Anyone doing the 02 LB7 to LLY conversion harnesses?

turbovan

Too many toys!!!
Mar 4, 2018
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Abbotsford, BC, Canada.
Been out of the loop for a few years, but back in as my truck just blew its head gaskets and want to run the LLY stuff. Anyone doing the harness conversions anymore? Thanks.
 

2004LB7

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Dec 15, 2010
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not sure you can do a direct 02 lb7 to lly. I thought the comms between the modules where different. the only way I thought you would be able to do it would be to change out all the modules, bcm, dash, ecm, tcm, ficm and any others that won't communicate or use the lly top end and use the lb7 electronics to drive the lly injectors. 03 and up where supposed to be easy since they use the same communication between modules
 

Chevy1925

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Oct 21, 2009
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Phoenix Az
not sure you can do a direct 02 lb7 to lly. I thought the comms between the modules where different. the only way I thought you would be able to do it would be to change out all the modules, bcm, dash, ecm, tcm, ficm and any others that won't communicate or use the lly top end and use the lb7 electronics to drive the lly injectors. 03 and up where supposed to be easy since they use the same communication between modules

Nope, my 02 was converted to lly. You need an OS patch in the tune for the oil pressure sensor to work right and redone main harness from trans to engine. You will be lacking the g solenoid in the trans but it ain’t needed. Need the lly nsbu too

Tcm can be reused, with factory os

Ficm needs to change to lly

Ecm needs to be lly

Bcm can stay as can the dash
 

2004LB7

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Dec 15, 2010
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Nope, my 02 was converted to lly. You need an OS patch in the tune for the oil pressure sensor to work right and redone main harness from trans to engine. You will be lacking the g solenoid in the trans but it ain’t needed. Need the lly nsbu too

Tcm can be reused, with factory os

Ficm needs to change to lly

Ecm needs to be lly

Bcm can stay as can the dash
that's good. guess I'm still working with some outdated information
 

rfletes79

Active member
Mar 5, 2010
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Galt, Ca 95632
not sure you can do a direct 02 lb7 to lly. I thought the comms between the modules where different. the only way I thought you would be able to do it would be to change out all the modules, bcm, dash, ecm, tcm, ficm and any others that won't communicate or use the lly top end and use the lb7 electronics to drive the lly injectors. 03 and up where supposed to be easy since they use the same communication between modules

It’s possible. Very similar to the 03/04 Lly swap, in fact 100% of the modules are the same for this swap (01-04). Just needs the Lly chassis harness modified and the right Lly tune. Technically any Lly tune will work and run, but without the correct one your ac won’t function.

As far as the eop, you’ll Need to keep the 01/02 sensor and wire it directly to the cluster as this info doesn’t get fed into the ecm for the 01/02 trucks. That’s one of the mods done to the Lly harness to make it plug n play just like the 03/04 trucks.


Sent from my iPhone using Tapatalk
 

2004LB7

Well-known member
Dec 15, 2010
6,274
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Norcal
It’s possible. Very similar to the 03/04 Lly swap, in fact 100% of the modules are the same for this swap (01-04). Just needs the Lly chassis harness modified and the right Lly tune. Technically any Lly tune will work and run, but without the correct one your ac won’t function.

As far as the eop, you’ll Need to keep the 01/02 sensor and wire it directly to the cluster as this info doesn’t get fed into the ecm for the 01/02 trucks. That’s one of the mods done to the Lly harness to make it plug n play just like the 03/04 trucks.


Sent from my iPhone using Tapatalk
so is the difference really that 03/04 is more plug and play as the harness is mostly the same as the lly?
 

turbovan

Too many toys!!!
Mar 4, 2018
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Abbotsford, BC, Canada.
Thought I'd update, LLY is in, what a nightmare piecing together different engines to make one-using LMM, LLY van and LB7, lol. Aftermarket dp doesn't fit properly so that has to be fixed tomorrow.
His harness fits great, hopefully have it running this week.
I am calling my engine, LL7.
 
Last edited:

Bdsankey

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Feb 1, 2018
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Thought I'd update, LLY is in, what a nightmare piecing together different engines to make one, lol. Aftermarket dp doesn't fit properly so that has to be fixed tomorrow.
His harness fits great, hopefully have it running this week.
I am calling my engine, LL7.
You wouldn't be the first to use that designation, glad to see it sticking around!
 
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turbovan

Too many toys!!!
Mar 4, 2018
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Abbotsford, BC, Canada.
Well, midnight last night, turned over but did the start and die, did the manual relearn of the vats but wouldn't learn, have 2 codes pertaining to it. Waiting for my tuner to show up and put in Ricks base cal to eliminate the theft system and other things
 

turbovan

Too many toys!!!
Mar 4, 2018
145
20
18
Abbotsford, BC, Canada.
Ok finally got the brakes bled, fluids all topped up, trans cooler replaced and first test drive, WOW. This is insane, turbo literally lights up off idle and the power, damn. All these years with my slow LB7, hahaha. Oh, no tune either, idle lopes due to LMM fuel pressure reg. The 2 weeks of work was actually worth it.
 
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