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Uniden R3 vs. Uniden R4: What’s The Difference & Which One Should You Buy?


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Uniden R3 vs. Uniden R4: Quick Take

As far as which one you should go with, here is what we recommend:

  • When it comes to price: The Uniden R3 is our choice. As of this writing, it retails for about $300 on Amazon. The R3 is the best radar detector in this price range and will quickly pay for itself if you avoid a ticket or two while you own it.
  • When it comes to features: We will opt for the Uniden R4 every time. As of this writing, it retails for about $350 on Amazon. The R4 has a few convenient features the R3 does not, including an Auto sensitivity mode, an Auto Mute Memory function, and a Memory Quota bank.

Let’s take a closer look at each radar detector.

Uniden R3: Affordable & Trustworthy

Uniden R3

Other units are less expensive than the Uniden R3, but radar detectors are usually a “get what you pay for” type of product. The R3 is nice because it’s not nearly as spendy as the R7 or R8, the two at the top of Uniden’s radar detector lineup. And while it’s double the price of something like the Cobra RAD 480i, the R3 is also twice the radar detector in terms of reliability and accuracy. 

Trustworthiness is key when shopping for a radar detector. While no radar detector is immune to false alerts, the R3 keeps them to an absolute minimum. The best part about the Uniden R3 is that when it goes off, I know a real threat is in the vicinity. In other words, it’s a radar detector you can take to the bank when the display lights up.  

Here is a link to my full review of the Uniden R3, but allow me to summarize some of the high points. 

Radar & Laser Protection

The Uniden R3 will alert you to X, K, and Ka radar bands and laser (LiDAR) guns, with the display showing the frequency when a particular radar band is detected. The corresponding signal strength indicator moves from green to yellow, then red, depending on how close you are to the threat. Audible alerts are also issued, with the tones becoming more rapid the closer you are to the radar source.

Beyond the standard radar bands, the Uniden R3 picks up any nearby red light and speed cameras. The R3 will show camera or traffic light icons and the corresponding distance (in feet) to the alert. The R4 does this as well.

All Threat Feature

The R3 will simultaneously detect up to four radar bands and show each of them visually through the All Threat feature in the settings menu. The strongest signal is designated as the priority, showing front and center on the OLED display. Other signals appear in the left corner via a little digital chart. Below this digital chart is the type of radar band, followed by signal strength bars that ascend vertically the closer you get to the source.

The R4 also has the All Threat feature. The default setting for both units is off, but turning it on will give you more situational awareness. Neither the R3 nor R4 has directional alert arrows, but All Threat will at least alert you to multiple radar sources in your immediate area.

Driving With The Uniden R3

Uniden R3 vs. Uniden R4
Available on Amazon

While I live in the Detroit metro, the R3 is ideal if you are in a small town or a rural area. It’s true that some radar detectors offer Bluetooth capability with a compatible smartphone app. That has its advantages as far as receiving real-time alert notifications, but everything is crowd-sourced. That’s great for here in Detroit, or another large city, where there are more people on the app, but in a smaller town, those apps may not have the same value.

If you live in a rural area, there are likely fewer users on those apps reporting the location of different radar bands, traffic cameras, and speed traps. Where I grew up in rural Iowa, there were a few places the local officers always sat (out by the baseball fields and in the Bomgaars parking lot). On a few occasions, they would mix it up and hit you with a ticket if you were not careful. But for the most part, you didn’t need an app notification to know where they were hiding.

In that regard, the Uniden R3 is a winner. You will have the detection range without paying for features you may not use, like Bluetooth. Yet, at the same time, you also won’t have a cheap, chirpy box that falses out and drives you nuts.

Uniden R4: Feature Packed Protection

Uniden R4

The Uniden R4 is built on an all-new platform, giving it an advantage over the R3 in terms of detection range, false alert filtering, and available features. I like the Auto Mute Memory function and Auto Sensitivity mode, as both are convenient while navigating heavy traffic here in Detroit.

This makes the R4 a perfect “set it and forget it” radar detector. 

The R4’s new platform contains two Low Noise Amplifiers to increase the detection range compared to the R3. Likewise, the R4 detects Gatso radar (RT3 and RT4 frequency ranges) used by the latest speed cameras and other photo enforcement devices. In this regard, the R4 offers more protection from more radar sources than the R3. 

These are key differences that justify the $50 price gap between the Uniden R4 and R3. Here is a link to my full review of the R4, but allow me to summarize some of the high points. 

Sensitivity Modes

Like the R3, the Uniden R4 has City and Highway modes. In City mode, X and K band sensitivity is reduced to prevent false alerts, while Ka bands stay at full sensitivity. In Highway mode, all bands go to full sensitivity to give you the most reaction time on the open road. You can further optimize the R4’s sensitivity levels through the Advanced Mode.

The aforementioned Auto Sensitivity mode is speed-dependent, switching back and forth between City and Highway at a pre-set speed. In the settings menu, you can set the R4’s switching point between City and Highway in 5 mph increments between 10 and 60 mph. 

When you encounter a stationary or “fixed location” false alert, the R4’s Auto Mute Memory feature will likely kick in and automatically lock it out. Here in Detroit, I’ve had my R4 lock out a number of false K band signals, from the doors at CVS to the warehouses in the more industrial parts of the city. 

Auto lockout functionality is usually reserved for higher-priced units, like the Escort MAX 360c. The fact the Uniden R4 has this capability for under $400 is a big plus and a major selling point. 

Memory Quota

The R4’s updated platform enables a memory quota feature, which the R3 doesn’t have. Memory Quota lets you set the individual number of Mute Memory and Mark Locations. In total, the R4 can save up to 2,000 points between the two, but you can allocate that one way or another in 50-point increments.

Right now, I have my Mute Memory set at the maximum of 1,750 allotments, meaning I have 250 for Marked Locations. I tend to encounter more Mute Memory locations here in Detroit, so I want the highest allotment possible. However, I could drop that allotment for Mute Memory in 50-point increments if I need more room for Marked Locations.

Driving With The Uniden R4

Uniden R3 vs. Uniden R4
Available on Amazon

Although the R3 is a solid radar detector, the Uniden R4 is really a cut above thanks to its new platform and technical design. If you are a radar detector enthusiast, the price difference will not matter. The false alert filtering is better, and the Ka Segmentation options feel more precise and dialed in once you have them set. Like the R3, the R4 is a reliable and trustworthy unit, just to a greater degree. I still use my R3 on occasion, but I like my R4 better.

The OLED display is also nicer on the R4 and is an improvement over the R3.

Uniden R3 vs. Uniden R4 Verdict

  • Performance & Value Combo: The Uniden R3 gets our vote, retailing for $300 on Amazon. You can spend less on a radar detector, but they won’t deliver the performance of the R3. If you are new to radar detectors and looking to purchase your first one, the R3 is a great choice. 
  • Features & Functionality Combo: With its improved design, the R4 takes the cake for about $350 on Amazon. If you are a radar detector enthusiast or like having the latest gadgets, the R4 will satisfy your sweet tooth. 

Carl Anthony is Managing Editor of Automoblog and a member of the Midwest Automotive Media Association and the Society of Automotive Historians. He serves on the board of directors for the Ally Jolie Baldwin Foundation, is a past president of Detroit Working Writers, and a loyal Detroit Lions fan.