GMN >> Freewheel Clutches > Service > Lubrication > Spragtype clutches

Indications of lubrication for spragtype clutches

Proper lubrication with only qualified lubricants is the prerequisite for achievement of highest efficiency and long life of our high quality clutches. Only with use of oil or grease lubricants specified in the tables below, GMN warrants trouble-free operation of its freewheel clutches. Whenever possible, use only oil or oil mist lubrication rather than grease lubrication.

Please contact our technical staff if operating temperatures are in the upper or lower temperature tolerance range, if the clutch has to be mounted in vertical position or if there should be any other special conditions.

It is not allowed to use any lubricants with additives (for example MoS₂ or graphite),
which are decreasing the friction coefficient!

Oil

For oil mist lubrication please use hydraulic oil HM 10 or HM 32.

Oil type	Operating temperature range
	-15º C to +30º C 5° F to 86° F	15º C to 90º C 59° F to 194° F	60º C to 120º C 140° F to 248° F
Hydraulic Oil	Hydraulic Oil HM 10	Hydraulic Oil HM 32	Hydraulic Oil HM 100
Motor Oil		HD-Motor Oil SAE 10 WATF-DEXRON III	HD-Motor Oil SAE 30

Oil lubricants described above - except hydraulic oil - are from the automotive sector. These lubricants can easily be obtained at automotive supply outlets and are excellent for the lubrication of our freewheel clutches. Lubricant qualification: HD-motor oil SAE 10 W or SAE 30 is equal to "API-Service SE or CC" and MIL-L-46152B".

Important: Oils shown in the table are only to be mixed with oils of the same grade. That means ATF oil with ATF oil, HD-motor oil with HD-motor oil etc. If there is any change of oil from one grade to the other, it is necessary to clean the freewheel clutch and mating parts with cleaning or test benzine. Never use trichloroethylene or perchloroethylene.

The oil level should be in relation to the size of the freewheel clutch. In normal installation position, not operating, one third of the clutch should be submerged in oil.

For oil mist lubrication systems we recommend ample clean oil, free of moisture, be sprayed directly onto clutches. Open or unsealed housings should be inspected frequently for proper lubrication level.

Our double sealed freewheel clutches (series FND and FPD) are filled with oil for operating temperature range 15° C to 90° C if not specially ordered.

Grease

Greases from different manufacturers are not always compatible. Consult GMN for proper lubrication recommendations. Please note: There is no universal grease for all service and operating conditions. The table below lists suitable grease types and characteristics for GMN freewheel clutches:

Producer	Grease type	Saponification	Oilbase	Operating temperature for GMN freewheel clutches	Characteristics
Klüber Lubrication	ISOFLEX LDS18 Special A	Lithium	Ester/ Mineral	-30°C... 130°C -22°F... 266°F	Low temperature and long-term grease with high resistance to aging and corrosion.
Shell	Alvania RS	Lithium	Mineral	-10°C... 120°C 14°F... 248°F	Long term grease with high resistance to aging and corrosion.
Klüber Lubrication	Bio BM 72-501	Polyurea	Ester	-20°C... 120°C -4°F... 248°F	Biological grease especially for overrunning and backstopping.
Klüber Lubrication	Synth HB 72-102	Polyurea	Ester	-40°C... 180°C -40°F... 356°F	Synthetic grease especially for overrunning and backstopping.

The first two grease types are to be used in standard applications.

The amount of grease should cover approximately 60% of the free volume in the clutch. Please take care for homogeneous dispersion of the grease all over the clutch.

GMN uses ball and roller bearing grease which is continually monitored for maximum quality and maximum clutch life. Sealed ball bearing clutches "RS" and "2RS" are shipped grease lubricated with grease type Isoflex LDS 18 Special A, if not specially ordered. GMN can not endorse or guarantee the quality of lubricants, purchased by their customers to be used with GMN clutches. Last update of the qualifications: June 2007.