Mobil Delvac 1™ Transmission Fluid 40

Supreme performance transmission lubricant

Introducing Mobil Delvac 1 Transmission Fluid 40, a full synthetic, manual transmission lubricant engineered to meet some of the most demanding extended drain and original equipment manufacturer (OEM) warranty requirements.

Mobil Delvac 1 Transmission Fluid 40 is recommended for year-round lubrication of manual transmissions in light- to severe-duty on- and off-highway equipment operating in a wide range of environments.

Designed to provide maximum protection and extended operating life to heavy-duty transmissions, Mobil Delvac 1 Transmission Fluid 40 provides outstanding high-temperature performance, oxidation stability, wear protection and corrosion control.

The outstanding performance of Mobil Delvac 1 Transmission Fluid 40 is confirmed by approval for heavy-duty transmissions covered by Eaton Roadranger and extended warranties of 750,000 miles, with oil drains of 500,000 miles. It is also approved against the Mack TO-A Plus 500,000 mile extended service classification for Mack T300 series manual transmissions.

Mobil Delvac 1 Transmission Fluid 40 meets or exceeds the requirements of the API service MT-1 classification and is recommended by ExxonMobil for use in transmissions and gear cases where API Service GL-1 through GL-4 (non-EP) gear protection is required.

Mobil Delvac 1 Transmission Fluid 40 is recommended for use in:

  • Heavy-duty manual transmissions where extended service intervals and warranties are required
  • Commercial line haul, vocational, off-road, pick-up and delivery, and bus applications
  • As a companion with Mobil Delvac 1™ Gear Oils in rear axles for maximum component life, service efficiency and fuel economy improvement

Features and benefits

  • Excellent load-carrying and anti-wear performance helps to extend transmission life and reduce operating costs
  • Maximum protection from corrosion of copper and its alloys can extend the life of synchronizers
  • Exceptional shear stability minimizes wear during severe operation
  • Outstanding protection against deposit formation can lead to longer seal life, extended drain and service intervals
  • Optimized thermal and oxidation protection helps extend component life and improves efficiency

Specifications, approvals and technical details

Specifications and approvals  

Mobil Delvac 1 Transmission Fluid 40 meets or exceeds the requirements of the following industry and builder specifications:

  • API MT-1

Mobil Delvac 1 Transmission Fluid 40 has the following builder approvals:

  • Eaton PS-386
  • Mack TO-A PLUS
  • Navistar MPAPS B-6816 Type 2

Technical details  

SAE Grade


Viscosity, ASTM D 445

cSt @ 40ºC


cSt @ 100°C


Viscosity Index, ASTM D 2270


Pour Point, ºC, ASTM D 97


Flash Point, ºC, ASTM D 92


Density @15º C g/ml, ASTM D 4052


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