thinkin of a lly into lb7 swap

[motojoeis01]

so ive been trying to research how hard it would be and what all i would have to do. there is a guy on one of these forums that has done it but he cut and spliced his wire harness. i dont see why i cant just unplug the main harness connectors at each motor and switch the engines, plug them back in and just change out the ecm, tcm, bcm just to make sure it all works. i know people will say its expensive and ask why. i dont want to keep putting injectors in my lb7 dmax, i have 226k on my truck now. i just picked up the front half of a 2004.5 lly dmax truck with everything. engine, trans, transfer case, complete harness, radiator, intercooler, everything! pretty much he cut the truck behind the transfer case and sold me the whole front end for $600. and it only has 90k on it. so thats why i want to do the swap. get rid of any future problems and have a low milage drivetrain. any help would help alot. anyone that has thought of it or has done it i would love to hear your story. i belive the harness connectors are the same, so i guess i can only try and see if it runs? lol

 

[THEFERMANATOR]

If this is for the 03 in your sig, then yes you can swap out the LB7 for an LLY pretty easily if you have all of the harness's for under the hood. 03+ use a pretty much universal wiring system and swap out pretty easily.

 

[duratothemax]

very easy, as the fermanator said. Plug and play. You should not have to do any splicing at all or anything else special.

unplug the LB7 main harnesses under the UBEC (underhood fuse box) and plug in the LLY harnesses.

ben

 

[SmokeShow]

sure wish it were that easy for the 01-02.

 

[RENODMAX]

i may be crucified for this but ive thought of doing the same. lb7 injectors are garbage.

 

[RKTMech]

Damn $600....merry xmas!!!!

 

[RENODMAX]

Damn $600....merry xmas!!!!

No kidding. I am hoping that if/when i do the swap that I can sell my motor to make up some of the difference.

 

[Blueox03]

That's a hell of a deal! the front cap is worth mor than that....

 

[Budice69]

How did the swap go, any unexpected problems?

I would like to hear the results, I too am looking to replace my LB7 with a more reliable fuel system

 

[floorguy]

New to the forum and I've got almost the same situation going on here. My 05 w/70k caught fire from bed to cab and insurance co sold it back to for 154 bucks. I've got all the electronics under the hood(box, computers, harnesses). My question is about smokeshow's comment that he wishes it were that easy for the 01-02. Why isn't it? Thanks for any insight.

 

[SmokeShow]

major electric system overhall on the trucks in 03... pretty much NOTHING will be plug n play for the 03+ into the 01-02 short of replacing all wiring AND hardware. This includes things in the cab like the BCM and gauge cluster. Heck, I think the door switches are even wired up different. While that probably won't create an issue with the drivetrain swap, it's still a difference.

Like was said, 03-04 LB7 is relatively easy (apparently) to convert to LLY because it's based on the same wiring system. Not the case with the 01-02 lb7.

If I'm off base a little, duratothemax, ferminator, cougar or someone will set it straight. Those guys know the in's and outs of the wiring on these trucks FAR better than I ever will. This is just how I remember it being explained. I do believe at least one person has successfully (or so it seems but I don't have 1st hand experience of it) used the 01-02 wiring to drive the LLY electronics but I don't know what it took or how well it actually works. Wanna say he used the LB7 FICM to control the LLY injectors but just don't know for sure.


Good luck. :thumb:

 

[THEFERMANATOR]

https://www.duramaxdiesels.com/forum/threads/i-have-seen-the-impossible.16887/

Also IOWA LLY here has an 03 with LLY heads and injectors swapped in.

 

[tdrost]

Hey guys, I see that this Is a very old thread, but I am in the process of having an know lly swap done on my 04. I have the complete engine with turbo, ecm, ficm, pass intercooler pipe, and nsbu switch. I have the main wiring harness, but if anyone here has the one to plug in under the fuse box and go out to ecm, tcm, and tranny, please let me know. Also this is my first post, soo I apologize for bringing this tread back but I can't start my own thread yet.

 

[Dee Perry]

lly swap

I am also new to this site ad I must say you guys are more helpful than any other site I have seen. I am in the middle of the 03 lb7 to lly swap. Have all the parts except the NSBU, do I need to swap the NSBU?

Thanks

Dee

 

[THEFERMANATOR]

I am also new to this site ad I must say you guys are more helpful than any other site I have seen. I am in the middle of the 03 lb7 to lly swap. Have all the parts except the NSBU, do I need to swap the NSBU?

Thanks

Dee

Yes, the 03 truck is most likely the dual plug NSBU whereas the LLY will be a single plug NSBU.

 

[bigbopper]

bigbopper

i put an 08 engine complete in my 01 ,using all 01 electrontics ,ecu ,ficm ,sensors and all ,tuned by my hp tuner:george

 

[Big Block 88]

^^^^:thumb: me want

 

[novaman64]

i put an 08 engine complete in my 01 ,using all 01 electrontics ,ecu ,ficm ,sensors and all ,tuned by my hp tuner:george

pics?

 

[james13]

I'm doing now in my 02

 

[Dee Perry]

hey guys, just finishing with the lly swap from lb7. The swap was as mentioned a piece of cake. The bad news is I cant get it to fire. Have done the eergency re-learn twice with no success. Crank for about 3-5 seconds, leave in run position for 11 minutes, security light goes off in about 9 minutes, crank again and repeat three times. No fire. Am I missing something?