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LQ4 to LY6 Engine Swapp 2002 2500HD

jeffglitman

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jeffglitman New Member

jeffglitman

Posted
Posted

Hi Guys, I am new to this site and am looking to bring my tired old 2002 2500HD Silverado back to life. It has an original 6.0L LQ4 engine GM Part# 89018180. I do a lot of work on cars and trucks but this being my toy hauler, I am looking for a quick swap of engines. Has anyone every swapped in a newer version LY6 engine? I can still get a fully loaded "New GM" engine and was wondering if this would even work. I understand that the LQ4,LQ9 & LY6 share the same old Cast Iron block but the LY6 has the newer L92 heads.

 

I believe all of that so far will work ok an fit an bolt up of my accessories will not be an issue. The problem I foresee is the LY6 has the VVT. I see Summit Racing and others have the VVT Delete Kits available which included a new Cam Gear and front timing cover. (http://www.summitracing.com/parts/cmb-09-0027/overview/).

 

 

I have read other guys install such a kit but they always upgrade the cam, valve springs and pushrods to a beefier cam. I am looking to just delete the VVT option and drop this into my truck keeping the stock ECM program.

 

In Short, has anyone done this or know if it will work?

 

Thanks in advance for your help guys.

 

Chris Senior Enthusiast

Chris

Posted
Posted

Nope nope and nope. They dont share a block. To keep the same everything, look for LQ4 or LQ9. LY6 is a Gen 4 and requires a new harness and computer. you can put L92 heads on the Gen 3 engines, you just need a new intake manifold and run some custom plumbing

  • 2 weeks later...
jeffglitman New Member

jeffglitman

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  • Author
Posted

Thanks Chris, but maybe I wasn't clear. I have a chance to buy a brand new complete GM crate LY6. This is an overstock engine that GM would send to dealerships in case they needed to swap out an engine under warranty. I know crank,cam and knock sensor will need to be re-wired due to change in locations. Will this engine physically fit in place of my LQ4 in my 2002 2500HD? If I do the VVT delete, then can't my existing ECM work or even if I have to get it reflashed? Also saw some folks using the lingenfelter TRG-002 58X-24X CRANK SENSOR TRIGGER CONVERSION MODULE.

 

I can live with minor mods.

kstruckcountry Senior Enthusiast

kstruckcountry

Posted
Posted

It's not going to be minor, I don't believe it even is a direct fit physically. It won't talk to your stock ECM without some serious changes. I'm sure it's doable, but if you're getting too great of a deal to pass up, buy it, sell it, and pickup up an LQ4/9 for cheap.

 

I would talk to Pacific Fab, they can give you the closest to plug and play if you really want to do it.

Chris Senior Enthusiast

Chris

Posted
Posted

Your current ECM will not run it. Motor mounts and everything on top is different than your LQ4. It may be a great deal, but in time and parts to make it work, getting a crate LQ4 makes more sense.

 

Basically youre looking at motor mounts, flex plate, ECU, standalone 4L80e trans controller, full gen 4 engine harness, custom fabbed intake setup, new fuel lines because yours has a return and anything 04+ does not, new fuel punp, new inectors, and your gauges not working

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