Ultra-low-viscosity full synthetic ATF meeting DEXRON ULV and MERCON ULV for Ford 10R80 and GM 10L80 ten-speed automatics. One gallon.
Shopping for ultra-low-viscosity fluid for a 2019-up Silverado 1500 or Sierra 1500, a Tahoe, Yukon or Escalade on the GM 10L80, or an F-150 or Expedition on the Ford 10R80? Hot Shot's Secret Green Diamond ULV is a one-gallon jug of 100 percent Group III synthetic ATF that the maker recommends for vehicles calling for GM DEXRON ULV, Ford MERCON ULV (WSS-M2C949-A) or Mercedes-Benz MB 236.17. It is the fluid to look at when a 10-speed has started to shudder at light throttle, cycle the converter clutch on the highway, or shift late and hard until it warms up.
The 10L80 is a clutch-to-clutch ten-speed with no bands and no dipstick. Fluid is the hydraulic medium for every clutch apply, the friction surface for the converter clutch, and the coolant for the whole unit. GM designed it around a fluid much thinner than older grades: Lubegard's comparison puts ULV near 4.5 cSt at 100 C against 5.95 cSt for DEXRON HP. The TCM learns clutch fill times on that thickness, so a heavier fluid makes every fill event late and the adapts spend their time chasing it. Green Diamond adds the brand's FR3 additive on top of the synthetic base to hold friction behavior steady as the fluid heats and ages.
Fluid fixes friction and level problems, not hard failures. Scan for codes first: stored solenoid or pressure faults point to the valve body, and GM's recall on this unit was about valve body wear, covered in our 10L80 valve body recall guide. If the codes are clean, check level and condition the way GM specifies. Our 10L80 fluid type and capacity guide walks through the pan fill tube and the 75-80 C check window. Wet case seams or cooler lines mean a leak, and the 10L80 leak guide shows where to look.
This listing covers the GM 10L80 and 10L90 and the Ford 10R60 and 10R80, the units the maker names for this fluid. Do not judge by the vehicle alone: some trucks in the same model year shipped with a six- or eight-speed that takes DEXRON VI or HP instead. Read the spec printed in your owner's manual. If it says DEXRON ULV or MERCON ULV, this is the right class of fluid. If you are unsure which unit you have, send us your year and VIN before ordering. GM's own documents call for its DEXRON ULV by part number, so if the truck is under a powertrain warranty keep receipts that show a ULV fluid went in. All of our ten-speed parts are on the 10L80 parts page.
GM lists 8.1 quarts for a 10L80 pan and filter service, 11.6 quarts for an overhaul and 13.23 quarts including the cooler. One gallon covers a simple drain-and-fill; a pan, filter and full refill needs a second jug. Fill from underneath through the pan plug with a pump or filler adapter, since there is no fill tube. Ignore the CAR and TRK plugs on the side of the case; Transmission Digest notes they are for factory use and sit lower than the pan level tube. Set the final level at 75-80 C with the engine running. Above 80 C the unit reads under-filled, and below 75 C it reads over-filled. Run an adaptive relearn afterward. If the fluid came out with clutch material or the shudder stays, the next step is usually a 10L80 valve body or a 10L80 solenoid kit, not more fluid.
| Volume | 1 gallon (128 fl oz) |
| Base oil | 100% Group III full synthetic |
| Specifications | DEXRON ULV, MERCON ULV |
| Additive | FR3 friction reducer |
| Fitment | Ford 10R80 and GM 10L80 ten-speed automatics |
No. It is an aftermarket synthetic that Hot Shot's Secret recommends for vehicles requiring DEXRON ULV, MERCON ULV or MB 236.17. The dealer fluid is GM's own licensed product. Both are ultra-low-viscosity fluids for the same transmissions; check your manual and warranty terms if that matters to you.
For a basic drain-and-fill, usually yes, because only part of the 8.1-quart service capacity drains out of the pan. For a pan and filter service with a full refill, order two gallons. A dry unit after a rebuild takes about 13 quarts with the cooler.
No. Those units were calibrated for a thicker fluid. Putting ULV in a DEXRON VI or Mercon LV transmission can cause soft or slipping shifts. Use it only where the manual calls for a ULV specification.
It can if the shudder comes from worn-out or wrong fluid, since the converter clutch depends on the fluid's friction behavior. It will not fix a worn valve body, a failing solenoid or damaged clutches. Scan for codes and look at the old fluid before you count on a fluid change.
It is recommended. The TCM has learned clutch fill times on the old fluid. Running the adaptive relearn with a scan tool after setting the level gives smoother shifts sooner than waiting for it to relearn while you drive.
