Sure Cool System Upgrade STL010

Works perfectly, lowered temp a good 40 degrees. Super easy to install.

Installation was tricky for me but,... simple enough to accomplish. My transmission temps gave been lowered between 60-90° from high to low ambient temperatures. In warmer weather I was getting 191-197° in traffic and now it is running 100-112° in cold weather and 120-136° in warmer weather. It Works. GET IT, INSTALL IT.

This was not that hard to install, transmission running 30 degrees cooler now, good value for the money

I was running 200-220F hot summer temps (Florida) when I bought my 2018 5.3L Suburban high-mileage used in 2021. I did see a reduction into typical 190s temps, maybe breaking 200 on hot days with a lot of shifting, after doing a fluid evac and replacement. But this device is the REAL DEAL that dropped my temps. I can't get the thing to go over 170F NO MATTER WHAT I DO. Now, because the fluid is running through the cooler CONSTANTLY, it only gets anywhere above 155F if I'm sitting in traffic on a hot day and moving slowly without much air reaching the trans cooler. But as soon as I'm back up to speed, especially highway speeds, the temps start dropping and it's not unusual to cruise at just below 150F on the highway with good air flow. I am 100% certain I have just saved, or at least prolonged, the life of my torque converter. If you have a 6L80 this is as important a thing as you can do for it, and it only takes half an hour with extremely basic tools. Most complicated thing you need is snap-ring pliers that squeeze together (not the one that expands). This is every bit as important with these trucks as an AFM disabler to preserve your lifters, and, frankly, this is a more certain fix than the AFM disabler offers. GM has acknowledged that 190-220F is way too hot for your torque converter in a TSB release, but their "fix" is another thermostat that can freeze shut. This fix allows flow even if everything inside the device fails - the default is open flow to the cooler and worst case, in very cold climate in winter, you might need an extra couple minutes of morning warmup. In most of the country, you just leave it so that it's always open - the check-ball lets it clear out any overpressure from one side or the other so there's no harm that can occur. Just a BRILLIANT solution!!! BTW, my PHOTO shows the HIGHEST TEMP I have been able to reach since installing, and driving in warm weather - average daytime outdoor temp here is 80F. To get it up to 169F as shown in photo I had to run it at high revs in 1st gear in stop-and-go city traffic on a blistering day. That's the max I can get it up to now, and it takes a lot of trying! As soon as I hit the highway, or just 45mph in the city, that temp backs down into the 150s quickly.

I'll tell you that the temps on my 2018 Silverado 5.3, 6 speed trans temps are now safe. 160° or lower. Install was easy. Pushing bypass valve in, even soaked with trans fluid was tougher than I thought it would be. So this means the seal is tight.

Easy to install for anyone who changes their own oil. Straight forward directions. Changed my normal operating temperature on my 2014 GMC sierra 1500 with the 6l-80 transmission from 197° to 147°.

Excellent kit, easy to install and works exactly as advertised. However I wound up replacing it with the revised thermostat from GM (TSB: 21-NA-199) after just 6 months of use due to the transmission being overcooled in the winter and not reaching proper operating temperature, even on long highway trips due to the bypass valve being constantly open. It’s the same issue with the “pill flip” mod on the original tbv. This is no fault of the bypass kit as it works exactly as advertised. But if you are somewhere that the ambient temperature gets below 50°F regularly I would recommend against it as your trans temps will never break 100°F in the colder winter months, especially if you are below freezing for any stretch of time. In those cases I would recommend the updated GM part with the 158° full open thermostat. On hot days my temps never get above 145°F on the updated GM part, and in sub freezing conditions it easily warms up to 110-120°F where the STL kit would keep the transmission below 99°F even with hours of operation. If you are in Texas or Florida or somewhere it’s fairly warm year round this kit should do just fine for you. Easy to install and instantly reduced my operating trans temps from 200°+ to sub 130° on hot days.

This is a great product. It really does keep my teams temps down and it really stays low on the interstate. It works well around town as long as I’m moving. Being in non-moving traffic right behind other hot vehicles, the trans temp will still get up there, but it will go back down as soon as you start moving. The temp also moves up a lot slower than before. The install was super easy, just watch the videos on how to do it, super easy. This little $40 product is well worth it when compared to replacing your transmission. Also a good thing to replace the OEM torque converter when your mileage gets up there or if the trans is acting up. I noticed on my first and second product that the piston and bushing have microsteps in the design. When I put it all together and pressed the piston in, it would get stuck on the bushing every now and again (both in and out). With my first set, my trans temps would still get high every so often. I removed it because I figured it was getting caught and had them send me another for replacement. The second set I received, I sanded down the piston steps and smoothed out the piston edges. That helped out tremendously! After sanding, I can press the piston in without it getting caught on the bushing (going in or coming out). My trans temps also stay lower…except in non-moving traffic. I’m ok with this until I get and install an auxiliary trans cooler. I recommend this for other 2014 and up Silverado owners because you know this is a known issue in our community.

Good

buen producto cumple con su funcion

Does exactly as intended. An absolutely amazing product. Simple to install, directions were very easy to follow and if you need visual help there are many how to install videos on youtube. Took transmission temps from over 100C down to 65-70C and actually improved shifting.

Works great on my wives 2015 gmc sierra with a 6l80e transmission. This is a must for your transmission and is worth every penny. The transmission temperature got really high before allowing transmission fluid to flow through. This deletes the trans thermostat. I used this when I rebuilt the transmission. Keep temp about 30 degrees cooler. The warmer o.e.m temp is too hot and burns up the torque converters the you get the transmission stutter. Great product and easy to install.

Easy install, working great since I bought it, keeps temps 50-60c depending on highway or city driving. Great for towing