4.3 Lx Mercruiser

I have an older 1994 Larson boat with a 4.3 LX Mercruiser Alpha one Gen II sterndrive. The original operators manual calls for 30W motor oil. It is becoming increasingly more difficult to find this single viscosity grade of oil. Is there an alternate multiple viscosity oil that will work for this setup.

Also the last time I bought Mercruiser High performance lower gear drive oil for the sterndrive, it was 15.00 per quart. At Wal Mart they also sell a lower gear drive oil for 10.00 per quart which is also made by Mercruiser. Do I really need to spend the extra for the high performace. I also bought some gear drive oil from West Marine that they said would work in the sterndrive, but then after going back and asking another salesperson, they said no.
Anyone else run in to this problem.

Thanks for your comments.......................bill

Re: 4.3 Lx Mercruiser

Nobody likes oil questions

I think you can use 20-50 for motor oil, maybe even 15-40.

Outdrive has several options, depends on what you need/want. Most synthetic gear oils will "work", but ideally one that is rated for marine use is best due to supposedly better lubrication when contaminated. Amsoil makes a gear lube that will work as does Pennzoil as well as others, but I would use synthetic at least.

Just my opinion, others will vary.

Re: 4.3 Lx Mercruiser

My Volvo Penta manual for a 2003 4.3 GL-A allows 20-50 or 15-40 at temps above 32 F. I use marine lower gear lube 75W-90 full synthetic. The last time I changed it, the only brand available was Mobil and it was around $17 a quart. Ouch!