Replacing Lower Unit Gear Fluid & Flush?

[Coastal238]

I have a 1994 Johnson Ocean Runner 225, which I intend to replace the lower unit fluid. After draining it, do you flush it out with something? <br /><br />Also, I was planning on changing to a penziol synthetic blend, but only found it at 75 weight. Can I use this and is there any concerns with synthetic?<br /><br />Any help is appreciated!

 

[dajohnson53]

Re: Replacing Lower Unit Gear Fluid & Flush?

Generally, you don't need to flush. I"ve heard of people filling it with clean oil, letting that drain out then filling it again with fresh.<br /><br />Just buy a lower unit lube rated for marine use and/or the type that's specified in your engine's manual. If it were me, and I couldn't find the oil specified for my engine in synthetic, I'd just buy dino.

 

[ezeke]

Re: Replacing Lower Unit Gear Fluid & Flush?

You need high viscosity oil rated GL-5. I use 100% synthetic from pennzoil.<br /> Pennzoil