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Discussion Starter #1
The daughters truck has the 5.3 Vortec (LM7) off the Vin. Will that swap in as easily as the LS line with regards to the electrical?

Haven't seen the truck yet, but it got sideswiped on the freeway today....

Might be time to start looking at a frame up restoration project...
 

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I did a quick Google search of lm7 vs ls and didn't see much about wiring difference but from what I saw its 100 pounds heavier
 

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I did a quick Google search of lm7 vs ls and didn't see much about wiring difference but from what I saw its 100 pounds heavier
The extra 100 lbs. is the iron block that all ‘99 and up LM7’s shared. The lighter LS referenced weight are aluminum block versions with cast iron sleeves.
 

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I put a LM7 in mine. very easy to do. Need only 4 wires to the jeep harness and the thing runs.
 
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Discussion Starter #6
I put a LM7 in mine. very easy to do. Need only 4 wires to the jeep harness and the thing runs.
No computer anything in my 89 but if I found say a 94 or 95, will that need any of the computer from that. Emissions will be a non issue, but timing and fuel etc?
 

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Your jeep year or model means nothing for making the engine run... the computer will come from the truck

You will need to address gauges tho
 

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If you swap a LM7 in there, forget about Jeep and think Chevy. The only thing you need is the computer from the engine, a ground wire, 12 Volt constant to the ECU, hot while cranking and hot in RUN. You can use some wires from the jeep for the gauges. Volt, Temp, Fuel.
 

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Thanks all, Jury is still out on the truck, accident was not her fault, truck is still driveable, but she was getting ready to sell it for something more useful to her lifestyle, had a cash buyer lined up but now we will have to see what the insurance co's are going to do. A decent check from them and I may just make up the difference and keep it till I find a suitable project YJ.
 

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If you swap a LM7 in there, forget about Jeep and think Chevy. The only thing you need is the computer from the engine, a ground wire, 12 Volt constant to the ECU, hot while cranking and hot in RUN. You can use some wires from the jeep for the gauges. Volt, Temp, Fuel.
Depends on what year LM7, I swapped a '05 into my YJ. It's a drive by wire, so I needed to reuse the truck throttle pedal and tac module.

Also I recommend finding the transfer case adapter from a mid 90s s-10 and a 231c transfer case. Much cheaper than buying an adapter for a 231j.
 

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But also longer
GM adapter is 3-4" longer, but can be had for $20-30 (Novak is asking almost $650) and the GM doesn't require a disassembly of the transmission but you need to make your own speed sensor.

I'm running a '05 LM7, 4l60e, 321c/j hybrid with sye (standard rear driveshaft no CV) and a 8.8 with no body lift, no t-case drop and 2.5" spring lift.

Rear driveshaft is 16" joint to joint (1.5" longer than stock)
 

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Look if ur gonna start talkin dirty ur gonna have to post some pics too ;)
 
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