gl5 tranny oil

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gl5 tranny oil


Post by 49er » Sun Aug 23, 2009 11:46 pm

Hey, I read on another site that 90 wt that is rated gl5 has an acid that attacks phosphorus bronze bushings. they said to use only gl4, which is getting hard to find. what do you think of that? are the bushings in old trannys phosphorbronze? mine are over 30 yrs old.

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Re: gl5 tranny oil


Post by RUBONE » Mon Aug 24, 2009 3:11 am

H-D always recommended using motor oil in the transmission in the older bikes. Way back in the sixties our old time dealer claimed that it was because of bushing issues with gear oils. I know in other older bikes gear oil can also attack seals that were not made for it. I personally only use straight 50 in my gearboxes on my Knuckle, Pan, 45, and UL

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