Variable Speed Controller and Relay Kit with Thread-In Temperature Sensor, Fan Controller With Temperature Probe (31163), Black

I installed an older version of this in my car over 10 years ago.It was still working fine, but I didn't want to risk overheating, so I replaced it.Since I bought my first one the controller has been redesigned and is much improved.(Not that it was crappy before ;-)The fan speed ramps up and down over about a 10 degree range which is nice.It has a "soft" start so as to be easier on the charging system.Very important to me living in the south:It has a controller lead that can be wired to your AC compressor so that the fan comeson when the AC is running. This provides MUCH improved AC performance comparedto my OEM fluid fan clutch. This feature alone made it worth installing for me!Tech. Support is available. It is speedy and knowledgeable.I spoke with AJ about some details of installing this on my "vintage" 1986 vehicle,and he was incredible helpful!All the parts that you will need are included in the kit, and he fuse block included is the most robust I have ever seen! I've had trouble in the past with the crappy fuse holders from the mass-market parts stores...I expect no trouble from this one!

Great value for the price. This is a quality product and works as described. I have this controlling two 12" Spal fans and works perfectly. I really like the feature that lets the fans continue to run after you shut the car off. The way the controller starts the fans at 60% and ramps up as needed is also a great feature. So much easier on the charging system. I would not hesitate to purchase again.

I called the tech line at Flex-a-lite before I bought it,and told them them I had a Derale two speed fan and wanted to know if it would work on it properly. Tech said it should work fine. (Note: Derale controler I bought was junk, did not work out box and tech support does not exist.) Unit installed fine, but fan chatteres when first starting. I believe this is due to 60 % starting current. The Derale fan is 13 inch in diameter, tried it on both speeds same result. Called the tech line to see if I was doing somethng wrong. Tech was very supportive, went throught installation process seems everything was right. After checking out found that all the connections were creating a lot of resistance. Cleaned the connections and checked with meter and fan only slightly chatters at start up. Controller works very well. Recommend to manufacturer to make leads from controller to battery in one long piece to elimate 2 splices. This will also make it look cleaner.

I normally don't write reviews but I was so please how well this unit worked I had to share with others. I have been struggling to control the heat out here in the Southwest dessert on a modified Classic Mustang, 347 stoker, 3 core aluminum radiator, 2 wire fan. Once I was reaching operation temperatures and my temp sensor signaled to turn the fan on, my carb. would get heat soaked, the fuel would boil and that was the end of the run. This unit not only allows me to control the heat very well within a tight window, it does not let my charging system get overworked, and because of the lower fan speed it does not overload connectors. all win win scenarios. The low cost was more than worth it, Installation was easy. The only thing I didn't care for was that I had to change my connector because I don't like using butt connectors. Now we wait and see how durable it will be??? .

Bought this to replace an older version. Installed in a Jeep Wrangler YJ. Easy install, well built, does its job.

I'm a master certified mobile electronics technician, over 35 years in the custom automotive field, restoration, custom fabrication, and electrical. I've always loved Flex-a-lite products until now. Module was installed on a well maintained 2001 Ford Ranger that still looks like the day we bought it. Decided to relieve the added stress from the factory fan and add my go to Flex-a-lite products. Installation was always straightforward, clean, and installed to look factory. However, the longevity of this unit doesn't leave me comfortable to put anyone behind the wheel with a Flex-a-Lite product. Keeping things cool is not what it's cracked up to be. Where did this go wrong? I can guarantee the installation 100%.... that's my job and my responsibility to provide not only myself but my customers what was supposed to be a quality product. One failure leaves the door wide open for multiple failures. I'm requesting to my customers whom I've installed any Flex-a-lite products to whether they purchased the modules themselves or not to bring them in and swap them for another product. All it takes is one failure, excessive overheating, and a family member stranded in this Texas heat to realize that the quality has gone down hill.Thank you Flex-a-lite for the quality in what used to be years ago, but not where it 's heading today.

it cuts the startup amps by half, this is great fore the charging system

Works great, super simple and straightforward to install. I didn’t bother with the manual on/off circuits, just the A/C kick-on. Came with several fittings to get the temp sensor installed without having to buy anything extra.I’d was hoping for dual output so that you could have each fan start at different temps or only one kick on with the A/C. But since they start up at only 60% I suppose having both come one simultaneously isn’t so bad.The only thing I wish it had was a better means of setting the temp instead of making it a guessing game - simply putting tick marks around the trim pot or using dip switches instead would have been nice.On another vehicle I installed one that had a digital readout and all kinds of settings and adjustments, but all told it was probably double the price and I never really used those features.