Iron Block Vs Aluminum Block

[085300]

Ok, this might be a stupid question but...

 

What's the difference between an iron block 5.3 or an aluminum? Pros/cons? Difference in power? Reliability? Cost?

 

What are your thoughts and what block do you have?

 

I have an iron block.

[robertmagni]

I am not an engineer I would say the iron block for trucks is just for durability under all conditions, and the aluminum blocks are more performance oriented motors (camaros vette's and others) all depends what you want I have seen a lot of fast iron blocks 12 seconds and alot lower than that though. Nothing makes me happier than to be watching PINKS and see a Mustang with a LS motor in it, and the guy says it was way cheaper to go faster with the LS motor!

Robert

[Ranger]

Iron blocks are less prone to "cracking", but having aluminum heads makes for some sealing issues from what I hear.

[cujo8]

Here's a link to what the differences are:

 

http://www.gm-trucks.com/forums/index.php?...95383&st=15

 

BTW the LM7 and L59 5.3L are both iron blocks and the L33 5.3 has aluminum heads and block w/ iron cylinder sleeves.

[1990ss]

One difference I've noticed with my aluminum block is that it warms up ALOT faster in the winter than iron blocks. Aluminum blocks also weigh quite a bit less too.

[085300]

One difference I've noticed with my aluminum block is that it warms up ALOT faster in the winter than iron blocks. Aluminum blocks also weigh quite a bit less too.

 

 

 

Yep. I know that from living in Maine, aluminum blocks blocks warm up much quicker, but are more prone to warping if you dont let them warm up.

 

So.. Why are some trucks aluminum and some iron? From GM's point of view??

 

Would an aluminum block engine be faster in the same vehicle because of weight alone?

[05silvycrew]

Here's a link to what the differences are:

 

http://www.gm-trucks.com/forums/index.php?...95383&st=15

 

I always wondered why the aluminum blocks achieved 15-20 more HP than the iron blocks. thanks for the info . Really wish I would have had that knowledge prior to buying my truck. I guess back then I thought all 5.3's where the same.

[cujo8]

GM only used the L33 aluminum version 5.3L from 2005 to 2007 and only in extended cab 4wd Silverado and Sierra 1500 trucks. A fully dressed L33 weighs 100lbs less than the LM7 & L59 versions of the 5.3L.

[AirForceAngler]

My '08 Crew Cab Z71 4x4 has an the aluminum block/heads. Not sure if it's the L33 or not, but I think this motor was used in all the 1500 Crew Cabs.

[Zembonez]

The difference is weight. Pure and simple.

 

There are different internals and head designs used in different generations of both blocks. These result in small differences in HP ratings but have nothing to do with block composition.

[music]

...I think this motor was used in all the 1500 Crew Cabs.

 

 

More specifically, the aluminum 5.3L is standard in 1500 Crew Cab 4wd trucks, I suppose to help compensate for the extra weight.

[602505]

Not sure if all 1500 crew cabs were supposed to have the aluminum block or not but my 05 5.3 crew cab has the Iron block along with 4.10 out back.

[Kazadog]

Is there any way to tell what material the block is made of?? Is there an engine code or something in the build sheet??

 

Cheers

 

KD

[no bull]

Is there any way to tell what material the block is made of?? Is there an engine code or something in the build sheet??

 

Cheers

 

KD

 

Look for rust=cast iron

 

no rust=aluminum

[VMax2007]

Is there any way to tell what material the block is made of?? Is there an engine code or something in the build sheet??

 

Cheers

 

KD

 

Open your hood and look at it.