Make your own underhood light with Rock Light LEDs

I used to have a strip LED on top of my hood wired down to a hood switch. This was sufficient but I wasn't super happy with the color temperature and I was always worried about the adhesive coming off and ending up in my radiator fan. I've noticed there are some highly priced kits using rock lights. As a DIYer I knew I could do better for less.

I picked up a 4 pack of rock lights off Amazon for $30. I only needed two but I have some ideas of the other two. Two packs are available. Technically $15 for this project.

$19 4 Pods LED Rock Lights, Ampper Waterproof LED Neon Underglow Light for Car Truck ATV UTV SUV Offroad Boat Underbody Glow Trail Rig Lamp (Blue)

https://www.amazon.com/gp/product/B01H7FGFCW/

Next I got a pack of M5 well nuts. These mount into a hole and expand when you tighten. These are perfect for the drain holes in the hood. I paid $12.99 for a pack of 25, I guess they are up to $16.99 now. Only needed two. $1.04

$18 25 Rubber Well Nuts M5-.8 .554 Length 3/8" Hole

https://www.amazon.com/gp/product/B0040D2P7E/

Next I got a stainless M5 SHCS. You need one that's just about as long as the bolt through the light and the length of the well nut. This one is M5 x 18mm.

Start the well nut on the light but do not tighten, just flush it up with the light.


Insert the well nut into the hole, orient it the way you want the cable exit.


Hold pressure against the well nut and tighten the screw until tight. This is where you need to be very careful that your screw isn't so long that it crashes into your hood.


Wire up the rest of the system as all the other under hood light how-tos show. Red wire goes to the battery and the ground goes to the switch on the chassis down by the headlight.



The only negative with this is that the lights don't point straight down. However I am 3D printing a little bracket that will mount the lights pointing straight down. And the bracket will mount into the drain hole on the hood instead of the the rock light. I will update with photos once I finish the mounts.

Mount:


Light distribution is pretty good considering half the light is pointing out instead of down. Excited to see how it looks with the brackets.


Update 05-29-2020
Ok was able to test out the first prototype brackets today, they work great! The material will be fine, but I’ll update in a week. I should have 10 sets of the universal mount next week sometime if anyone wants a pair. Just hit me up.

I will get a night shot later tonight, but light distribution should be much better with the lights pointing down.






Night shots:



And before the angled down brackets you can see the lights are basically shining in your eyes:


These lights are much brighter and much truer color than the LED strip light I had before.

If you are interested in the brackets, I have a universal design that mounts the Rigid/Amazon light or the KC Cyclone. Price is $26 shipped for a pair. Let me know if you're interested and I'll add you to the list:

1) @Taco-Obsessed PAID
2) @2012TacomaGuy PAID
3) @GonzoQuick PAID
4) @boogie3478 PAID
5) @Sideways1 2x PAID
6) ^ #2 for Sideways1 PAID
7) @304_Taco (3rd Gen) PAID
8) @sliderule01 (3rd Gen) PAID
9) @Shayde PAID
10) @LC7 PAID

Second batch:
11) @siniquezu PAID
12) @Hemlock76 PAID
13) @Rooster OG (3rd Gen) PAID
14) @DarthR2D2 (3rd Gen) PAID
15) @Gus87 (3rd Gen) PAID
16) @PitCh0w (3rd Gen) PAID
17) @woodsman117 2x PAID
18) ^ # 2 for woodsman117 PAID
19) @sbl23 (3rd Gen) PAID
20) @dwillhere1 (3rd Gen) PAID
21) @Shadowhunter PAID
22) @TheCubicleDaydreamer (3rd Gen) PAID
23) @fishing4boulders (3rd Gen) PAID
24) @norvegicus PAID
25) Local Sale.

Third batch:
26) @TeXanTRD PAID
27) @Crow Horse PAID
28) ^ # 2 for Crow Horse PAID
29) @RedTaco68 PAID
30) @Unchained 5150 PAID
31) @kaijac03 PAID
32) @dk_crew PAID
33) @TheTacoAbides PAID
34) @deanosaurus PAID
35) @telemonta PAID
36) @Unaverage_Taco PAID
37) @Khoadattran PAID
38) @NavyDiver72 PAID
39) @LMarshall73 PAID
40) @GaryLaurenLogan PAID
41) @Tacodog PAID
42) @skylerSurf PAID
43) @rangergs007 PAID
44) @taco lover 65 PAID
45) @Nubes PAID
46) @Josuetobar PAID

Fourth batch (pre-pay):
47) @lizoid PAID
48) ^ # 2 for lizoid PAID
49) @Just84 PAID
50) @deputyduy21 PAID
51) @Puppypunter PAID
52) @Fergmyster PAID
53) @CO MTN Steve PAID
54) @Glockster22 PAID
55) @TacoSherm PAID
56) @Roofy PAID
57) @myTacoma.27 PAID
58) @vorkuta775 PAID
59) @ebrown82 PAID
60) @MICA 808 PAID
61) @Emanresu PAID
62) @dtwomou PAID
63) @WifesTaco PAID
64) @mac84 PAID
65) @VicNic3 PAID
66) @cemented PAID
67) @HandOfGod PAID
68) @KingTaco81 PAID
69) @Airborne22 PAID
70) @Erikerowley PAID
71) @6seven1 PAID
72) @Skatinfool PAID
73) @2010TxTaco PAID
74) @Noeltrd59 PAID
76) @Landpirate PAID
77) ^ # 2 for Landpirate PAID
78) ^ # 3 for Landpirate PAID


Waitlist (not sure if next batch happening):
79) @jarebear74
80) @JasonLee
81) ^ # 2 for JasonLee
82) @BuzzMor
83) @Midship909
84) @ianGP
85) @sf.larry
86) @Sl3ven
87) @Salty_Dog
88) @TacomaOH
89) @Yamahafast
90) @Cbaxter617
91) @Squirrel13
92) @79CHKCHK
93) @dmrivera78
94) ^ # 2 for dmrivera78
95) Jason (email)
96) @#NEVERGIVEUP
97) @audiopudding
98) @TacO1O
99) @elmontemike
100) @Uthmoelleri
101) @FastEddy59
102) @daveeasa
103) Robert (email)
104) @Taco? Who knows
105) @lizoid
106) ^ # 2 for lizoid
107) @mac84 (Single Bracket only)
108) @Dr3w
109) @TacoBlacko12
110) @rb9228
111) @Jahjahsoljah
112) @25TacomaDCab25
113) @Gunerbey
114) @Tacoma_702
115) @BlkTaco20
116) @esgar18
117) @LitFuse
118) @big42mac
119) @shleppy
120) @Chuy21
121) Charles (email)
122) @flatt-taco15
123) @tmzphoto
124) @Camel89
125) @Sirnick88
126) @taco_OnTheMove
127) @pearing


Universal Mount:


Update 06-04-2020:
Alright, the new universal brackets are ready to ship! These work with the KC Cyclone or the Amazon/rigid lights. $26 shipped will get you a pair of brackets and mounting hardware. I have 10 pairs.

PM me for PayPal info.

 

Dang! Looks good! I'm interested in how those 3D brackets turn out. This may be something I do as I'm sick of working on the truck with a headlamp on

 

^I’ll keep you posted, probably another week or so.

light distribution is pretty good considering half the light is pointing out instead of down. Excited to see how it looks with the brackets.

 

very nice. where exactly did you mount the switch?

 

Sub, for results of brackets

 

Down by the headlight, I’ll have to find a link to this switch PN, bought them a couple years ago. The black wire goes to this switch, when the hood closes it opens the circuit.

 

If looking for an ultra high performance light for the project, the answer is the KC Cyclone followed by Rigid's rock lights. Data for the best performing rock lights is here:
https://www.tacomaworld.com/threads/the-led-rock-light-showdown.612253/

 

Interesting, thanks. The rock lights I used look to be an almost exact copy of the rigid, at 1/10th the price. Not sure how light output compares. Not sure I want to spend 10 times more to find out!

The KCs seem like a good alternative though. Although at this point I’m pretty happy with the output of these.

 

Does anyone have a KC Cyclone they can send me dimensions of? I'm going to draw up a mount for that one as well. I just need the overall diameter of the light and the size of the bolt used for mounting. Maybe @crashnburn80 ?

Thanks.

Edit: Nevermind, everything is on their website!

 

You going to sell these mounts? A little side hustle and TW pay it forward?

I like this idea. I saw a post about someone doing this recently that I commented on (yours maybe?). I plan on running these with rock lights in the regular locations. Then add that hood switch like yours just to the hood ones. I like the idea of all rock lights being on giving light around the sides of the truck when the hood is open, but if driving off road with rock lights on when the hood is closed the hood lights would be off.

 

I have not decided yet. If there is enough interest I may sell them, but there isn't much margin and I'm not really looking to make money off TW. Would probably need 10 people for each flavor to make it feasible. I might just share the CAD design and let people order/print them themselves. They are pretty simple designs.

Rigid/Amazon Mount:


KC Mount:

 

Unfortunately there isn't much of a price break for 3D printing at quantity. But seems like I can get them made for about $15/ea, so $30/pair, then add a couple bucks for shipping. This would be my cost, no profit.

If 10 people want to sign up I can make it happen. Won't matter which flavor you want as long as there are at least 10 orders total.

Let me know if you're interested, I'll update the first post with usernames.

 

How do you guys feel about a universal mount that could mount either light? This design is actually a little cheaper to build. Would be $25 shipped for a pair.

 

I'm in.
Looking forward to your finished product and proof of concept.

 

I'll add you to the list for now!

 

I'm in!

 

@Dex__43

 

The engine bay heat has been a issue for me (and it not summer yet) so mounting locations make a slight difference but I’m still testing.

 

Nice write up!

 

What issue is the heat causing? These are never running while the vehicle is operating, only parked with the hood open.