PRO-SYN 85W250
Synthetic multigrade lubricant for gearboxes


PROLAB's PRO-SYN 85W250 is a multigrade synthetic lubricant for worm gearboxes with exceptional properties which allow it to outclass conventional lubricants both synthetic and mineral oil based.

Characteristics and Benefits

The PRO-SYN 85W250 multigrade synthetic lubricant is diesters formulated. It has exceptional characteristics that are particularly efficient against extreme pressures and high operating temperatures and its anti-wear properties have shown exceptional results. The PRO-SYN 85W250 offers considerable advantages over conventional lubricants: it has the power to clean varnish and sludge while offering excellent polarization to metal surfaces and can be used in harsh weather conditions, from extremely warm to extremely cold.

Types of Application

Use PRO-SYN 85W250 in industrial worm gearboxes.


PROLAB's PRO-SYN 85W250 is fully compatible with soft metals (such as bronze alloys) and is compatible with most of industrial paints and seals used with conventional lubricants.

Directions for Use

Follow the manufacturer's instructions for the lubrication of the specific piece of equipment.


For better results, it is highly recommended to use PROLAB's DE-25 Decontaminant prior to using a new lubricant.


Never mix two different synthetic lubricants without first making sure they are compatible.

Available Sizes

4 L, 20 L, 55 L, 205 L

Product Code

# 490



characteristics astm  test typical values
Flash point D92 250oC
Fire point D92 295oC
Pour point D97 -35oC
Viscosity at 40oC D445 433 cSt
Viscosity at 100oC D445 47 cSt
Viscosity index D2270 167
Total acide number D664 0,6 mg KOH/g
Total base number D2896 0,4 mg KOH/g
Rust preventative(A) distilled water(B) sea water D665  PassPass
Foaming characteristics- Sequence #1- Sequence #2- Sequence #3 D892  25/0 ml610/0 ml320/0 ml
Demulsibility- water in oil- total free water- emulsion D2711B  4 %60 ml0 ml
Corrosion - Copper strip D130 1a
4-ball wear D4172 0,4 mm
4-ball wear EP- load wear index- weld load D2783  46250 kg