main way that this seems to happen is by oil being sucked up through the PCV into the intake as the PCV system was poorly designed. I have a '06 5.3L L33 that was caked with oil inside the truck intake manifold when I took it off. You may want to consider running a catch can, or switch to the LS6 valley cover for extra assurance.

Also, before you put the engine in the truck, you may want to consider replacing the rear main seal as preventative maintenance. They seem to wear out on a lot of Ls engines rather quickly, and leak oil where the flywheel connects to the engine.

Re: List of LS problems. KISS
 

The oil consumption thing is a beast of many heads, and its also a talking point for the LS haters. There have been oil-rings to blame, PCV design (which did change slightly through the engines), and the least-talked about....maintenance.

If your seeing aggressive oil use, it sometimes boils down to what oil is being used, what weight of said brand, and under what mileage/conditions. It seems like nitpicking, but oil spec's aren't nearly as cut-n-dry as factory recommendations would allude;

Part of the problem is that many synthetic oils (even at the same weight), actually tend to run thinner than rated at the base rating, and lose their maximum viscosity* through the heat cycles (mileage and age are just used as a determinate factor, since its unreasonable for most companies to expect anyone to actually know the exposure to heat-from-friction that their oil supply see's in a given period). This is often one of the thing people notice when they buy an LS for the first time, and start running a high $ synthetic, only to feel like they are using more oil. On an engine that saw only 5-20 dino oil for 75k miles, the change to 5-20 full syn is actually a thinner oil, and more will pass by the oil ring. The LS engine and Royal Purple are not always friends for this reason in particular.

This also applies to the way an engine is being used. 3k miles on a weekend warrior may actually be MORE heat cycles and heat from friction than the same 3k in a commuter car. If your application requires it, its worth considering slightly upping your oil weight (for advanced users only, oil testing also preferred) OR going to a race application oil or straight-weight oil. For disclaimer sake, I'm not telling you to do this, I'm only shedding light on the beginning of a topic that is well beyond what most people consider when buying oil.

*Note I say viscosity and not lubricity. The oil companies will show bearing tests and results that "prove" a lack of breakdown by maintaining lubricity. Thats fine, but its not the same as maintaining viscosity. Lubricity is essentially "will it lube", and not "how thick will it be while lubing".

I highly suggest anyone spend some time on BobIsTheOilGuy if they feel like nerding out on this stuff.

Re: List of LS problems. KISS
 

:( engine is already in truck
I had to clean a bunch of oily residue from the intake when I replaced the gaskets
Added a catch can between the breather and intake while I was at it :)

edit: I'm really good with maintenance. As for oil, I think I dumped some 10-40 Valvoline Maxlife. Figured it's gotten the S10 to 155k miles, should do fine in the LS.

Re: List of LS problems. KISS
 

Oh I trust that, the oil in the intake is not a rarity. I picked up my lq4 with around 60-70k, still had crosshatching on the cylinder walls, looked to be very well maintained motor....and had a shop towel worth of oil to remove.

How did you choose to do your catchcan (vented, or pass-thru?)

Re: List of LS problems. KISS
 

Um, pass through I guess. It's a hose going to a can with a mesh material inside, another hose goes to the intake. The can came from eBay, originally had nothing inside (which I didn't like) so I made the incoming hose longer to reach the bottom. The air has to pass through some thick (but not dense) plastic mesh. (think more airy steel wool) Haven't put enough miles on it to know if it's helping yet.

Re: List of LS problems. KISS
 

Pass-thru isn't a technical term, its just the easiest way I know to separate it from vented ones. (I'm assuming the cap doesn't have a breather?)

Reason I ask is that this has been another one of those topics that results in confusion; some vent the can, some vent off a port on the v/c or on the oil filler, others don't vent at all, and yet others run the LS6 setup as well as a combo of the above. I'm kinda searching for some consensus on what people think works. I was under the impression that without at atmospheric vent, the crankcase would be allowed to still come under vacuum.