Author Topic: Synthetic oil worthwhile? (Read 1613 times)

Questor · « **on:** June 08, 2009, 04:31:03 AM »

I use Amsoil Saber synthetic oil in my 2 stroke outboard engine because it will sit all week, perhaps two, during the boating season without being started. I like the property of synthetic oil that improves its lubricity on startup in situations like that. Especially in a high performance engine like a 2-stroke outboard. Another thing I like about the Amsoil is that you mix it 100:1 instead of 50:1, which means it's putting less oil into the water.

For other small engines I figure that it's not worth using synthetic because they rest of the apparatus will wear out before the engine does. For example, a lawn mower or snow blower. The engines themselves just don't get a lot of hours on them.

For cars, I think it makes some sense to use synthetic if it's going to be a high mileage vehicle. I use synthetic in my car because I do rack up the miles. For my wife's car, we use conventional oil because the car will be replaced before it gets 200,000 miles on it.

What do you think of synthetic oil?

CannonKrazy · « **Reply #1 on:** June 08, 2009, 11:04:23 AM »

The only thing I run synthetic oil in is my four wheeler. Like you said I don't crank mine sometimes for a few days and the oil adds a little extra protection. As far as my other vehicles I run regular Castrol brand 5-30 and 10-30.

Questor · « **Reply #2 on:** June 08, 2009, 11:14:49 AM »

I'm a Castrol fan too. When I was working on engines in the late 70s I could always tell who used Penzoil for extended periods. They were the gunkiest engines I've ever seen. I assume they've improved their oils since then.

A funny aside:
I did some work on a neighbor lady's car because she was old and couldn't put much money into her car. The oil had not been replaced, just added to. The oil filter weighted several pounds because it was choked with gunk. That old Plymouth Satellite was still running fine even though it had been flowing oil through the bypass instead of the filter probably for years. I think the engine was the 318 v8. I had a landlady that did the same thing with an old Ford Mustang. Just kept adding oil.

Questor · « **Reply #3 on:** June 08, 2009, 12:24:58 PM »

TM7:

I just have to take Amsoil's word for it. I've been using it for about four years and everything seems to be working fine. Their spec for the oil is that it replaces 50:1 oils. It's formulated specifically for outboards, meaning that there's a different oil to use if you're using snowmobiles or what have you. The stuff has been on the market for several years and I couldn't find anything negative on it. Some of the telltale signs I look for are the amount of smoke, which seems reasonable in the sense that there is enough that I'd expect parts to be coated. I haven't opened the engine, but things seem to be working fine.

One thing I can say about some of the modern oils, including gun oils is that they lubricate better than traditional petroleum oils. I've got a gun oil called FP7 that I started using in my 1911 as if it were traditional red lube used by target shooters. Using just a little bit instead of the traditional amounts gives the gun adequate lubrication without nearly as much mess. It's a nice feature. The stuff really sticks too. We had an old box fan that squeaked a lot while running and I figured I'd have to replace it. I'd add a bit of oil to the shaft once in a while and that would quiet it down for a while. Then I lubed it with FP7 and it's been running like a champ ever since. Pretty cool stuff in my book.

greg916 · « **Reply #4 on:** June 09, 2009, 02:33:05 PM »

I have been using synthetics in the transmissions, rears, and bearings on my road tractors for years. Well worth the extra initial investment. The next ones will have synthetics in the crankcase.

The only problem I have had with synthetics is when I changed to synthetics in a higher mileage car. It immediately started leaking oil. I changed back to regularoil and the leaks stopped?

?

Brett · « **Reply #5 on:** June 09, 2009, 03:10:35 PM »

My brother bought a new International Scout with a 345c.i. V-8 back in 1973 that he ran Mobil 1 synthetic in from the 1st oil change. After a couple of decades of driving it he decided to make some modifications to the engine (more radical cam & intake manifold, etc.) and tore the engine down. He found no sludge at all in the bottom of the oil pan and all bearing surfaces were still within original specs. This has sold me on synthetic oils. I run either Castrol Syntec or Mobil 1 one in both my vehicles.

Sourdough · « **Reply #6 on:** June 09, 2009, 05:57:59 PM »

My son uses Mobil One in his Mitsubishi Eclipse, and I use it in my Suzuki Samurai's fresh rebuilt engine. First oil put in the Sammy at rebuild. My neighbor who is a mechanic swears by it.

The only negative I know of was when I had a 97 F-150 with 20,000 miles. I started using Mobil One in it. That engine started going through two quarts of oil every tank of gas. No leaks I could find, and could not see it burning oil, but the oil sure went somewhere. Went back to using 5W30 Penzoil, it quite using oil.

My wife's Mazda RX-8 manual says not to use synthetic oil. The rotary engine needs a thicker oil to help seal the roters, and combustion chambers.

Glanceblamm · « **Reply #7 on:** June 10, 2009, 01:10:38 AM »

I run a synthetic "Golden Spectro 4" in the motorcycle because it is not as subject to "heat break down" as your regular asphalt or parafin based oils. I do not run synthetic in my vehicals because I know of too many cases where it will leak out of areas that just had light seepage with conventional oils.

Oldtimer · « **Reply #8 on:** June 10, 2009, 01:35:50 AM »

I've got to change the oil in my 2008 Toyota Tacoma this morning. I have been running Castrol 5W-20 and after reading this, I am thinking about switching to a synthetic, since I hope to get at least 250,000 miles on this truck. I have been running Mobil 1 in my wife's Passat TDI, as sludge is a major problem with the TDI engine and some of it is related to the turbocharger cooking oil after being run at high speeds and cut off with no cooldown. I was having some problem with oil leakage in the Passat, but I cleaned the oil filter seat and that seems to have taken care of the problem.

Tommyt · « **Reply #9 on:** June 10, 2009, 03:22:24 AM »

When I looked into Syn's and realized how you cannot over heat them it just made sense to use them
I was told that for my Bike that I needed (should)run Dino oil for break-in then I know others that run it straight from the showroom
I also think so much of it I run it a lot longer in between changes I due however change the Filters @ 3000

slim rem 7 · « **Reply #10 on:** June 10, 2009, 03:50:59 AM »

mobile 1 is an excellent oil....this will sound silly.. but if you want your car to totally wear out around an engine thats still good... don t let the oil get visibly dirty... i had a bankruptsy shortly after buying my 90 festiva that i used for weekly work trips etc.... i knew it had to last ...
i did this an the speedometer broke at 332 thousand,, several years ago..... the car was finally sold last year.... it leaked but didn t burn oil....slim

gstewart44 · « **Reply #11 on:** June 10, 2009, 04:37:41 AM »

I have a 2004 Nissan Titan with 136K miles on it. After the first oil change I started using MObil 1 every 5K miles. The truck runs perfectly, does not use up any oil and gets great (18 mpg hwy) gas mileage for a big truck.

Torg · « **Reply #12 on:** June 10, 2009, 08:55:32 AM »

Mobil 1
Good'nuf for Smokey, good'nuf for us....

boondocker · « **Reply #13 on:** June 10, 2009, 01:25:49 PM »

As a mechanic I swear by synthetics in every component. You will make your components last longer and you will get better fuel mileage. The deal with oil leaks is that if you let the miles build up on dinosaur oil it lays a black film on the iron which is a mixture of dirt and component wear. That is what lets the synthetic weep by the seals as they have that film also. I do not think it is worth while changing gaskets and seals on older engines tho. When I was a fleet maintenance manager for WM and I had the guys switch all the running gear oils over they changed all the seals, worth while fuel saving and less component wear. Gas engines ran syn and the diesels we ran Rotella T dino oil. I would stay under 30 k on engine oil switch over. My 05 Grand Cherokee I switched at 32 k and had a head gasket weep for 4k but it sealed. A fellow mech I work with bought a 93 Explorer stick off a road salesman that ran nothing but syn 21 mpg. Went to 18 on dino oil he switched back and got 21. 300k+ and runs like new. 4k filter change and 8k oil and filter change. 50k ago he switched to Walmart brand and still no difference. Thats my story and I am sticken to it.

AtlLaw · « **Reply #14 on:** June 10, 2009, 02:02:31 PM »

I to broke my last bike in with dino oil then switched to Amsoil. Been real happy so far, new filter every 3K oil change every 6.

victorcharlie · « **Reply #15 on:** June 10, 2009, 03:56:52 PM »

I've always used regular plain dino oil. I've got 235 thousand on my 95 nissan now, and the one before it (86) had 249,000 on it before I crashed it.

I guess this is somewhat like premium bullets. Some require them and others don't. I don't see that one works any better than the other for most applications.

Retsof · « **Reply #16 on:** August 10, 2009, 12:36:36 PM »

I can only relate my personal experience in using synthetic oil. So, take it for what's it worth.

I had a 1990 Chevy Ext. Cab P/U truck (gas) with the short block 350 engine and a 5-speed manual transmission. I sold it 11 years later. When I sold it, I had 377,000+ miles on it but still had the orginal engine and transmission. Up until 100K miles or so, I has used Pennzoil 30 wt. After that, I started using Castrol Syntec 10W-30 for the engine and Royal Purple Synthetic in the transmission. Did the synthetics really account for the high mileage? I don't have a clue but I did not have any leaks, until just before I sold it. One time, when I was driving to SE LA from Amarillo, TX, (about a 12 hour drive) in August, I noticed that when I was in bumper-to-bumper traffic in Dallas, the temperature gauge would get uncomfortably close to the red line. However, when I started travelling at regular I-10 speeds, the temperature would again drop to just about normal levels. When I finally got home, I checked the radiator level and was shocked to find that, if there was water in the radiator, I couldn't see it. Come to find out that a ceramic fitting at the top of the engine manifold was cracked and the coolant was vaporizing away, while I was travelling that day. Now, I doubt that the radiator was completely empty but I do know that Castrol Syntec 10W-30 was in my engine at that time. Would a regular oil have endured this stress? Once again, I really don't know but I'm glad I didn't get to find out.

My wife drove a Camry for 240K+ miles before she got a new vehicle. I had used the Castrol Syntec 5W-30 after the Camry had about 1K miles on it. No engine trouble at all. I do my own oil changes. One time I was out of town on an extended project and did not have a chance to change the Camry oil (and I forgot to mention to her to have it changed). When I got back, I finally changed it and realized that it had been just over 18K miles since I last changed it. I certainly do not recommend this practice but it had no ill effects (at least this 1 time).

Finally, I have a 2001 Tundra with 115K+ miles on it. After the first 1K miles, I began putting Mobil 1 10W-30 in it (sometimes 5W-30,when Wally World is out of the 10W-30). So far, so good.

One thing I do like about using synthetics is that after each 5K miles, all I do is change the oil filter and top off the engine with synthetic oil. Then, after the next 5K miles (or 10K miles total), I'll do a complete oil and filter change. This helps lessen the cost of synthetic vs regular motor oil. Another thing I like about synthetic oil is that I do not have to change the oil precisely at the 5K mile mark. With regular oil, I'd not go beyond 3K miles. This may not be necessary but old habits die hard.

Just my $.02 worth. YMMV.

Lloyd Smale · « **Reply #17 on:** August 11, 2009, 12:20:19 AM »

Im a firm beliver in them and for the last 20 years there all ive used in anything i own that uses oil.

Drilling Man · « **Reply #18 on:** August 11, 2009, 04:24:16 AM »

Over the years, i've also run a lot of both oil's... I think there's times when synthetics are worth it, and times when they aren't. For my car's and trucks i don't run syn., i DO change the oil regularly in them... I'd rather see clean oil go in them "regularly", than expensive oil that's left in longer. I have no problem getting over 200,000 miles out of an engine with dino oil, and the rest of the car is junk by then, or rusted out...

In my equipment (dozer, tractors and all diesels) i run 15-40 Rotella

In my small gas "air cooled" motors that get worked hard, i run Mobil 1 synthetic...

I also run synthetic in the rear's and manual trannys of the car/trucks

DM

ihookem · « **Reply #19 on:** August 18, 2009, 03:45:28 PM »

I am going Amsoil in everything, even my chainsaws. A mason down the road has used Amsoil Saber in his chop saw and never blew an engine in the 12 years he has been using it. He uses the saws every day too. I am sure 100:1 is enough if Amsoil says it's enough. You can bet they test the living heck out of the oil.

Tonk · « **Reply #20 on:** November 26, 2009, 02:05:40 PM »

We use Castrol "full synthetic" for all our vehicles, except the diesel tractor. I picked up 2 miles per gallon using the full synthetic oil. I change oil every 5k nowdays and things been just great in our vehicles. I am a firm believer in Full Synthetic oils like Mobile 1, Castrol and Valvoline.