Just bought an LS drivetrain.

[Kane]

I just picked up this LS/4L60E combo to install in my Jeep over the winter. This was part of my original plan when I rebuilt my Jeep but the budget forced me to stay with my 6 cylinder at the time. I did swap in an AX-15 and installed a Howell injection system that I got for a good deal but I am a horsepower guy and it just never fit the bill for my Jeep. I know a lot of people on here have done this swap so I may have questions as I move along. I am quite well read up on the swap and it doesn't look all that difficult to me but the little odds and ends and small tricks are things you don't know about until you need to. I am pretty excited and will be buying the rest of the swap parts over the next month or so to be ready for change. I plan to remove the old motor after I get everything I think I need so I have plenty of room to rework the fuel lines and wiring. Right now I am torn on converting the stock ECU and harness or just dropping the cash in the Holley Terminator X Max system which might save me money down the road when I do upgrades. It isn't cheep but is could be in the long term. My exhaust is already 2.5 inch and will suffice for the stock LS motor after I tie it in.
So my first question for anyone who knows. Advance adapters sell their kit to tie in the dana 300 and they use a conversion shaft at the transfer case while Novak changes out the output shaft of the transmission. I am incline to use Advance Adapters so because if it breaks it will be easier to pull just the transfer case out for repairs. Which kit is stronger?

 

[mysunnshine]

I will recommend that you use the original ECU because it has good logic in it and a replacement harness is only about $600.

 

[Dave The Sparky]

I got an AA adaptor and installing it involves cutting the output shaft down a little on the 4L60 so that if fits in the adaptor without binding up so that must weaken it a fraction i guess.
Its not much you cut off though and i personally prefer that over taking the 4L60 in bits to swap the output shaft.
The D300 is a far quicker and simpler alteration to someone who shudders at the thought of disassembling the auto but you may think different.

Are you planning on using the D30 on the front? i had hours and hours of fun trying to get the front prop shaft to clear the 4L60.

 

[mysunnshine]

Are you planning on using the D30 on the front? i had hours and hours of fun trying to get the front prop shaft to clear the 4L60.

^^^ This is the big problem....

 

[Kane]

I have scout Dana 44 axles and the dif sits further out than the Dana 30. I think this will give me the clearance I need.

 

[Ron84cj]

I will recommend that you use the original ECU because it has good logic in it and a replacement harness is only about $600.

I agree with this completely. Whether you rework the original harness or buy a new factory one, they are very easy to deal with. The factory ECU does well too.

 

[mysunnshine]

I agree with this completely. Whether you rework the original harness or buy a new factory one, they are very easy to deal with. The factory ECU does well too.

The issue with reworking an original harness is the wiring and all of the connectors are very brittle. I'd rather start with a new harness and connectors that runs the ECU off of the rear of the engine instead of the drivers side front area. That is my preference though.

 

[Kane]

The issue with reworking an original harness is the wiring and all of the connectors are very brittle. I'd rather start with a new harness and connectors that runs the ECU off of the rear of the engine instead of the drivers side front area. That is my preference though.

The aftermarket harnesses route to the back? That would be much cleaner for the install.

 

[ag4ever]

The issue with reworking an original harness is the wiring and all of the connectors are very brittle. I'd rather start with a new harness and connectors that runs the ECU off of the rear of the engine instead of the drivers side front area. That is my preference though.

What brand harness or source do you recommend?

 

[mysunnshine]

We have been using PSI for about 8 years now with no issues. https://www.psiconversion.com/

The aftermarket harnesses route to the back? That would be much cleaner for the install.

I agree. That is one of the few reasons that I do not like using the factory harness.

 

[Kane]

We have been using PSI for about 8 years now with no issues. https://www.psiconversion.com/



I agree. That is one of the few reasons that I do not like using the factory harness.

$579 is not a bad price to have a clean new harness with proper routing. I think this is worth it.

 

[Randyzzz]

You might consider a pass drop 241C case. My build has one with a JB SYE and an AA clocking ring. I have clearance with a stock D30 so it should be perfect with a D44. Lots of pics in my build thread.

 

[Kane]

You might consider a pass drop 241C case. My build has one with a JB SYE and an AA clocking ring. I have clearance with a stock D30 so it should be perfect with a D44. Lots of pics in my build thread.

I looked at your thread and it is amazing so far. I am going to stay with the Dana300 since I already have it setup for twin stick and I feel since the dana 44 dif sits further out under the frame so I am pretty confident the shaft will clear the pan.

 

[Kane]

I want to run a GM stock in tank pump for my fuel system and was considering modifying one from an early 2000's Suburban. The pump package is just a little taller and I think I can shorten it up to fit in my tank. Anyone have any feedback on this? Maybe another model truck or car that has dimensions closer to the 20 gallon poly Jeep tanks?

 

[sdsupilot]

I ran this in my steel tank. It would be pretty easy to install in a poly tank.

https://www.tanksinc.com/index.cfm/...duct_id=84/category_id=61/mode=prod/prd84.htm

I cut the hole in the tank and installed the assembly. I used their roll over valve as the vent and plugged the rest of my fuel tanks ports. Since yours is poly, I would use the stock roll over valves and vents. Either would be fine though.

 

[Randyzzz]

I want to run a GM stock in tank pump for my fuel system and was considering modifying one from an early 2000's Suburban. The pump package is just a little taller and I think I can shorten it up to fit in my tank. Anyone have any feedback on this? Maybe another model truck or car that has dimensions closer to the 20 gallon poly Jeep tanks?

The later model plastic fuel modules are spring loaded and there’s a range of depths that it will self-adjust to. The hard part is making a proper mounting surface, it’s almost 4” in diameter. I thought about that with a poly tank but first all the tanks I looked at didn’t have a large enough smooth area to work with. Secondly I was concerned about sealing the opening with a flexible poly tank.

 

[jpnmaine]

Tanksinc is the way I will go when I get to that point. Like their product; the video of the mustang conversion shows how straight forward it is...and you get to keep your fuel sending unit.

 

[mysunnshine]

Holley makes a nice retrofit pump kit too.

 

[TravelnMan]

I'm in Connecticut and did this swap awhile ago and then switched the transmission to a 5speed. You're welcome to take a look at it. There are some items I'd do differently if I were to do it again and/or may change at some point in the future

 

[Boomer]

I'm in Connecticut and did this swap awhile ago and then switched the transmission to a 5speed. You're welcome to take a look at it. There are some items I'd do differently if I were to do it again and/or may change at some point in the future

As someone preparing to undertake this, please share.

We really need a general LS swap thread.