Big 3/4 wire upgrade

Supply and Tools I used.
(8 feet) Positive and (5 feet) Negative cables https://ceautoelectricsupply.com/battery-cable/

(Red Wire) Approximately 5 feet 3 inches length for cable run from alternator to ANL Fuse block. 12” length positive battery post to voltage regulator fuse block.

You can use the remainder of the positive wire for the ANL Fuse block to positive battery post.If you do not intend to not use a fuse block from the alternator to battery the suggested lengths of 5 feet 3 inches will work to attach to the positive battery post.

(Black Wire) Approximately 4 feet from negative battery post to engine block grounding point. 8 inches from negative battery post to OEM grounding point.


(4) 1/4 and (4) 5/16 Eyelets https://ceautoelectricsupply.com/product/2-1-awg-mega-eyelets/
(1) 5/16 and (1) 3/8 https://ceautoelectricsupply.com/product/45-degree-mega-eyelets/
(2) ¾” diameter black and red 4 inch lenght
Heat shrink tubing https://ceautoelectricsupply.com/individual-components/heat-shrink-tubing/
Alternator Boot https://ceautoelectricsupply.com/product/alternator-boots-4-to-0-awg/
3M Electrical tape Black and Purple
Screwdriver
Wire cutter
12 mm socket
10 mm socket
10 mm ratchet wrench
12mm ratchet wrench
Ratchet: Short and Regular
Hammer
Crimp tool
Heat gun
Dielectric grease
Magnet

ANL Fuse Block



Positive Battery Post



Negative Battery Post



Attached is the diagram for reference lengths

 

NorthStar 27F Battery







How to remove (5) cable harness clips

Push down on the tab,



To remove clip from mounting points is to lift on the tabs



Couple items to remove to aid in the big 3/4 upgrade

Remove the 12mm bolt (beige) for the hose mount (I used a ratchet wrench as the space is tight). You have to remove the oil housing bracket which is also the same point where the battery negative is grounded. The bolt is a 10mm bolt on the oil filter housing that hold the bracket (yellow). Easiest way to get to the oil housing bolts is through the drivers side tie rod area using two 12” extensions. The magnet I mentioned is used to retrieve and place the bolt back on the stud when installing it back in. Trust me you will thank yourself later if you use the magnet.

Brown-10mm bolt




Nut on the oil filter housing (removing and installing) Brown is the 10mm nut, Bracket-Yellow, Main harness-Red, Harness clip-Teal.



Next is to access the alternator wires. Remove the panel clips (4 light green) to access the alternator. Unbolt the alternator power as the new positive wire is being ran straight to battery positive post via the ANL fuse block (original wire ran directly to Fuse voltage regulator). The space is limited so I used the short ratchet as it was the easiest way to remove the 10mm nut.





You will have to remove the Alternator, Starter, and Oil pressure sending connector from Fuse box.

 

As you see this is the after installation pictures of the alternator connector (left OEM) and new eyelet, power wire and alternator boot. I put dielectric grease interior of the rubber boots on both.




After all the brackets bolts, nuts and wire harness are removed I pull all the wires to the front/underneath the truck to remove the OEM power cables from the alternator to the fuse box. I wanted a clean OEM look, since the OEM alternator terminal is too thick to add another terminal on top of it. The OEM had to get removed. You can cut the OEM terminal and add another thin terminal but I rather not mess with the OEM cables. Yes I did it the hard but correct way. Wire identification. Red-Alternator to + battery Post, Small Magenta-Starter connector wire that is going to be part of the main connector harness, Big Magenta- Starter that connect to + battery post, Blue-Oil pressure sender connector, Green is the cables going to alternator.



Wire Identification areas Voltage regulator- small and medium Red, Main harness(Alternator, Starter, and connector harness), Alternator, Starter, Oil connector harness securing point-Purple)



Wrapped up and ready to run to battery and fuse panel. Place all the Harness Clips back into it specific places. The only odd color clip is gray which is for the ground wire from the engine block to battery negative post.



Harness clips-Teal, Alternate positive and connector wires-Red. Starter positive and connector wire-Megenta, All wires in loom- Orange, Oil pressure sender connector-Blue.



Run the Main harness to back of Oil Filter Housing –Orange. At this point do not install the bracket-Yellow and 10mm bolt-Brown until you run the harness up the to the next harness clip then to fuse box and to battery. Confirm the lengths are adequate before you install the bracket(1st) , Ground Wire, and then bolt.





After the run here is the next harness point (screw driver area)

 

Now that you have the Main Harness-Orange ran up to the Fuse and Battery the next step is to mount the Ground-Black. The eyelet I used was the 45 degree to keep the wire from resting on the engine block. Harness Clip-Teal on back of the Oil Filter Housing. Route the Ground wire up towards the battery negative post via the harness clip. Now install the Oil Filter Bracket- Yellow ground wire and (2) 10 mm nut (engine block and oil filter housing). Do not forget the 12mm nut on the hose bracket at the front of engine.




Now I secured/installed all cables. Voltage regulator in the fuse box-small and medium Red, Alternator- Large red (ran to ANL fuse then into battery. Under the black boot (blue cable) is the cable power for the Audio System cable, Fuse Voltage Regulator cable (OEM), and the Starter positive cable.
Grounds: Negative post to Engine bay panel-Small Black. Engine Block to Negative post-Large Black.
Connector Wires-Purple from the Alternator, Oil pressure sender, and starter connector.






There is another ground point on the passenger engine bay near the air filter-green to complete the BIG 4.



Lastly, tape the cable identification label and add zip ties to secure the ground and main harness together. Reinstall the clips on the passenger gap guard after multimeter OHMS test is complete.

.


I hope this helps someone wanting to do the big 3/4 upgrade.

 

Really nice and clean setup!
How does the 27f fit with the oem mounting bracket?

 

Well done. Very well done. Now can you do my truck.........................

 

Took a lot of patience as there is not much wiggle room length in regards to the wrapping of all the wires in the loom. I taped, removed and adjust the lengths of the connector wires 3 times. That's why I posted a PDF diagram to reference the lengths so others do not struggle. The 27F fits the tray and bracket.

 

Great write up! Nice visuals and clean pictures. Good job Joe!!!!

 

Thanks, I joined this forum to learn and also contribute.
One additional lesson to pass on, do not be overly aggressive moving the battery because the headlight light adjustment housing is very close. I bumped the housing hard enough that I had to remove the headlight to JB weld the stationary tab.

 

I scanned thru this but i guess i missed it. What did you just do and why did you do it?

Thanks Tony. Dont know if your serious or laughing. But im good either way. There is some info missing here.

 

Here you go. Why people upgrade their system wires. https://ceautoelectricsupply.com/wp-content/uploads/2016/05/The_Truth_about_the_Big_3_Upgrade.pdf

 

Wouldnt it be easier and cheaper to install a high output alternator??

 

Easier maybe: It requires removal of parts and fiddling just to remove the alternator. The power wire (size) gauge that I had installed is bigger than the OEM. Cheaper No

 

How many wires are you replacing?

 

TOYOTA MOTORS is who you need to sell this idea to.

 

4, it is routed from the alternator directly to Battery now. OEM setup was from the alternator to the fuse box then to the battery.

 

OEM wiring was set to match the stock electrical system.
I have modified it to maximize the alternator and battery performance/ efficiency. In the mean time the OEM alternator works for the amp draw demands of my current upgrades.

 

Sorry to ressurect an old thread, but wanted to say thanks for the awesome write up! How long did this take? Just wondering how much time to set aside to get this done. Also are these lengths and this write up still similar for a 2018 CM? THANKS AGAIN!

 

Great information here with lots of detail. Thinking about doing this with some 2 gauge OFC wire I have left over.

But I can’t seem to find a answer anywhere; does anyone know the stock wire gauge that is used from alternator>fuse box? It looks like 4 gauge, so making the jump to 2 gauge doesn’t seem justifiable. Anyone? Thanks!

 

I'm thinking of doing this at the time of battery replacement. Thanks for the right up OP.

 

So you ran a new 0 gauge from alternator straight to the battery, then battery to the fuse box? Oem is ran from the alternator to the fuse box correct?

 

Correct

 

i know this is an old thread but it's the only here that describes this. been trying to wrap my head around it all afternoon. the ground in your picture above is not part of the wiring diagram you drew. correct? do you remember how long this passenger side ground is?

i'm looking at doing this with 1/0 wire so i can eventually throw in a 250amp alternator. i also need longer cables than the factory ones to make my dual battery setup viable.

 

That passenger side one is short maybe 12-14”. This is it next to the upgraded one I made.

 

Here it is installed

 

rad. thank you. you made the new one very clean. hoping mine will be the same.

 

ack. i've missed something. the wire that was connected at the small red dot on the fuse box, where does it go? thought i was being careful and remembering where everything went but...

 

After the upgrade the wire (small red dot) receives power directly from battery.

Originally. The (small dot) wire was Hook directly to/from the alternator.