Automatic Transmission Fluid is the most technically demanding lubricant after marine cylinder oil — it must simultaneously transmit hydraulic pressure, lubricate gears, control friction at the clutch plates, and cool the transmission. The friction static/dynamic ratio specification is the technical hurdle that filters out most aftermarket formulations. This guide gives the recommended Dexron VI BOM, the friction modifier chemistry, BIS / OEM positioning and Indian brand benchmarks for Castrol Transmax, Shell Spirax, Mobil ATF 3309.
| Component | Function | % (m/m) | Indian Supplier |
|---|---|---|---|
| Group III 4 cSt base oil | Primary base, hydrocracked, VI 130+ | 78.0% | Reliance / SK / Neste Group III via import |
| PAO 4 cSt synthetic base | Low-temp viscosity boost | 5.0% | INEOS Durasyn / ExxonMobil SpectraSyn |
| ATF DI package (Lubrizol 9657 / HiTEC 3441) | DI — AW + AO + CI + dispersant + foam | 5.5% | Lubrizol / Afton India Mumbai |
| Friction modifier (oleamide + MoDTC blend) | Static/dynamic friction control | 0.6% | Adeka Sakura-Lube + organic FM |
| PMA VII + PPD (Evonik Viscoplex 8-225) | Multifunctional VII + pour point | 5.0% | Evonik Viscoplex / Lubechem LC-VII-PMA |
| Phenolic AO (BASF Irganox L57) | Primary oxidation inhibitor | 0.6% | BASF India |
| Aminic AO (alkylated DPA) | Secondary AO synergist | 0.4% | LANXESS Naugalube 438L |
| ASA + thiadiazole CI | Ferrous + yellow-metal protection | 0.4% | King K-Corr + Vanderbilt Vanlube 887 |
| Silicone + non-silicone foam inhibitor blend | Foam control under hydraulic pressure | 200 ppm | Dow Corning DC200 + polyacrylate |
| Seal swell ester (TMP-trioleate) | Maintain elastomer seal integrity | 4.0% | Croda / specialty ester suppliers |
| Red dye (ATF standard identification) | Industry-standard ATF colour | 200 ppm | BASF / Clariant pigments |
| Group III diluent | KV / VI fine-tune | 0.9% | Group III |
| TOTAL | 100.0% | — | |
Process: blend Group III + PAO at 70 °C with low-shear; charge DI package and seal-swell ester; dose PMA VII slowly at 65 °C; add FM, AO, CI; foam inhibitor blend last with 5-min mix only; final red dye. QC: KV100 6.0-6.4 cSt, VI ≥150, pour <-50 °C, foam D892 Seq I <25/0/0, friction static/dynamic 0.92-1.05 (SAE No.2 friction machine). Ex-works cost ₹150-220 / L at 5 MT batch. Pack in 1 L can, 4 L jug, 200 L drum.
| ATF Family | OEM | KV100 (cSt) | Critical Spec |
|---|---|---|---|
| Dexron VI | General Motors | 6.0 | Static/dynamic friction, shear stability |
| Mercon V / LV | Ford | 5.7 / 5.5 | Low-viscosity, fuel economy |
| ATF+4 | Chrysler / Stellantis | 7.5 | Anti-shudder, lifetime fill |
| CVT — Honda HCF-2 | Honda | 7.0 | HIGH friction (opposite of ATF) |
| CVT — Nissan NS-3 | Nissan / Maruti | 7.2 | HIGH friction, steel-belt grip |
| DCT — VW G 052 182 | VW / Audi / Skoda | 5.5 | Dual-clutch friction, oxidation |
Automatic Transmission Fluid (ATF) is the specialised hydraulic + lubricant + friction-modified fluid used inside automatic, CVT and DCT transmissions. It must do four jobs simultaneously: transmit hydraulic pressure, lubricate gears and bearings, provide controlled friction at the clutch plates, and cool the transmission.
Major families: GM Dexron III / VI, Ford Mercon V / LV, Chrysler ATF+4, JASO 1A (Japan), CVT-specific (Honda HCF-2, Nissan NS-3), DCT-specific (VW G 052 182). Base oil Group III / PAO synthetic, KV100 5.5-7.5 cSt, friction modifier critical.
Dexron VI ATF BOM (%): Group III 4 cSt 78%, PAO 4 cSt 5%, ATF DI package 5.5%, FM (oleamide + MoDTC blend) 0.6%, PMA VII + PPD 5%, phenolic AO 0.6%, aminic AO 0.4%, ASA + thiadiazole CI 0.4%, foam inhibitor 200 ppm, seal swell ester (TMP-trioleate) 4%, red dye 200 ppm, balance Group III diluent.
KV100 6.0-6.4 cSt, VI 150+, pour <-50 °C, friction static/dynamic ratio 0.92-1.05 per GM Dexron VI spec.
Dexron III (legacy 1993-2005) used Group I/II mineral base with conventional FM. Acceptable for older GM, Ford, Chrysler automatic transmissions through 2006 model year. KV100 ~7.5 cSt, VI ~150. Dexron VI (2006-current) requires synthetic base, tighter friction modifier balance, longer drain, better shear stability.
Dexron VI is backwards-compatible (works in older Dexron III transmissions) but Dexron III is NOT forward-compatible. Modern blender produces only Dexron VI for new market.
ATF clutches engage via wet-friction discs — paper-fibre disc against steel reactor plate, lubricated by ATF. Friction profile matters: too high static friction → harsh engagement; too low → clutch slips. FM tunes static/dynamic/slip friction balance.
GM Dexron VI specifies static:dynamic friction ratio 0.92-1.05 — outside this range the transmission shifts harshly or slips. FM represents the highest-stakes additive in ATF formulation. Getting FM right is the technical hurdle for new ATF formulations.
CVT (continuously variable transmission) uses metal-belt-on-pulley friction transfer — opposite friction requirement: HIGH friction needed for belt-on-pulley grip. CVT fluid (Honda HCF-2, Nissan NS-3, Toyota TC) uses high-friction-stable additive package. Wrong fluid in CVT causes belt slippage and immediate damage.
DCT uses two parallel clutches that pre-engage — needs ATF-like friction profile plus better cooling and oxidation life. Mercedes 7G-DCT, Audi/VW DSG use DCT-specific fluids (G 052 182, MB 236.21). Each fluid family is incompatible; blender must produce SKU per family.
India ATF market: 4W aftermarket dominated by Maruti Suzuki (NS-3 CVT for Baleno/Brezza, ATF SP-IV for older Vitara), Hyundai (ATF+4, DCT for Verna/Creta), Tata Motors (Castrol Transmax for AMT), Mahindra (Dexron III for older XUV).
Brands: Castrol Transmax Dexron VI / CVT / DCT, Shell Spirax S6 ATF, Mobil ATF 3309, Total Quartz ATF, IOCL Servo ATF, BPCL Mak ATF, HPCL ATF. ₹240-580 / L retail. Lubechem custom (LC-ATF-DEX-VI) ex-works ₹150-220/L at 5+ MT batch.
BIS IS 17073:2019 covers ATF (Dexron II/III equivalent class). Newer Dexron VI / CVT / DCT specs are OEM-licensed (GM, Toyota) and not directly covered by BIS — Indian blenders must qualify against the OEM specification at the OEM's authorised lab (cost $50,000-200,000 USD per fluid family).
For most Indian aftermarket, OEM-equivalent positioning ('suitable for Dexron VI applications') is sold under blender's own brand without formal GM license — legally acceptable but excludes blender from factory-fill OEM contracts. Full GM Dexron VI license unlocks OEM dealership channel.
Share your target spec (Dexron VI / CVT / DCT / ATF+4), volume and brand positioning. We respond within one business day with the BOM, FM tuning plan and ex-works cost.