Jump to content

Iron Block Vs. Alum Block

joe04

Recommended Posts

joe04 Enthusiast

joe04

Posted
Posted

Hey guys,

Dumb question? I'm shopping for an '08 4WD, and I'm seeing Iron Block, and Alum Block 5.3's. What are the pro's and con's of each. Besides the Iron block weighing more. (sorry) I know someone was waiting to jump on that.....Thanks in advance.

joe04 Enthusiast

joe04

Posted
  • Author
Posted
Iron rusts, aluminum doesn't. but Aluminum does corrode if you live where they throw salt down in the winter

I JUST knew we had someone out there with all the answers!!!

ajcain79 Enthusiast

ajcain79

Posted
Posted

I think that the aluminum block would dissipate the heat better than an iron block.

gvbhunt Enthusiast

gvbhunt

Posted
Posted
The iron block has more Cojones. The aluminum block is lighter.

The Aluminum block is definately lighter, also isn't the Aluminum block the HO engine? I know on the 2005 it was, the L33 was the aluminum block and was 20hp more than the cast iron block (315 vs 295).

 

Also I would think that since the block and heads are both made of the same metal that they would expand and contract at the same rate and you would have less chances of a head gasket leak?

Silverado4x4 Senior Enthusiast

Silverado4x4

Posted
Posted
The iron block has more Cojones. The aluminum block is lighter.

The Aluminum block is definately lighter, also isn't the Aluminum block the HO engine? I know on the 2005 it was, the L33 was the aluminum block and was 20hp more than the cast iron block (315 vs 295).

 

Also I would think that since the block and heads are both made of the same metal that they would expand and contract at the same rate and you would have less chances of a head gasket leak?

 

Naw those days of leaking heads from a aluminum heads and iron blocks are pretty much gone cause of the new gasket materials they have now compaired to years and years ago.

pckhalil Enthusiast

pckhalil

Posted
Posted
Iron goes in the regular cab and extended cab, and aluminum goes in the Crew.

 

 

Aluminum block is available on any model of half ton, check the website or a dealer and you'll find plenty of ext cabs with aluminum blocks.

 

My guess is that GM doesn't have the production capacity to produce only aluminum blocks; some percentage of their engine plants are still tooled up for iron blocks.

 

Or it could just be to satisfy the people that don't think an aluminum block will hold up as well as iron.

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
How do you know if your truck has an aluminum or iron, is it in the vin? I have 2007 ext cab Z71 nbs.

 

Open your hood and look at it?

VT_Z71 Enthusiast

VT_Z71

Posted
Posted

Isn't the FlexFuel motor one in particular.....i'm thinking Aluminum?

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      Getting greedy...   The AC pump has been replaced at least once per service records, and it's been recharged twice since 2018 or so, in approximately 2 year intervals between those charges.   It was done at the same shop...clearly they were enjoying the revenue of recharging the system periodically versus actually tracking down and fixing the leak. I learned that the owner was 88 years old when she passed in 2023, so maybe they assumed only a temporary fix was needed anyway.   The system is basically empty now, the compressor spins freely, so I'm guessing it "just needs a recharge".   I vacuumed it down, and it has basically held overnight. Doesn't appear to leak under vacuum, check! So it must leak under pressure. I don't have a way to pressurize the system and pressurizing it with shop air wouldn't be great for the air dryer (which is probably toast anyway?)   The dryer (accumulator? I'm not an AC expert) has a Schrader valve, but the high side has an old ball-type valve, which are notorious for leaking. It's clearly had schmutz blown out of it at one point because the line/area next to the valve is coated old black crud, which I assume is AC refrigerant residue/oil, or maybe even dirty dye. I think I'll roll the dice and replace the valves. I have a black light around here somewhere so I'll find it and shine it around the engine bay in the dark to see if there's any dye.   I can't think of another way to track down the leak other than injecting some dye (if it doesn't have any) and having it charged up. We can't buy R134a off the shelf here anymore, so I'll run it up to Jiffy Lube and have them do it. I think I have a coupon. At the very least, the charge should last long enough for a year or two, according to history. I think this truck will be long gone by then. But cold AC is a selling point.    
    • clowe1243
      6.2L L87 Powertrain Engine Noise (Lifter Failure) Question

      By clowe1243 · Posted

      Got the truck back today.  Called them yesterday to get an update, and miraculously my truck is finished?!?! The $13k out the door was complete bullshit!  Ended up being over $14k.  They added some bullshit service bulletin that I cant even find, where they replaced my radiator without telling me or asking me, and charging me for it.  Need to do more research into it, cause they leaked the first delivered radiator was ran over by FedEX.  Sounds like bullshit to me. 2.5 Months for an engine swap, which ended up being remanufactured, not new; ****ing ridiculous.  Brakes are squishy as hell, not sure if its from sitting.  Will give a couple days to see it that figures it self out.  GAVE IT BACK TO ME WITH 1 GALLON OF GAS!  Just filled the tank the day before drop off, more bullshit.  My dash cam SD card was formatted, not really much I can do about that. 3 year, 100k GM warranty at least.  Time to sell it and say **** off to GM.  Bad experience.  Cant wait for the survey email to come through.  Overpriced Raptor R, here I come!
    • haoleboyZ71
      Radio Update

      By haoleboyZ71 · Posted

      If I forget the phone in the truck, and forget the truck in the phone, and reconnect.  It works great for the day.  Truck sits overnight, and the next day is a no go.  It will connect Android Auto via usb cable, but not bluetooth.   Ive tried Everything in this thread so far, and nothing works for more than a day.   I think I might have to go to the dealer and have them flash the pcm.   thanks for all the suggestions guys. 👍
    • Bill Lemmond
      primary drive belt tensioner

      By Bill Lemmond · Posted

      2022 2500HD Crew Z71 Duramax single alternator.  Recently had the primary (water pump / fan) belt tensioner pulley bearing to fail while hundreds of miles from home of course the plastic pulley melted and belt shredded which took out some wiring. Found a replacement tensioner assembly and belt to continue now would like to find a replacement for just the pulley and bearing to have a spare assembly in case of a repeat, the rest of the tensioner is fine. Has anybody here found a correct replacement part for just the pulley and bearing? Any help is appreciated.
    • Atlas
      Upgrade to a 2026 AT4 with the 3.0L Duramax

      By Atlas · Posted

      +1 for the 3.0   Perfect for 1500 pickup towing duties.   Perfect engine for a 1500 pickup period. Huge torque at stunningly low RPM makes it feel a lot lighter than it is. The fuel mileage is insane for a tall and heavy 1500... 30+ on the highway. Mid 20's around town.   It's probably not perfect if you bought a 6.2 for the braaaaaaapppppp V8 noises and wrapping it out to 6k. The LZ0 acts and sounds like a small turbo diesel and there's nothing you can do to make a small turbo diesel sound like a big one, and you can't make an inline diesel sound like a V8 diesel/big Duramax. It's a different driving experience altogether.   Drive one, I think you'll like it, though...

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...