DIY Multipro Tailgate Speaker System

[Mason603a]

For those of you looking to setup your own MultiPro tailgate speaker system, well HERE YOU GO! Wiring harnesses and amplifier brackets to make your project super easy!! No splicing or hacking away at your expensive factory wiring! I have a limited number of the items in stock, 10 or so of each, with more that will be ready next week!

When I did mine, I used the Soundstream ST4.1000DB bluetooth amp (and I am very pleased with it so far), so all of the options are available as plug and play with that particular amp. Or you can just get a harness with a pigtail that will give you 12v+ power and ground in your inner tailgate, so you can wire it up to whatever you want. Don’t forget to check out the options for adding lights and the speaker wiring harness to make the whole system truly PLUG & PLAY. so much better sound than the Kicker system for a lot less money!

All items come with complete installation instructions (with pictures, ha)!

Let me know if you have any questions!  

 

www.multiprorocks.com

 

 

Edited July 13, 2020 by Mason603a
add information

[Coastie]

nice design, nice website, good job!

One thing I couldn't notice in the wiring harness, is there an on/off switch?

[Mason603a]

2 hours ago, Coastie said:

nice design, nice website, good job!

One thing I couldn't notice in the wiring harness, is there an on/off switch?

Thank you!! 
 

there is not an manual switch but there is a tilt switch integrated into the harness that automatically powers the amp on (but doesn’t automatically play music) when the inner gate is fully deployed (down) and automatically powers it off when the gate is folded up. A manual switch could easily be added if someone preferred that. 
 

let me know if you have any other questions! 

[Kyle's AT4]

Do you have a picture with the step closed to show clearance?

Sent from my SM-G973U1 using Tapatalk

[Mason603a]

10 hours ago, Kyle's AT4 said:

Do you have a picture with the step closed to show clearance?

Sent from my SM-G973U1 using Tapatalk
 

The step easily closes without the speaker grills, but I wanted the grills on so i stacked some fender washers in under the step and grabbed some longer screws from Lowe's.

 

[Unwrntd]

this is wicked cool!

[Unwrntd]

Edit: duh you said pictures and instructions are included.

 

next dumb question, does the accessory power need to be on? This is my first sierra and i'm not sure if the trailer power is on when the vehicle off.

 

Evin

Edited July 16, 2020 by Unwrntd

[Mason603a]

12 minutes ago, Unwrntd said:

will you be doing an install write-up?

Yes, should have one done today or tomorrow!

[Mason603a]

1 hour ago, Unwrntd said:

Edit: duh you said pictures and instructions are included.

 

next dumb question, does the accessory power need to be on? This is my first sierra and i'm not sure if the trailer power is on when the vehicle off.

 

Evin

The truck accessory/switch does not need to be on. The trailer power is always hot, hence the need for the tilt switch.

Edited July 16, 2020 by Mason603a
additional info

[Unwrntd]

awesome! i can't wait to install this

[Spyder7447]

Wish i knew where to find this kit as a complete set.  Lol

[shawnmason01]

I am trying a slightly different approach on this. I have a 3D printer, so I have designed replacement panels along with panels that have recesses for the bluetooth controller and an aux port.

Once I get the marine speakers in, I will print panels that have mounts for them as well.

[Drgn_Phnx]

On 3/29/2021 at 3:30 PM, shawnmason01 said:

I am trying a slightly different approach on this. I have a 3D printer, so I have designed replacement panels along with panels that have recesses for the bluetooth controller and an aux port.

Once I get the marine speakers in, I will print panels that have mounts for them as well.

So, any progress or pics? I’ve been trying to reach the OP about purchasing his kit, but no luck. I real want an aftermarket setup

for the tailgate.

[Offroadman00]

On 4/8/2021 at 12:08 PM, Drgn_Phnx said:

So, any progress or pics? I’ve been trying to reach the OP about purchasing his kit, but no luck. I real want an aftermarket setup

for the tailgate.

Same here. Would love to know if anyone has more details about the harnesses to get this working.

[shawnmason01]

I have mine working. I had to reprint the parts with PETG filament to make them UV and sunlight resistant. The first ones warped.

 

I wired in a power switch as there are times I will use the system without the tailgate down (for example when camping and I have my hitch in). I also, just ran a standard amp wiring kit along the undercarriage rather than cutting into or modifying my 7pin connection. The 10 Gauge wire was much cheaper than buying the $90 pigtail.

 

BT Controller - https://www.amazon.com/gp/product/B00WVTS4R4/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

 

4" Marine Speakers - https://www.amazon.com/gp/product/B08P7CKXBD/ref=ppx_yo_dt_b_asin_title_o03_s01?ie=UTF8&psc=1

USB port - https://www.amazon.com/gp/product/B07SWZRFRS/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

 

Wiring Harness and Wire - https://www.amazon.com/gp/product/B08FRRC4RN/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1, https://www.amazon.com/gp/product/B01C7O7Z68/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

 

Power Switch - https://www.amazon.com/gp/product/B07P68NFXZ/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

 

3d Printer STL Files (I printed them with PETG, and only did supports on the speaker mounts).
 

- Speaker mounts (these have a lip the slides under the tailgate metal, is is tightened down when you screw the speakers in https://www.tinkercad.com/things/cYdAZhWyiD6

 

- Blue Tooth Controller https://www.tinkercad.com/things/j6kqISHpcYt

 

- USB Port Panel - https://www.tinkercad.com/things/ldsRsnBkZs0

 

 

Here are the components I used