Synthetic Oil in Vortec 5.7

[dslkd]

Does anyone run fully synthetic or synthetic blend in their Vortec? If so what brand and weight. also anyone tried synthetic trany fluid?

Thanks,
Ben

[2kims]

syn in vortec

i run synthetic in my 3500 chev 7.4L gas truck. 140000 miles and my VW TDI. i plan to put it in the 24v when its time for an oil change. I use Amsoil Series 3000 5-40W. I plan on using the same in the tige. we put about 125hrs a season on our boat.

[dslkd]

If I run synthetic I am Going to use Amsoil for sure.

[Tige M.D.]

check with the manufacture first. alot of them only warranty their product with certain oils. if there is a failure and the engineers find that it had unauthorized oil in it you can loose your warranty.

[dslkd]

Do you have any idea what they suggest for the Votecs the manual doesn't say anythig about what brands to use.

[Tige M.D.]

just called marine power and they are going to get back with me shortly.

[dslkd]

Thanks, What brand and weight oil do you normaly service with in both tranny and engine?

[Tige M.D.]

marine power has no problem with you using synthetic oil in the engine.
we use valvoline 40wt in the engine and dexron III in the transmission.

[dslkd]

Thats good to know Thanks for all yor help!!! I guess il contact amsoil and see what they suggest, ans try it this oil change. They didn't happen to say if they had noticed any diffrence or if it was worth the exta money ?

Ben

[GIZMO]

I build engines for sand rails and use mobil 1 or Red Line, They seem to hold up the best.

P.S. Dont change to synthetic unil the motors broke in.

[dslkd]

Its got about 45hrs so it should be broke in i think. What is the fluid capcity of the trany fluid on the 22V I cant find my book and the dealer here knows less than I do.

[Tige M.D.]

approx. 1 1/2 qts.

[Ruune]

isnt marine oil formulated differently for a higher humidity, given that there is humid air going through the engine?

Isnt the advantage of synthetic that it breaks down less under high heat? That said, and given the fact that we've got a constant supply of cool water coming into the cooling system, doesnt that negate the advantage?

Just a thought.

[raythompson]

Originally posted by Ruune
isnt marine oil formulated differently for a higher humidity, given that there is humid air going through the engine?

Isnt the advantage of synthetic that it breaks down less under high heat? That said, and given the fact that we've got a constant supply of cool water coming into the cooling system, doesnt that negate the advantage?

Just a thought.

Yes, those are all partly true.

The humidity is not an issue as in the south (as you know) the humidity can get quite high and cars survive with no problems. When the air is moving the humidity is not much greater on the water than what is normally in the air. The heat of the engine and oil will evaporate any water that gets into the oil. Besides most engine crankcases are sealed and moisture should not get into the oil.

The cooling supply may be plentiful and at a constant temperature, but the engine is stull subject to a lot of heat generation, especially under high load. And marine engines are almost always under high load. Hot spots still develop in the engine.

Synthetic oil is also supposed to handle higher load pressures on the bearing surfaces without the lubricating film being squeezed out. This is supposed to prevent any metal to metal contact on the bearing surfaces.

Now my opinion is that synthetic is a waste of money. Change your regular oil often along with the filter and an engine will last a very long time. My old boat was 20 years old with thousands of hours and the engine was still working fine. The oil was changed twice during the summer working season, once at the beginning, and once about in the middle of the season.

The boat started it's life on Canyon Lake Northwest of San Antonio and also spent some time on the Guadalupe River (put in where I-10 crossed the river). A lot of time was spent on Canyon Lake. Now I live in Tennessee where the lakes are bigger, and more importantly, much much smoother than Canyon Lake. And we don't have to dodge sail boats.

[Ruune]

thanks for the clarifications... and yeah, Canyon can get kinda choppy! Medina is really nice... theres always calm water SOMEWHERE! We dont have many sailboats to dodge, but Jethro and his brother/cousins Jim-bob and Joe-bob in their "fitty horse skeeters" and NASCAR hats, camo clothes shirts and florescent PFDs (never quite got that) are another story.