No, this is my thread and I asked Hydro for his opinion. See my opening post.
Sheesh, why can't everybody mind their own business!

Hydro, so in a 502 MPI 415 HP appilcation, ~ 300 hrs, that is stock except for Gaffrig air cleaners and soon to be Stainless Marine exhaust, you feel the 15-40 is the way to go, or should I look @ the 20-50. We idle ALOT with all the Manatee Zones and I change my oil ~25-30 hours, so once again, I'm asking you for your opinion, just so everybody is clear!
Thanks,
Dean

Oops, sorry to have commented. But it was my understanding that when you start a thread it was open for ALL to comment. A PM to Hydro would prevented our interference and your annoyance. --- Jer

Long-duration idling causes more oil and oil filter deterioration and increases the need for more oil and filter changes no matter which oil you pick.

The choice between 15W-40 Amsoil Marine or Amsoil 20W-50 Severe Service Racing is a tough call as both are real good... while the Racing product would be best if you run hard for long periods.

If the price you can get between the two products is not much different.. go for the 20W-50. If you can get the 15W-40 "cheap" then I see no reason to not use it. Both are really good products.

I thought you were supposed to go WOT in Manatee zones to get up on top of the water to avoid them...

JP,
I wasn't referring to you in my "mind your own bus." comment. Your 1st post was the kind of info. I was looking for. As for the 2nd post....
BTW, I went to school in Geneseo! Man, what a party town!
Thanks,
Dean

I thought you were supposed to go WOT in Manatee zones to get up on top of the water to avoid them... [/QUOTE]


HC,
Thanks for your knowledge on oil, and I'm going to see what the $$ delta is between the 15/40 vs 20-50 and go with the best deal!
Love to try out your Manatee Zone theroy, BUT I'm the loudest boat on Sykes creek!!
Thanks again,
Dean

HC,
Thanks for your knowledge on oil, and I'm going to see what the $$ delta is between the 15/40 vs 20-50 and go with the best deal!
Love to try out your Manatee Zone theory, BUT I'm the loudest boat on Sykes creek!!
Thanks again,
Dean[/QUOTE]

You won't go wrong with either choice the Amsoil 15W-40 is really a great product as it has great detergency and dispersion properties ...so much so you can use it in a diesel engine...and a great base stock....very good anti-wear additives too.

I have used several of Amsoil's products and always had great results. The 15W-40 also has a great anti-corrosion additive system and it offers excellent film strength. If you can get a good price on it don't hesitate.

Amsoil synthetic oils are durable and dependable.

What do you think of the Amsoil 60W racing oil for a big blower motor?

Ive been using the 15/40 Amsoil for a few years now just for the fact of soot and gas thinning in a procharged 502 with close to 300 hours and it has held up great. I dont lose any between 20 hour changes.

Jim

I just purchased a boat with 20w50 Race synthetic in the engines (500hp) and 75w90 Marine synthetic gear lube in the drives. I just serviced the engines for the season. The oil pressure idling with the Amsoil was ~40-45 on the engines when up to temp. Due to availability, I have put 50w Royal Purple synthetic in the engines this round to shake down for comparison. I did notice on the hose at idle port engine oil pressure was 50-52 and starboard was ~58psi (approx 8-10 psi higher on each engine). This may be for the fact that they were on the hose and not run under a load. The engines were up to temperature, however. I did chane filters, but the old ones didn't look bad; so, I cannot imagine there was a large deltaP across the old filter.

I will continue using the Amsoil gear lube in the drives. I am told it's bullet-proof...


Comments and questions on what I 've done?

Zack

My wife is a dealer for Amsoil , I use the gear oil in my fountain and before I starting using it I had a friend use it for three years with no problems in the motor and the drive. I use the grease, chain case oil, four stroke in my mowers and tillers and four wheeler and the two stroke in my fishing boat. no problems if any one wants some let me know.