b005td

iTrader: (9)

Since there's a thread on whats the diff between the 6.0 I am here making one asking whats the diff between the 5.3L, I m planning on getting one of them, since they are dirt cheap. Some people told me not worth it, some said go for it, I m kinda confuse

dont quote me the wikipedia plz, everybody can find info there

V8 Supra Builder

iTrader: (37)

Some good reading here, as well as other GM Media publications

http://media.gm.com/us/powertrain/en...M7_L33_L59.pdf

Summary (emphasis added) :
Overview
With an outstanding balance of torque, free-breathing horsepower, fuel efficiency, low maintenance and low cost of ownership, the Vortec 5300 precisely suits the needs of working truck owners and vehicle platform teams alike. This versatility makes the Vortec 5300 the most widely applied of GM Powertrain’s Vortec V-8s.

The 5.3L LM7 V-8 was introduced in the 1999 Chevrolet Silverado and GMC Sierra, and developed in the tradition of the original Chevrolet small block using the latest, best overhead-valve technology available. A lighter valvetrain reduced friction and increased efficiency. A steel camshaft reduced mass while maintaining truck-grade durability. Steel roller rockers added stiffness, allowing greater engine speed with less vibration. Hydraulic roller lifters reduced friction for better fuel economy and wear resistance. The standard spark plugs extend anticipated plug life to 100,000 miles, while the coolant maintains its cooling and corrosion-inhibiting properties for 150,000 miles. Scheduled maintenance was limited to oil changes.

The Gen III Vortec 5300s share their engine block and, in most cases their cylinder heads, with the Vortec 4800 (RPO LR4,). The Vortec 5300s have nine mm greater stroke for an additional 520 cubic centimeters displacement. RPO L33, a lighter, higher output variant of the Vortec 5300 that became available on short bed, extended cab Silverado and Sierra models in 2005, features an aluminum engine block; cylinder heads from the LS6 that were originally developed for the Z06 Corvette; and a high-lift cam.

In 2002, GM Powertrain launched RPO L59 – the first flexible-fuel V8 for full-size sport utility vehicles. With the 5.3L LM4 in 2003, Powertrain offered the first all-aluminum Vortec V8. Continuous improvement has been the guiding principal for all of the Vortec 5300s. Since launch, virtually every component or system has been reviewed to increase value for the customer: management electronics, NVH control, materials, build tolerances, performance and efficiency have been enhanced annually, all with an eye toward conserving valuable resources and protecting the environment. Even required maintenance has been reduced. The industry’s best oil-monitor system records engine temperature, length of operation at a given temperature and several other operating parameters, then indicates an oil change when it's actually needed, rather than according to a predetermined interval.

Among 2005 upgrades, the Vortec 5300 was equipped with floating pin pistons, allowing tighter wrist pin to pin bore tolerances, quieter engine operation and enhanced durability. With the Vortec 5300, Chevrolet Silverado and Tahoe and GMC Sierra and Yukon models also received a Regulated Voltage Control (RVC) charging system to reduce wear on the alternator and improve fuel economy and electrically operated cooling fans for greater efficiency. In addition, Silverados and Sierras got a more powerful 145-amphere generator; Tahoes and Yukons, a more powerful 165 ampere generator. All vehicles with the Vortec 5300 also received a new accessory drive belt. Four-wheel-drive Silverados and Sierras with the Vortec 5300 received a new throttle progression in their Electronic Throttle Control (ETC), allowing more precise throttle modulation during severe off-road use. The Vortec 5300 also received an improved Throttle Actuator Control (TAC) module. Its PCM began using a rate-based diagnostics monitoring protocol to improve the robustness of the Onboard Diagnostics System (OBD II) and ensure optimal emissions control performance. Iridium-tip sparkplugs began being used to reduce potential maintenance and help maximum fuel economy and minimize emissions. And all Vortec 5300s began being shipped with GF-4 engine oil, which reduces deposits, extended oil change intervals, improved fuel economy and extended life of emissions control systems.

Mallory Cassels

So reading previous posts in this thread makes me comfortable that you all know what you are talking about. Here is my question/dilemma.

2005 Chevy Silverado 4x4 5.3L V8 FFV L59 8th vin Z, this is what I know about the truck's engine that we have. The truck got water in the engine and it blew out two cylinders on the crankshaft and the two rods connecting them to the pistons. The other six are fine. And of course the oil pan is toast. The truck after being thoroughly cleaned and having a oil change, spark plugs/wires, oil pressure sensor replaced and having a flush done still runs. Even with the two damaged rods and damaged crankshaft.

Here is my question (and let me know if you need more info, i'm not great on terminology)
1) Can we replace only the damaged parts of the crankshaft and rods smoothing out the centers where the rods go? And pistons if they are damaged, we haven't taken the motor apart from the top yet to see them.

2)Does the whole thing need replacing or rebuilding even if it still runs, albeit badly?

3)Do the heads need replacing or cleaning or anything because of the water (I keep hearing these mentioned but not sure what they are in comparison to the pistons and such (I'm great with outside parts of the engine, still learning inside stuff thought)?

And if we do have to replace it I have seen so many different types of 5.3L V8 FFV 8th vin T/Z that say not compatible that I am at a loss on knowing what would or would not work (these things are to expensive for guessing or maybes).

Can someone please help me out? The is so much info available that gives basic "what this is or isn't" but none that is very in depth or to the last letter "this is what an 05 Chevy Sil.... has"

dewchugr

Don't forget the LH6.

Shaggykjb

The most important thing to remember if your going to have this engine rebuilt is the Crankshaft. Replace it if you can afford it. Rockauto has them for under 300 bucks.
Just make sure you get the correct one, their not interchangeable..
black crank sensor = 24 tooth wheel
gray crank sensor = 58 tooth wheel

black sensor uses 12 volts.
gray sensor uses 5 volts.

The sensor is on the passenger side of the block near the dip stick. take a look and identify the color.

As for your rods. If I read the above post correctly, L59 got full floating pins. I believe that to mean their Gen IV rods. You can search the forum for somebody selling a set.
If not again, rockauto.com is your friend.
As for the bearings get new one for both the new crankshaft and rods. Cleivite 77 tri metal are good. Some use King.
Take it to a engine builder to assemble if you don't feel comfortable with a dial bore gauge and spending a few hours taking measurements for tolerances.
You'll probably want to have the cylinders honed lightly too if they were scratched from the break.

Hope this helps.

HotRodLS1

The LM7, L59 (flexfuel LM7) and LM4 (aluminum LM7) are "regular" gen III engines. This means they have a gen III block design, dished pistons, pressed piston pins and more. Further properties will become clear when looking at the L33.


The L33 is also refered to as a gen III engine, but, despite the similarities with the third generation, it's very much a gen IV engine I believe. GM compares the engine block with the LM4, both being aluminum and lightweigt. It's more like an ls6 block however and it possibly even has the LS2/gen IV structure. The L33 not only received bay to bay windows like the LS6, but also received shorter headbolts like the gen IV engines. As far as I know gen IV engines received this shorter bolts because the block structure was improved. If this is the case, then the L33 suffers less from bore distortion and also has better cooling pasages.

The pistons are flat top pieces. People often state the L33 received them from the 4.8 engine, but this just isn't true. First of all, the piston pin of floating pistons received a slightly larger bore. For the people who think GM took the 4.8 pistons and enlarged the piston pin bores, think again. The L33 came with LS6 and gen IV features, like floating piston pins, so why would GM use an old style piston? To reduce piston slap GM already introduced coated pistons in their LS6 that could be fitted with tighter tollerances, using the 4.8 piston would really be a step back. Next to this the 4.8 didn't switched to floating piston pins in 2005.
As mentioned, the L33 also received floating wrist pins and with it also came beefier rods. These are capable of handling more abuse then gen III rods, but properly tuned both can take a fair amount of abuse.
The L33 also received 799 heads. Together with offering a flat top piston with a floating wrist pin in the 4.8 engine in 2005 GM eliminated two product from their product line, making production cheaper. With this the L33 had lower compression and lower air velocity, but with the 2.00" intake valve the flow went up. Together with a camshaft that was expecially developed for the L33, the engine gained a little power over the LM7 and LM4.


All mentioned engines have a 24x reluctor wheel btw.

LS1ANDYG13

Ok I'm enjoying the info here much appreciated, my thing is i work at a salvage yard in Austin Tx and have access to Silverado 5.3 (L33) but all have high miles i did come across a 2005 trail blazer 5.3 (lm4) id like to use cause of low milage and it being all aluminum. i guess what i'm saying will an lm4 b ok to go with i do plan on upgrading heads and cam

JoeNova

That's not entirely true.

Yes, it received shorter head bolts. So did all gen 3 engines after 04.

Saying that the L33 didn't receive the flat tops from the 4.8 because they were all pressed pin isn't accurate either. The L33 is a 2005-2007 engine. All 05-07 Gen 3 4.8s also used flat top floating wrist pin pistons.

You say that the L33 couldn't have used the 4.8 pistons because they didn't switch to the floating pin until 05. The L33 wasn't released until 05. If it had been released in 04, this would have been a little less practical.

As for the rods, the LM7 received these rods in 05 as well.

I'm not sure which two products you think GM eliminated unless you're referring to the LM4 and something else?

"With this, the L33 had lower compression". It had half a point more compression than the LM7.

Comparing it to a gen 4 is silly. Comparing it to an 05-07 LM7 is a better comparison. It basically has an aluminum block and better heads than the 05-07 LM7.

JoeNova

I just replied to an old post. Damnit haha.

scout2000

Thank you for your reply.

Relatively new Gen III owner here, and found the entire thread educational.

G Atsma

Don't feel bad Joe. Good info is good no matter how we get it!

Camknute

OK I have a 2005 trailblazer ext 5.3 Lm4 the motor took a rod and I have a LM7 5.3 sitting on the floor in my Garage how difficult would it be to swap them

gmanbin

Hello all, I am new to this forum. Great info discussed. I need help on a similar topic.
I have a Gen3 02 gmc yukon xl (z)L59 (285hp) flex fuel with tons of engine issues and will like recommendations on a bolt on replacement engine other than the L59. If I can get better mileage with more horsepower even better. I do not want to replace transmission, wiring harness, computers etc. I heard engine swaps with these LS motors are common but I am having trouble with which will work. Please any and all help is needed, thanks in advance.

BCNUL8R

iTrader: (2)

Is the LM7 block missing some mounting bolt holes for accessories if you want to put it in a GTO? I thought I read that somewhere, but can't find it now.

HotRodLS1

I'll guess I'll have to shame myself..

Boost795

Depends on the year of the LM7 early ones (03 and older I believe) didn't have a returnless fuel system, and are not fly by wire (like your trailblazer should be) and you will definitely have to swap the oil pans as the LM4 has a hole in it for the axle shaft that the LM7 will not have since it came in a full size truck. However if you use the intake and fuel rails from your old engine it should bolt right in place unless the tb's have a different motor mount location due to a smaller engine compartment (I doubt it, but I wouldn't be surprised) also I'm not sure on the accessory drives they MIGHT be different, again do to E.C. size. Basically use the long block (heads and block)from the LM7 and you will be fine.

Boost795

You should be able to use any GenIII engine as long as you use your old electronics and it has the same crank sensor (grey vs. Black)
Edit: I forgot your injectors are going to be different than any of the other engines due to being flex fuel swap them as well into the new intake.

Davestahoe17

I have a 5.3 that im rebuilding and unfortunately forgot to mark pistons where they came out and there not marked on the side only have red marks on 4 of the connecting rod caps any idea of what i can do

JoeNova

You can put them in any cylinder, its not that big of a deal.

dawgs74

what is gf-4 engine oil?