Product Description
Custom Autosound USA-740 IN DASH AM/FM for Buick Roadmaster
The Buick Roadmaster was the big boy of the Buick family. The Roadmaster was built on the longest frame that wasn't a limo, so it was really quite big. I mean when you’re measured against a limo, you know you’re talking one big automobile. The Buick Roadmaster shared some of its platform with its sister Cadillac so you know it was a luxury car at its finest. The long wheelbase meant for a really smooth ride, some said it was like riding on air. The Buick Roadmaster was quite the load so it had to have a torque monster to pull it around.
Custom Autosound USA-740 Classic Car Radio With Bluetooth USA-740 Radio with Bluetooth Features:
- AM/FM Radio Bluetooth, USB & Auxiliary Inputs
- Option to Add CD-1, Single CD Player
- Bluetooth is Built Into the Radio
- Fits in your Original Dash Opening Without Cutting
- 3.5mm Aux Input on Front of Radio
- RCA Aux Input On Back
- Change Display Lettering Color
- Digital Tuner
- RDS Song/Artist Information
- 5 Channel RCA Pre-Outs w/ Subwoofer Control
- Separate Bass & Treble Control
- 5 EQ Presets
- Fader and Balance Control
- 15 FM & 10 AM Pre Sets
- Seek/Scan Function
- Back by a 2 Year Warranty from the Manufacturer
How to combine all this with a great autosound custom-designed radio? At Vintage Car Radio, we have the answer. The USA-740 radio will let the most exigent car collector have the most advanced technological sound system without missing the elegance and originality of such an American classic. No matter how hard you try, there’s no other way to get the best quality sound out of a 1930’s luxury
car such as the Buick Roadmaster. It is definitely a car that deserves better. It started with the big straight eight that weighed a ton but could push the Roadmaster around like it was nothing. Eventually the Roadmaster got the legendary nailhead V8. It was smaller in size but even better at horsepower and torque. The Buick Roadmaster inside was just as nice as it was outside. This is the era that chrome was king and gadgets were everywhere. No matter what the year, the Buick Roadmaster reigned supreme in the luxury car wars.
As good as your classic ride looks, the sound system was lacking. They had speakers and bad radios just ruined a really nice classic ride. Sure in some of your rides you can listen to the hum or cackle of your engine but not everyone has a built up motor (and that can make you cry sometimes). With all that being said, the great people at Custom Autosound have come to the rescue. You have no more worries. They have the top of the line radio and speaker systems that will make your car sound so sweet. Its modern technology wrapped up in a factory appearing package. No one will even know you don't have the stock radio installed! Even better is the installation. Easy-to- follow instructions mean no cutting of your dash. Seriously, if you've ever installed a radio before this will be as easy as riding a bicycle.
Some hidden amenities include:
- Five Presets for the EQ
- Balance along with Fader Controls
The list goes on, but we care about your safety when coming to excitement. Let’s draw out your favorite CDs and let their best tunes join you on the rides you and this kind of classic deserve.
USA-740 IN DASH AM/FM for Buick Roadmaster: Your Questions Answered
Do I need to modify the Buick Roadmaster dash to install it?
This version is built for the Buick Roadmaster and is made to fit the factory radio opening. Custom Autosound says its radios fit without altering or cutting the original dash.
Will it work with a 6-volt system?
Choose your system under Voltage (12 volt and 6 volt) and Ground (Negative and Positive) when you order.
What can the USA-740 do?
Custom Autosound rates it at 300 watts peak, and it adds hi-volt 4-channel RCA pre-outs plus a subwoofer line-out. Bluetooth is built in, with a microphone included, so you can stream music and answer calls.
What else should I know about the USA-740?
There are two auxiliary inputs, a front mini jack and a rear RCA. The USB port plays MP3, WMA, FLAC and WAV files from a flash drive.
Which add-ons are offered with this radio?
The options on this page let you add a front dual voice coil speaker, a rear 6x9 speaker pair (Custom Autosound 6x9 Speaker Pair and Upgraded Pioneer Speaker Pair), and an antenna (Hideaway Antenna and Power Antenna).
Is there a CD or Bluetooth upgrade?
Check the CD options on this page, which include Single Slave CD.
USA-740 specifications
- Bluetooth built in (streaming and hands-free calling)
- 300 watts peak power (45W x 4 RMS, 2-ohm stable)
- AM/FM stereo tuner
- 2 AUX inputs (3.5 mm front and RCA rear)
- USB port
- Direct control for optional CD-1
- 5-channel RCA pre-outs including subwoofer pre-out and control
- 15 FM and 10 AM presets
- 7-color LCD with dimmer; RDS station/song/artist display
- DSP EQ; auto-store presets
- Electronic tuning and volume; separate bass/treble; 4-way fader; L/R balance
- Power antenna lead; digital clock
- USA/EUR/JAP/RUS tuner capability (USA default)
- Custom Autosound 2-year manufacturer warranty
USA-740 wiring and tech tips
Use this as a head-unit reference for power, ground, antenna, speakers, and amplifier connections. Always match the printed diagram that ships with your unit if it differs.
Power and ground (typical Custom Autosound harness)
| Function | Wire color |
|---|---|
| Ignition / ACC +12V | Red |
| Battery / constant +12V | Yellow |
| Ground | Black |
| Power antenna | Blue |
Ignition and power-antenna leads are commonly fused at 1A on the harness—confirm against the guide that ships with your radio.
Speaker wiring (typical)
| Speaker | Wire color |
|---|---|
| Left front + / − | White / White-Black |
| Right front + / − | Gray / Gray-Black |
| Left rear + / − | Green / Green-Black |
| Right rear + / − | Violet (or Purple) / Violet-Black |
USA-740 extras
Expect antenna, USB, microphone (Bluetooth), CD-1, and subwoofer RCA connections in addition to front/rear line outs. Use the front 3.5 mm AUX or rear RCA AUX for wired sources.
Suggested order for a classic Buick Roadmaster
- Disconnect the vehicle battery before any wiring.
- Connect ground first, then constant (yellow) and ignition (red).
- Connect the antenna plug and the blue power-antenna lead if your car has a power antenna.
- Wire all four speakers, matching polarity.
- If using an amplifier, run RCA cables from the front/rear (and sub on USA-740/USA-850) pre-outs.
- Reconnect the battery and test radio, speakers, and charging system voltage.
Tech tips for classic Buick Roadmaster
- This radio is sold for the factory Buick Roadmaster opening used in classic models—do not cut a modern DIN rectangle if you want a stock look.
- A poor ground is the most common cause of whine or weak audio; scrape paint at the ground point and use a star washer.
- If AM reception is weak, check the antenna mast, cable continuity, and that the antenna plug is fully seated.
- Vintage Car Radio does not install radios. If you are not comfortable with 12V wiring, use a qualified installer.
USA-740 manuals
Download the manufacturer guide for operation, safety, and the official wiring diagram. You can also browse our full library on the Manuals page.
Vintage Car Radio does not offer installation. The manuals are for do-it-yourself reference or to share with your installer.
Two-Year Custom Autosound Warranty
All Custom Autosound radios sold by Vintage Car Radio are backed by a 2-year manufacturer warranty from Custom Autosound.
Radios are checked before shipping. If something is wrong out of the box or under warranty, call us at 844-802-4499 or 574-226-6676 and we will help coordinate with the manufacturer.
Vintage Car Radio does not offer installation services. Refer to the Manuals and Wiring / Tech Tips sections for manufacturer guidance, or use a qualified car-audio installer.
FAQ — classic Buick Roadmaster USA-740
Will this fit my classic Buick Roadmaster without cutting the dash?
It is built for the original radio opening used on classic Buick Roadmaster models. Compare your dash opening and bezel to the product photos. We do not modify dashes in-house.
Does this radio have Bluetooth?
Yes—Bluetooth is built into the USA-740 for streaming and hands-free calling.
Do I need an amplifier?
Many owners run speakers directly from the radio. Pre-outs are there if you want more volume or a subwoofer later.
Do you install the radio?
No. Vintage Car Radio ships the unit and documentation; installation is DIY or by a shop you choose.
What is the warranty?
Custom Autosound radios include a 2-year manufacturer warranty. See the Warranty section for details.
Need help?
Call 844-802-4499 or 574-226-6676.
Specs
Wiring / Tech Tips
Manuals
Warranty
Two-Year Custom Autosound Warranty
All Custom Autosound radios sold by Vintage Car Radio are backed by a 2-year manufacturer warranty from Custom Autosound.
Radios are checked before shipping. If something is wrong out of the box or under warranty, call us at 844-802-4499 or 574-226-6676 and we will help coordinate with the manufacturer.
Vintage Car Radio does not offer installation services. Refer to the Manuals and Wiring / Tech Tips sections for manufacturer guidance, or use a qualified car-audio installer.
