Regular oil vs. synthetics vs. Amsoil et al.

jeepinmatt

jeepinmatt

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Are the high end oils worth the cost? I just bought the wife a new-to-us 4Runner and would like to maximize efficiency and life. It's got 80k miles on it now and if it's anything like her last vehicle, we'll keep it till about 250k miles. I've ran synthetic in my car since 70k miles, and just had the oil pan off and everything looked like new at 200k miles. I've always run regular valvoline in my jeeps. Is Amsoil worth the extra compared to regular synthetics?
 
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Nobody has any insight?
 
I only run synthetics and have been that way for close to a decade. I use to run royal purple as it was the same cost a Mobil one. Now I run Mobil one as that is what costco sells. Haven't really noticed a difference other than the cool purple color.
 
i'm not a fan of royal purple, some like it but i think it's just commercialized. i will swear by amsoil and 99% of their products, as i have seen the results in race applications and personally driven vehicles.
as far as conventional vs synthetics, the gains in using synthetics are marginal but there are still gains in using them.
 
My opinion, it's worth it if you extend your oil change to balance the cost of synthetic. But for the average Joe, if you do regular oil & quality filter changes, I'd expect the same life of engine. I had a Toyota Celica for 5 years. Bought it with 180K on it, & sold it with 230K. I'm sure it had been on standard oil, & the only problem was leaky valve seals. I didn't expect to do this, but I sold it, & bought a 05 Ford Escape, 3.0 V6. It's got 242K, & singing a fine tune. I Highly doubt it had any synthetic. Now my basic tow rig, 98 Chevy Z-71, has been on syn., since 50K, when I bought it. Every fluid in it was changed to syn., mainly for added protection, towing. Especially the automatic. Haven't experienced any problems connected to oil, but I change the oil, & filter every year, Same as I've been doing my CJ. But, I only run 4-5K on the truck, & 3K on the CJ, within a year. There, I'm probably wasting money. I doubt there's enough difference, if any, in regular Brands, to matter. Amsoil may be a slight step ahead, & Royal Purple, only if I had a $30,000 or more Race engine. I do believe you can gain slight gas mileage improvement, but will it balance the cost? Also, on used engines, & accessories, synthetic can create leaks. Going to depend on mileage, & condition. Just my experience, opinions, & thought passed from others!
 
The biggest benefit to synthetic is the stability of the oil. Dino oil is compromised of organic irregular molecular structures. The irregular structures cause a weak link where they attach to one another. Synthetic oil is made from completely uniform molecular structures. This creates a stronger bond.
 
Synthetic can lead to leaks since it does not penetrate and lubricate older gasket materials found on older engines.
 
I've been using the synthetic blends for years usually get the oil/filter deals/sales for about $25 w Purolator Gold filter. My mileage is better w the blends instead of conventional and cold weather starts also improved. I change @ 4500/5000.
 
With the deals you can find on synthetics now and the cost of dino oil, I see no reason not to run it. WalMart has Mobil1 on sale all the time and Autozone always has combo deals for 5 quarts of oil and a filter for cheap.
 
mommucked said:
I've been using the synthetic blends for years usually get the oil/filter deals/sales for about $25 w Purolator Gold filter. My mileage is better w the blends instead of conventional and cold weather starts also improved. I change @ 4500/5000.
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Most synthetics, will run for 15,000 miles, which would pay for itself, + being a better lubricant. But I'd be doing a oil analysis, to see When I need to change it. So, you add another cost.
 
My wife's new Highlander requires 0W-20 weight oil. I had never even heard of that weight oil before buying that car. When I went to the parts store to buy it (Advance IIRC), they only had full synthetic in that weight. The car manual states that the oil change interval is 10,000 miles if using synthetic, so that is what I am doing.

I owned a 98 Tahoe with the 350 for a while. I bought it with 66k on the clock, and supposedly some old man had owned it before me. It looked immaculate, and well taken care of. I sold it with 140k maybe. I ran Mobil 1 full synthetic in it, and changed it more frequently than necessary. Around 100k-110k miles, the distributor drive gear wore out, causing it to run funny. Not sure what that says.

I run conventional motor oil in all of my other vehicles, and change the oil on the manufactures specified intervals.
 
The distributor gears on those motors were a pretty common issue. I've seen dozens wear out, regardless of oil type. I see your point though.

I've been running Mobil 1 for a while now. I'd run Amsoil if it was on the shelf at Advance or Walmart, but it's not. They say 25k or 1 year and they say change the filter every 5,000. I worked up the math for my K30 a while ago and it would save me quite a bit on oil changes vs. Rotella, but I don't drive it enough to worry about it. It also leaks some, so I wouldn't want to waste the oil. 4 gallons of oil and 5 filters was way cheaper over 25k than the 5 regular oil changes I would have done.

I have a buddy that had an LQ9 let go after running Royal Purple for a while. The rings were ultimately to blame when they swelled up from 14 lbs of boost from a super charger, but it had run for quite some time before switching to Royal Purple. His oil always felt thin and watery when we changed it and I hate that it's purple!!! Their gear oil also did horribly in a pretty big test article that I read a while back. I won't use any of their products.

GM started using Mobil 1 as factory oil when they came out with the LS1 and I'm sure they still use it in the LS2, LS3, LS7, and LS9...if it's good enough for an LS9, I'll take it :D
 
Croatan_Kid said:
GM started using Mobil 1 as factory oil when they came out with the LS1 and I'm sure they still use it in the LS2, LS3, LS7, and LS9...if it's good enough for an LS9, I'll take it :D
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They've ran Mobil 1 in corvettes since the introduction of the lt1
 
I have ran Mobile1 in my hot rodded cars since the early 90s never had any bearing failures and internals always looked great on tear downs. Running it in my LQ4 powered buggy now and would not consider anything else.
 
gary.h said:
They've ran Mobil 1 in corvettes since the introduction of the lt1
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Really? Huh...I never noticed it, but I also try to stay away from LT1s :shaking:
 
Croatan_Kid said:
Really? Huh...I never noticed it, but I also try to stay away from LT1s :shaking:
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I liked my LT1. It was solid, reliable, and made decent power stock. I had a 383 stroker in a 94 vette with the ZF6. They had slightly more power potential that a first gen SBC but unfortunately poor aftermarket support killed them. Technically, GM's short production run killed them, but the aftermarket didn't help.
 
Started my 2001 wrangler at 12,000 miles with synthetic and ran it till she hit somewhere around 190,000 miles and been running dino since.Got 227,000 miles on the clicker now.Developed the lifter tick around 170,000 miles.Fixed leaking valve cover and when I removed it,found built up crud on the front side of the rocker arm pillars.Now what I did was run the oil change for a length of 10,000 miles with 3 filter changes on it and the filters were Mobil One filters.I now change my dino oil around 4500 to 5000 miles and use Mopar's own filter.Now granted I use very very little oil during this interval and that might come from less ring wear from using the synth. but really don't know if it was really worth the extra costr for all these years.The dino oil appears to stay cleaner looking for a longer period.I also have very little seepage at the front and rear main seals.

Anybody know what to deo about this freakin tick other than turning up my radio?
 
4.0? Pull the head and put lifters in it....
 
It's not that bad! Me and a buddy put some lifters in his TJ one afternoon. A few hours, a few beers, an oil change, and we were out the door!
 
No....In 98' mercedes said put synthetic in everything and run them 10-15k before servicing. At 150k when we removed valve covers, on vehicles that had followed that schedule, it looked like someone had been adding potting soil to the motor from the amount of sludge build up. On other vehicles that petroleum based oil was used and changed every 3-5k the motors look new with over 300k on them. I can only speak from first hand experience of working on cars for 23 years so take it with a grain of salt. If the manufacturer calls for synthetic oil in the car, put it n a change it every 7k or sooner...if not run regular oil and change it every 3-5k depending on the type of driving you're doing and you'll be fine. The frequency of changing the oil seems to be what keeps things clean weather you use synthetic or petroleum based oils.
 
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