Switching from Synthenic to Dyno Oil?

Jarlaxle wrote:
Oil is oil. Use whatever oil that meets the requirements that you can get the cheapest.

This is what I do but have some observations. I switched to WM syn 10-30 for MH and tow car about 6-7 years ago. First drain on syn in MH noticed a lot of small chunks of carbon in oil, other than that no improvement in MPG or lower operating temps. When I put it in my 2002 Toyota Corolla it leaked around the pan for several oil changes and several re torquing of the pan bolts. Same kind of carbon deposits in oil change with the syn. I had a slight oil leak in my generator when I used syn I made it much worst. I will go back to Dino oil for the gen set, but will use what ever is on sale for the tow car and MH.

It is good to see that some things don't change. These are the same debates we have been having for decades. Enjoy the reading.

For the record I use Synthetic blend.

Oil is oil. Use whatever oil that meets the requirements that you can get the cheapest.

Hi All.

Even back from my Racing Days, many, many moons ago, we never used any Synthetic Oils. We have always used just Rotella 5W-40.

Today, all of are engines are using Rotella 5W-40 oil, with no problems what so ever. Its good enough for our Motorhomes 460 EFI. Even our Toad, our Honda CR-V. We even went one step further, and its in our Motorhomes Generator. It acturally make our Motorhomes Generator a tad bit quitter, enough so that you can for sure tell the difference.

We towed a 5er with a 1997 F-250 H.D. PSD with our 5th Wheel Trailer. Over 100,000 miles on it with not a problem at all, except for the basic stuff, oil changes, Tires, Battries.

We have never Broken Down, or have ever had a Blow-Out of a Flat Tire. Or any kind of any trouble at all in the 45+ years as RV'ers, that I couldn't fix on the go.

It realy does help to do your "Proventive Maintaince Programs" as they are needed. Take good care of your RV, and your RV will take good care of you.

Working on any of our RV's we have ever had has been a pleasure to work on, since I love to do it, it not work to me.

We have just been lucky to have a place to keep our Motorhome on our Property, and the skills t be able to work on them.

Good Luck. Happy Travels. Dan & Jill & our 2 YORKIE KIDS.

Hi All.

Even back from my Racing Days, many, many moons ago, we never used any Synthetic Oils. We have always used just Rotella 5W-40.

Today, all of are engines are using Rotella 5W-40 oil, with no problems what so ever. Its good enough for our Motorhomes 460 EFI. Even our Toad, our Honda CR-V. We even went one step further, and its in our Motorhomes Generator. It acturally make our Motorhomes Generator a tad bit quitter, enough so that you can for sure tell the difference.

We towed a 5er with a 1997 F-250 H.D. PSD with our 5th Wheel Trailer. Over 100,000 miles on it with not a problem at all, except for the basic stuff, oil changes, Tires, Battries.

We have never Broken Down, or have ever had a Blow-Out of a Flat Tire. Or any kind of any trouble at all in the 45+ years as RV'ers, that I couldn't fix on the go.

It realy does help to do your "Proventive Maintaince Programs" as they are needed. Take good care of your RV, and your RV will take good care of you.

Working on any of our RV's we have ever had has been a pleasure to work on, since I love to do it, it not work to me.

We have just been lucky to have a place to keep our Motorhome on our Property, and the skills t be able to work on them.

Good Luck. Happy Travels. Dan & Jill & our 2 YORKIE KIDS.

RayChez wrote:
Just the filter alone is a job and a half wrestling with it trying to get leverage to unscrew it off on diesel engines.

You should have seen the 2 guys at walmart trying to get the filter off my cummins. LOL It was worth the $20 just to watch them wiggle this way and then wiggle that way and swearing in spanish the whole time.

If you buy your own oil and filter walmart will swap it out for a paltry $20. A deal I couldnt resist, and as I mentioned it came with an entertainment package.

wca01 wrote:
I have been testing engine oils in autos, trucks, and motor homes since 2000.

Engine oil doesn't wear out, it just gets dirty and that depletes the oil additive package. When the additive package is depleted, the oil gets dirtier, and the process continues to multiply. The dirt and depletion of the additive package is the result of products of combustion escaping the cylinders and contaminating the oil.

You'll want to research the effects of combustion gasses have on the oil. It does wear out because the raw gas dilutes it. It's why the oil feels like syrup when new and water when drained. Diluted oil allows much more metal to metal contact as it simply cant resist the compression exerted on it.

Synthetic oil's primary benefit is the high resistance to dilution from blowby gasses.

427435 wrote:

Gale Hawkins wrote:


I think dino oil changed at 3000 for normal wear is as good as changing at 7500+ when using synthetic in gas engines. Thin synthetic on start up is the best part about synthetic from my understanding.

Besides the improved cold-start lube and reduced viscosity reduction that synthetic oils give, the extended oil change is a big plus. No changing in the middle of a long trip and less rolling around on the ground changing oil. My old bones don't find the oil changing process as easy as when I was 50.

Changing eight quarts of oil on your sun cruiser is a piece of cake in comparison to the twenty quarts on a diesel. Just the filter alone is a job and a half wrestling with it trying to get leverage to unscrew it off on diesel engines.

Gasoline engines takes about twenty minutes to change. Diesels take about an hour or more to completely finish the job.

Gale Hawkins wrote:


I think dino oil changed at 3000 for normal wear is as good as changing at 7500+ when using synthetic in gas engines. Thin synthetic on start up is the best part about synthetic from my understanding.

Besides the improved cold-start lube and reduced viscosity reduction that synthetic oils give, the extended oil change is a big plus. No changing in the middle of a long trip and less rolling around on the ground changing oil. My old bones don't find the oil changing process as easy as when I was 50.

Good point Travelon. I moved to synthetic in our 454 when we got it with 92,000 miles on it because the price difference gap between dino and the WM full synthetic had closed so much by 2007. For an engine that sets most of the time my research (reading) indicates synthetic should give better protection on start up if using something like 5W-40 Rotella like we current use. It is actually approaching 0W-xx that gives the edge I read.

Almost loss the 5.3L GM engine in the SUV due to a sticking oil pump relief by-pass valve when using dino around the 130K mile mark. With Sea Foam in the new dino oil change for 160 miles it stopped hanging when hot then I replaced with Mobil 1 High Mileage 10W-40 for one change. After about 100 miles with it (no Sea Foam) the needle quite flickering at higher RPM's like when driving 70-75 MPH with OD locked out. We now have Mobil 1 5W-30 which is the weight per GM manual.

Not saying the dino was the cause. The prior change of dino was done when GM dash said change which was 7500 miles because I was not driving the SUV at the time. We normally changed it about 5000 miles in the past. We bought it with 102K miles and know they had it changed at the dealership but do not know what they use. It is my take synthetic motor oil is more high detergent but it may not be.

What triggered the sticking pressure relief valve was I took it to get the oil changed because I was stressed it went to 7500 miles and on the way home I did some WOT (wide open throttle take offs letting it shift per the GM programmed shift points. The wife will not do that. I think a WOT take off is required from time to time to keep full range of motion of all moving parts. If one does not do it for years then someone does valves of all kind can start to stick because they move into areas that have a build up on the metal parts.

The 454 in the MH gets WOT starts especially on interstate ramps, etc and when doing exercise runs but only when temp is up to about 200 on the dash. The upshifts come at 4000 RPM like clock work so it is good for the transmission check too.

If our 454 does not run smooth to the 4000 number or the shifting is delayed I know I have a bad plug wire, dirty fuel filter, etc hence why it is important to do WOT take off before doing a cross country that will take one across the Rockies. :)

Key I think for engine oil and ATF is that you never run it when it gets dirty. Synthetics are great but if it gets dirty you will still get a lot of wear on parts. I have found just changing the oil filter and topping off can clear up dirty looking motor oil. On the transmissions we do the buck flushes because that removes about 97% of the old ATF because the old does not get to return to the transmission but goes in a 5 gallon bucket (hence it is called a bucket flush). We have an add on cooler so pulling the line and dumping the return line into the bucket is a stand up job that takes a minute.

I think dino oil changed at 3000 for normal wear is as good as changing at 7500+ when using synthetic in gas engines. Thin synthetic on start up is the best part about synthetic from my understanding.