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2008
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50 Posts
Discussion Starter · #1 ·
Hi,

My only concern in purchasing the TB we picked out was the DoD 5.3 engine and "how durable has it proven to be?"

Before we bought the TB, I did some research on the engine but found very little information. No...I didn't find this site until after we bought it. :duh:

So how has this engine been for anybody? Any "common" issues to watch for? The good, the bad, and the ugly please!

I'm anal about taking care of my vehicles and want to learn as much as I can about this engine!

:thx

GD
 

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2007 gmc
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11,894 Posts
the 5.3 has been around for a while. The only difference between a standard 5.3 and the DoD is the electronics that control fuel and spark. That being said the engine itself is a very good engine as with most small block V8's.

I have not heard of any major issues with the electronics on the DoD.

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2008
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Discussion Starter · #3 ·
the 5.3 has been around for a while. The only difference between a standard 5.3 and the DoD is the electronics that control fuel and spark. That being said the engine itself is a very good engine as with most small block V8's.

I have not heard of any major issues with the electronics on the DoD.
Have you heard if anybody has ever disabled the DoD feature? Or even can you disable it?
 

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2006 chevy trailblazer_lt
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The only knock on these engines that I'm aware of is a tendency for some of them to use oil. This is supposedly due to either a valve cover issue or to an "overactive" lifter or three, or both.

Do some searches and you'll find the threads.

I have the 5.3 and love it even though it does use about a quart every 2000 miles.
 

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Discussion Starter · #6 ·
The only knock on these engines that I'm aware of is a tendency for some of them to use oil. This is supposedly due to either a valve cover issue or to an "overactive" lifter or three, or both.

Do some searches and you'll find the threads.

I have the 5.3 and love it even though it does use about a quart every 2000 miles.
I did see threads on this. Have you had the lifters checked and the valve cover issue addressed?
 

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2006 chevy trailblazer_lt
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Nope. Living with it.

If it ain't broke, don't fix it is my motto, and one quart per 2000 miles is much better than I ever got when I was young.
 

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2003 gmc envoy_slt_xl
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At 75000 I have 2 broken manifold bolts and blown head gasket.....

Engine has run well till now but all the ignition switch - rotting gas lines and other gremlins - and now this stuff just ticks me off.

Engineered just a little too close to the margin if you ask me - kind of like a Ford lol....

Enjoy
P:woohoo:
 

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2007 chevy trailblazer_ls
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3,700 Posts
At 75000 I have 2 broken manifold bolts and blown head gasket.....

Engine has run well till now but all the ignition switch - rotting gas lines and other gremlins - and now this stuff just ticks me off.

Engineered just a little too close to the margin if you ask me - kind of like a Ford lol....

Enjoy
P:woohoo:
Testing has shown average longevity to be about the same as the iron block 5.3...

I would think it would be much less likely to pop a head gasket than the iron block / aluminum head version in the trucks, because of the different expansion rates of steel vs aluminum causing it to be a more fluid mating surface than ours, that expands at the same rate between the block and heads.

Have you ever changed the coolant? Have you added anything other than DISTILLED water to top the coolant back off (water evaporates out of dexcool)... You would have surely had to add some, as I had to refill my burp bottle at around 30k miles.

Mike
 

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2007 chevy trailblazer_ls
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LOL ...

Between the loss of coolant - and no dripping but a hissing in the back....

And the gunk in my oil - ....

Easy math problem...
re-read my post... I'm not asking how you know it's a popped head gasket. I'm asking about past maintenence, like if you ran the thing with tap water in the system (you HAD to have at least topped it off before, so did you use tap water, or distilled water?), or if you had changed the coolant before, did you put green coolant in it, or if you had let it get low on coolant via evaporation, which caused it to overheat?

Mike
 

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2004 buick rainier
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At 75000 I have 2 broken manifold bolts and blown head gasket.....

Engine has run well till now but all the ignition switch - rotting gas lines and other gremlins - and now this stuff just ticks me off.

Engineered just a little too close to the margin if you ask me - kind of like a Ford lol....

Enjoy
P:woohoo:
DOD(AFM) available 2005-2008 Yours is not.
 

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LOL ...

Between the loss of coolant - and no dripping but a hissing in the back....

And the gunk in my oil - ....

Easy math problem...
I hadn't thought before about what it was, but from this post, it's not as easy as you think... From the symptoms you posted, I'm going to say it's the lower intake gasket, for a couple of reasons...

1. I've never been able to hear a head gasket leak... Usually, head gasket leaks are so keep inside the metal, that you can't possibly hear them. The lower intake is plastic, and you could very possibly hear a leak.

2. As mentioned above, with the lower intake being plastic, it expands at a different rate than the aluminum block and heads (which expand at the same rate as each other). When you've got a leak you can't find, the FIRST place to check, ALWAYS, is the most fluid joint in the engine, as they're the most likely to fail... The most fluid joint in this engine (that has coolant flowing through it, that could drain into the oil) is the lower intake manifold.

Mike
 

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2003 gmc envoy_slt_xl
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Well after more research there is a posting with Aldata and some other GM techs that on 5.3s if you are losing coolant into the oil, the odds are the head is cracked. I now have to take off the valve covers to check the head casting numbers but there is a series that were defective.

I will keep you informed !!!!!!!!!!!!!!!!!!! LOL....:bonk:
 

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GM TSB# 06-06-01-019B (came out 06-12-2007)
Subject: Information on Gradual Coolant Loss Over Time With NO EVIDENCE OF LEAK FOUND

[/b]

Models:
2004-2006 Buic Rainier
2001-2006 Cadillac Escalade
2001-2006 Chevrolet Avalanche, Blazer, Silverado, Suburban, Tahoe, and Trailblazer
2001-2006 GMC Envoy, Jimmy, Sierra, and Yukon
2001-2005 Oldsmobile Bravada
2005-2006 SAAB 9-7X

With 4.8L or 5.3L VORTEC GenII, GenIV; V8 engine (VIN's V,T,M,M,Z --RPO's LR4, LM7, LH6, L33, and L59

Information:

Some vehicles may experience a gradual coolant loss over time. A very low percentage of cylinder head(s) manufactured with an embossed Castech logo may develop a porosity crack in a very specific area.

Inspect the cylinder head assembly to determine if the casting was manufactured by Castech. This can be accomplished by inspecting for their casting logo located on top of the intake port, under the rocker arm support rail and in the spring deck cavity portion of the cylinder head.

Important: If the cylinder head(s) are Not a Castech casting, follow normal diagnostic procedures in SI to determine the cause of the coolant loss.

Refer to the following illustrations on how to identify Castech casting and/or the very specific areas of the cylinder head(s) for a coolant leak from porosity.

If the cylinder head(s) is a Castech casting (1), inspect the area around the five oil drain holes for witness marks indicating coolant seepage over time (2).

Important: If No evidence of coolant loss is found on inspection of Castech casting cylinder head(s), follow normal diagnostic procedures in SI to determine the cause of the coolant loss.
The crack location can be found in any of the five cylinder head(s) oil drains. This can be seen as a clean or shiny area, on an otherwise stained surface (1). Pressurizing the cooling system at this time may reveal coolant, air, or a combination, weeping in the described area. If inspection reveals evidence of coolant witness marks (1), replace the entire cylinder head(s) assembly.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information. WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

© Copyright General Motors Corporation. All Rights Reserved.
--------------------------------------------------------------------------------------------------
:hopeless:suicide::bonk::nono::crazy::x:x:x:sadcry:
 

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2007 chevy trailblazer_ls
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... so it takes you ~3000 miles to empty the burp bottle?? If it's less than that (like a hundred miles or something), it's almost surely a gasket... Porosity cracks don't typically just DUMP fluids... That's why there's the bottom paragraph in the TSB...

Mike
 
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