AMSOIL Signature Series ULV 100% Synthetic Automatic Transmission Fluid
AMSOIL Signature Series ULV is an ultra-low-viscosity 100 percent synthetic automatic transmission fluid built for the latest electronically controlled multi-speed automatics that call for a Ford MERCON ULV or GM DEXRON ULV service fill, paired with the heat resistance and reserve protection of the Signature Series ATF family.
Engineered for ULV-spec transmissions
Newer Ford and GM automatics use tighter clearances, narrower oil galleries and more clutch packs than the gearboxes that came before them, and they specify a thinner fluid grade than legacy MERCON LV or DEXRON VI to deliver the shift speed, fuel economy and torque-converter lockup behavior the calibration expects. Signature Series ULV is formulated to that thinner grade, with a kinematic viscosity of 4.5 cSt at 100 degrees C (ASTM D445), so the calibration sees the viscosity it was tuned around.
The fluid is approved for service in transmissions calling for Ford MERCON ULV and GM DEXRON ULV. For verified vehicle-by-vehicle application match, look up your vehicle in the AMSOIL vehicle lookup guide before ordering.
Reserve protection against thermal breakdown
Heat is the single biggest enemy of automatic transmission fluid. Signature Series ATF is formulated with high concentrations of antioxidants, which makes the fluid naturally heat resistant and helps it hold off the oxidation that drives sludge and varnish deposits in narrow oil passages and on clutch faces.
In a 180,000-mile severe-service Las Vegas taxi field trial, Signature Series Multi-Vehicle Synthetic ATF retained 83 percent of its original oxidation inhibitors and resisted oxidation in the Aluminum Beaker Oxidation Test (ABOT) longer than the new-fluid threshold required to meet the Chrysler ATF+4 specification. Internal hardware, including the valve body and clutch plates, came out of that trial virtually free of damaging sludge, deposits, and wear. ULV uses the same Signature Series additive philosophy applied to a thinner ULV-grade base fluid.
Wear protection under load
Varying speeds and loads create torque multiplication that puts extreme stress on planetary gears, bearings, and clutch packs. Signature Series ATF is built with high film strength and premium anti-wear and extreme-pressure additives to keep metal surfaces separated during severe service. In the FZG Gear Wear Test, Signature Series Multi-Vehicle Synthetic ATF that had been used for 180,000 severe-service miles still earned a Pass at stage 12, the highest stage in the test, exceeding the new-fluid Ford MERCON V and Chrysler ATF+4 wear thresholds. Signature Series ULV brings that same wear-control approach to ULV-spec hardware and posts a 0.39 mm wear scar in the Four-Ball Wear Test (ASTM D4172, 40 kg, 75 degrees C, 1,200 rpm, 1 hour).
Cold-temperature fluidity
Cold, thick automatic transmission fluid lengthens shift times, hurts fuel economy and slows hydraulic response on the first cycle out of the driveway. Signature Series ULV is wax-free and engineered for extraordinary cold-flow performance, with a Brookfield viscosity of 4,050 cP at minus 40 degrees C (ASTM D2983) and a pour point of minus 62 degrees C, or minus 80 degrees F (ASTM D97). That cold-flow profile helps modern ULV-spec transmissions deliver clean shifts and fast warm-up when ambient temperatures drop.
Friction durability and shift quality
Today's compact automatics have to handle higher horsepower and torque while delivering smoother shifts on longer fluid-life schedules. Signature Series ATF carries a friction-modifier system tuned for clutch-holding capacity (static friction), torque-transfer ability (dynamic friction) and anti-shudder performance in slipping torque-converter clutches. Used-fluid analysis on Signature Series Multi-Vehicle ATF after 180,000 severe-service miles showed friction properties nearly identical to new fluid. Signature Series ULV applies the same friction-control approach to ULV-grade Ford and GM applications.
Recommended applications and service intervals
Signature Series ULV is intended for transmissions and other applications that specify Ford MERCON ULV or GM DEXRON ULV. The fluid is not a universal multi-vehicle ATF; transmissions that call for MERCON LV, MERCON V, DEXRON VI or DEXRON HP should be filled with the AMSOIL Signature Series Multi-Vehicle or Fuel-Efficient ATF that matches that spec. To confirm the correct AMSOIL ATF for a specific year, make, model and engine, run the vehicle through the AMSOIL vehicle lookup guide or compare options in the AMSOIL ATF guide.
- Normal service: follow the vehicle manufacturer's normal-service drain interval.
- Severe service in passenger cars and light trucks: double the vehicle manufacturer's severe-service drain interval, backed by the AMSOIL Limited Warranty.
- Outside the United States and Canada: change at the vehicle manufacturer's recommended drain interval.
- Not recommended for transmissions calling for any ATF specification other than Ford MERCON ULV or GM DEXRON ULV.
For best results, pair every fluid service with a fresh OEM-quality transmission filter and clean any magnets in the pan. Signature Series ULV does not require aftermarket friction modifiers or shudder-fix additives; the additive system is built into the fluid. The fluid is compatible with other ULV-grade automatic transmission fluids, but mixing dilutes the Signature Series additive package, so a complete drain-and-fill or a planned fluid-exchange procedure delivers the cleanest result.
Typical technical properties
| Property | Value |
|---|
| Kinematic viscosity at 100 degrees C, cSt (ASTM D445) | 4.5 |
| Kinematic viscosity at 40 degrees C, cSt (ASTM D445) | 20.5 |
| Viscosity index (ASTM D2270) | 134 |
| Pour point, degrees C (degrees F) (ASTM D97) | -62 (-80) |
| Flash point, degrees C (degrees F) (ASTM D92) | 220 (428) |
| Four-Ball Wear Test, scar, mm (ASTM D4172, 40 kg, 75 degrees C, 1,200 rpm, 1 hr) | 0.39 |
| Brookfield viscosity at -40 degrees C, cP (ASTM D2983) | 4,050 |
Order AMSOIL Signature Series ULV ATF
Signature Series ULV ships in a Quart Easy-Pack (ULVPK-EA), a case of 12 Quart Easy-Packs (ULVPK-CA), a Gallon Jug (ULV1G-EA) and a 55 Gallon Drum (ULV55-EA), so a single drain-and-fill, a complete fluid exchange and a fleet refill order can all use the same fluid. Every package is covered by the AMSOIL Limited Warranty when the fluid is used in the application and at the service interval described above. Confirm application match for a specific Ford or GM transmission with the AMSOIL vehicle lookup guide, then compare against other family options in the AMSOIL ATF guide before placing an order through this site using AMSOIL Signature Series ULV 100% Synthetic Automatic Transmission Fluid.
Customer reviews
Everything is now changed
I have changed everything over to amsoil products. Time will tell me if I have made the right decision. So far Allstars good
By Oscar on July 21, 2026.
Would recommend this to a friend.
GMC Transmission
Driving a GMC I am always aware that the transmission is an issue. But my mind is put to ease using Amsoil. My transmission run 10 degrees cooler than it used too even pulling a trailer since I switched to Amsoil.
By Larry from Calorado on July 20, 2026.
Would recommend this to a friend.
My Honda purr’s
Great stuff, easy to use keeps engine running smoothly
By Luis from Las vegas on July 19, 2026.
Would recommend this to a friend.
Read all 971 reviews
Frequently asked questions
What does ULV stand for in automatic transmission fluid?
ULV stands for ultra-low viscosity. ULV-grade automatic transmission fluids are thinner than legacy LV grades like MERCON LV or DEXRON VI, with a lower kinematic viscosity at 100 degrees C. Ford MERCON ULV and GM DEXRON ULV are the two manufacturer specifications that call out a ULV-grade ATF for the latest electronically controlled automatic transmissions.
Which transmissions use Signature Series ULV?
Signature Series ULV is approved for service in transmissions and other applications that specify Ford MERCON ULV or GM DEXRON ULV. Verify the exact ATF spec for a particular year, make, model and engine in the owner manual or with the AMSOIL vehicle lookup guide before ordering. Transmissions calling for MERCON LV, MERCON V, DEXRON VI or DEXRON HP need a different Signature Series ATF; the AMSOIL ATF guide walks through the difference.
Can Signature Series ULV replace MERCON LV or DEXRON VI?
No. ULV-grade ATF is thinner than LV-grade ATF and is calibrated for transmissions that were designed around the ULV viscosity. Substituting a ULV fluid in a transmission that calls for MERCON LV or DEXRON VI is not recommended. The reverse is also true: pouring an LV-grade fluid into a ULV-spec transmission can affect shift quality, fuel economy, and clutch behavior.
How long can the fluid stay in service?
For normal service, follow the vehicle manufacturer's normal-service drain interval. For severe service in passenger cars and light trucks, the fluid supports doubling the vehicle manufacturer's severe-service drain interval, backed by the AMSOIL Limited Warranty. Outside the United States and Canada, change at the vehicle manufacturer's recommended drain interval.
Does using AMSOIL Signature Series ULV void a new-vehicle warranty?
No. Using AMSOIL synthetic lubricants does not void a new-vehicle warranty when the fluid meets the manufacturer's required specification, which Signature Series ULV does for transmissions calling for Ford MERCON ULV or GM DEXRON ULV. The AMSOIL Limited Warranty further backs the lubricant when used in approved applications.
Do aftermarket friction modifiers or shudder-fix additives need to be added?
No. The Signature Series ULV additive package already includes the friction modifiers and anti-shudder chemistry the fluid is engineered around. Adding aftermarket transmission additives can disturb the friction balance and is not recommended.
