The ultimate headlight upgrade H4 (not LED or HID)

The high wattage bulbs should not be installed without the harness. You will see little to no gain and a huge load on the factory wiring. The factory wiring is insufficient to provide those bulbs with the power they need, which will result in significantly lower output than their potential at full power with the harness.

 

Without the beefy harness your probably only getting like half the performance of the bulbs at best.

 

Ok. Thanks for the feedback, that’s exactly what I needed to know. I’ll throw the stock bulbs back in until the harness arrives and I install that as well. Appreciate the help.

 

I received the harness and installed it Wednesday evening. The headlights weren't adjusted perfectly and I could see an improvement but not much

Friday evening after work I adjusted the lights against the wall in the parking lot.

It was totally dark by the time I drove home, on low beam it's like working on a job site at night, everything in front of you is lit properly

I switched high beam on on top of a small hill and it lit up the road for about a kilometer.
Roadsigns are really, really reflective when the Osram Hypers hit them.

It is totally worth the cost and installation is easy.

@crashnburn80 really did us a huge favor with this mod

 

In addition to not getting full performance from the high-wattage bulbs, the load you're placing on the truck's factory wiring risks blowing the fuse and overheating the wiring, which could cause a fire.

 

“Technically” the fuse should prevent fire. But running the bulbs long enough will likely heat the wire up enough to raise the resistance to a point where the fuse will blow

 

I'd suggest that you pull the high wattage bulbs out immediately. They draw way too much power for the stock harness. That's why you need the HD harness. Running that many amps through the stock harness will overheat important components - especially connectors - and cause damage.

The other problem that you've already noticed is that because your factory harness can't handle the extra load, light output suffers significantly. Wait until you get the HD harness, then re-install the high wattage bulbs and you'll see a dramatic difference.

 

Headlights were delivered quick from the link in the OP.

 

Not a Tacoma but my 2001 Silverado. Installed new headlights and to show what a difference clear lens will make! I have 9012s installed in the low beams. On the left is the new headlight, old headlight on the right. Both have the exact same bulb. I'd already cleaned up the old headlight with toothpaste and water. BTW the tape marks where where the old lights were focused so I could easily realign the new lights. Oddly enough the new lights came with a shield (not a cap) that surrounds the low beam. The original didn't have any type of shield or cap. The old headlights say "Guide" on them so I don't know if it's the original headlights but since it has belonged to my step father since new, I'm assuming they are. I went with TYC from Rockauto. Seemed to be a reputable brand, not expensive but not the cheapest either. While I was there I replaced the high beams with Wagner 9011s. So far they seem to work very well.

Pardon my dirty garage door.

IMG_20210206_144904

0206211106

 

I know this is a third gen thread, but I’m going to upgrade the harness in my 03. Where and how did you guys mount the relay block?

 

Where are you guys buying the headlights housing from? I have a 2006 TRD sport. not sure if I want the smoked lenses or not. Just looking for the best prices

 

I mounted mine to the inner upper fender rail. Run your wiring for everything first and start looking for a place once you know how much slack you’ll have with the wiring.

 

This is actually a 2nd Gen thread. The Search function should locate 100+ posts about mounting sprinkled throughout.

You may also find the 1st Gen Proper Headlight Upgrade thread useful/informative.

 

Didn’t think this would be a gen vs gen thing. The conversation in the first gen thread is mostly about projectors.

 

Left front fender on my 2014. The large nuts are just spacers.

 

I wanted to use those two threaded holes as well but didn't have any bolts that fitted

Do you know the size and pitch of the bolts you used?

 

@crashnburn80 - so any of the bulbs you've evaluated in here would require a harness upgrade? Apologies in advance if you covered that in your write-ups. I think what @Georgeth1022 and others are wondering is, how much improvement can someone expect without a harness upgrade versus with an upgrade? Top five concerns about harness upgrades probably range from: (5) People who bought their trucks to drive them and are looking for quick fixes that dramatically improve performance, (4) people who are whiny and hate doing electrical work on cars, (3) people are old, grumpy or threw out their backs and can't worm around under the hood like they used to, (2) People who have honey-do lists a mile long, (1) People are concerned a dealer could point at the upgrade and play the evil "voided warranty" card.

 

Sorry, not sure. I just dug through my metric stash until I found a couple that fit.

 

This 3rd gen thread might help if one takes the leap of faith that it might apply to 2nd gen too? Probably ideal to test and confirm with something like those thread checkers. I actually bought a set of thread chasers as the unused spots on the passenger side stripped when I tried to use them, and the upside to the thread chaser tool is that it also serves as a thread sizer tool.

 

Finally took my first run this weekend with the new upgraded harness. What a difference. It definitely took me a little getting used too. I was under the impression that my brights were on because of the extra visibility.