Lubegard 63010 Platinum Universal ATF Protectant, 10 oz

If a transmission shudders on the torque converter lockup, runs hot, or you just want a fresh rebuild to live a long life, this is the bottle to reach for. It pours into whatever ATF is already in the unit, works with every automatic fluid on the shelf, so you stop trying to guess which specialty fluid the transmission wants and get the protection either way. One 10 oz bottle treats a normal automatic; add it after a fluid service or a rebuild and let it circulate.

The reason it works is the patented Synergol TMS chemistry. It tightens up the shift cycle without killing the friction the converter needs to lock up clean, which is what actually eliminates that low-speed shudder people chase for months. It knocks down operating temperature, and heat is the number one killer of an automatic, and it keeps the fluid from oxidizing and foaming so the ATF holds up longer between changes. It also conditions the seals and O-rings and frees sticky valves, so a lazy shift often cleans itself up.

It does the job without the junk: no zinc, no ash, and it will not upset the sulfur balance or attack the yellow metals inside the case the way some additives do. Whether you are protecting a high-mile daily, a tow rig that cooks fluid, or a transmission you just put back together, this is the cheapest insurance you can pour in. Ships from the USA.