Switch from dino oil to syn?

TapouT

Well-Known Member
Joined
Oct 5, 2008
Location
Hickory nc
How many of you have made the switch from dyno oil to synthetic in an older vehicle with no ill effects? I recently bought a 2002 Toyota Tacoma 4x4 with the 2.7L 4 cylinder (3RZ). The truck has 186k miles on it and was a one owner. Bought it out of Hickory and it was always serviced at Mike Johnson Toyota in Hickory as per CarFax. I have no idea what oil they used in it as there's no receipts or anything. The truck doesn't use, burn or leak a drop of oil. According to the sticker, it's due for an oil change soon. Assuming it has dino oil in it, would I notice any ill effects switching to Mobil 1 Full Syn with a Toyota oil filter? I have a coupon for oil currently that will make the synthetic slightly cheaper than the conventional I was going to buy. Thanks for the help!
 
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Nope, should have no effects. Synthetic works great and protects really well, so should be good to go. Good synthetics also tend to clean things nicely, so you may notice some strangely colored oil after the first drain interval if there is any residual sludge from the old oil. That's the basis of the "synth causes leaks" myth. If you've got sludge plugging up a deteriorated/bad gasket and keeping it from leaking, synthetic oil may remove that sludge. So it can sometimes expose the existing problems that have been there for a long time. Shouldn't have to worry about that with a Toyota with a good service history, and any problems that are exposed are problems that are past due for getting fixed..
 
Fabrik8 said:
That's the basis of the "synth causes leaks" myth. If you've got sludge plugging up a deteriorated/bad gasket and keeping it from leaking, synthetic oil may remove that sludge. So it can sometimes expose the existing problems that have been there for a long time.
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On the whole I agree with this...similar to flushing a trans that hasn't been touched in 250k. However, I have seen some articles, that state there is some validity in synthetics resulting in leaks because it's a smaller molecule than the dinos. But again that would be a result of something being out of spec, be it tq spec, tolerance, wear, etc. That said, had a lot of hotties in my chemistry classes, so I have no clue if there's any truth to that statement.
 
I run synthetic in my 155,000 Yukon XL and 150,000 mile LJ. Both were bought with 125,000 miles on them and dino oil. No issues.

I wouldn't run synthetic in my old samurai, because that would just be wasting expensive oil, and it would probably leak more. It just gets whatever pieces of bottles are left on the shelf... ;)
 
I switched two of my trucks over one at 160k miles and one at over 200k miles. No problems. That tale and 3000 mile oil changes are two of the biggest lies in the automotive world....and a lot of people adhere to them like it's one of the 10 commandments.
 
I run rotella t6 in my 99 xj, no issues.
 
Croatan_Kid said:
That tale and 3000 mile oil changes are two of the biggest lies in the automotive world....and a lot of people adhere to them like it's one of the 10 commandments.
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That's something I've been telling folks for years. The engine doesn't care what's lubricating it as long as it's getting lubricated. Hell, I've run Type F for thousands of miles before. I have lit from the 50-70's showing recommended OCI's ranging from 12-30,000 miles. Fine old technology, they didn't know what they were talking about...how about a lot of newer cars owner manuals saying 7500-10,000 miles are acceptable OCI's depending on driving conditions. Sales tactic so you blow up your engine and buy another car, ok. What I can say is I have decades worth of oil analyses from Blackstone at 5k, 10k, 20k and a few at 30k. Regardless of type or brand of oil, they all have life left at 20k...25-30k seems to be where the oil gets too broken down to do it's job. And oil life seems to be way more dependent on filtration. So from trial and error, filter changes every 5-7k and oil change every 20k seems to be my sweet spot.
 
UTfball68 said:
That's something I've been telling folks for years. The engine doesn't care what's lubricating it as long as it's getting lubricated. Hell, I've run Type F for thousands of miles before. I have lit from the 50-70's showing recommended OCI's ranging from 12-30,000 miles. Fine old technology, they didn't know what they were talking about...how about a lot of newer cars owner manuals saying 7500-10,000 miles are acceptable OCI's depending on driving conditions. Sales tactic so you blow up your engine and buy another car, ok. What I can say is I have decades worth of oil analyses from Blackstone at 5k, 10k, 20k and a few at 30k. Regardless of type or brand of oil, they all have life left at 20k...25-30k seems to be where the oil gets too broken down to do it's job. And oil life seems to be way more dependent on filtration. So from trial and error, filter changes every 5-7k and oil change every 20k seems to be my sweet spot.
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Is that data with synethics or dino? I've never sent of oil for analysis. I typically just follow the suggested interval change plan in the owners manual. My wife's Pilot has a life % left on oil thing on the dash. I had never seen or heard of that before. I just change it when it gets below 10% life left. It seems to go about 10k miles between changes using 0W-20 full synthetic.
 
215k 5.3 here. I only run a sythetic blend oil with a quart of Lucas. Even to this date, I can change my oil at 8-9k miles and it's still very viscous.
 
drkelly said:
Is that data with synethics or dino? I've never sent of oil for analysis. I typically just follow the suggested interval change plan in the owners manual. My wife's Pilot has a life % left on oil thing on the dash. I had never seen or heard of that before. I just change it when it gets below 10% life left. It seems to go about 10k miles between changes using 0W-20 full synthetic.
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Both Dino's and Syns and some times blended. The key seems to be good filtration.
 
Only thing I have ever seen is that some oils are not backwards compatible. It may meet specs, but doesn't contain the same amount of minerals as older oils. I'd have to dig to find it, but I believe someone on here may have written it. East Coast Gear Supply also has good reasons for not switching to synthetic in his differentials.

Either way, engines running cleaner these days contribute to the oil lasting longer. Run whatever. Haha!
 
Thanks for all the replies. I just didn’t want to change it and this thing end up leaking out of every single orifice lol
 
If it springs a leak or more, you only out 1 oil change. You can change back. On Older engines, with weeping seals, & such, I use the dino-High Mileage oils. Stays in the engine longer!
As for Syn.s, I Do believe in them & use them! Only, after watching many YouTube videos on the subject, I'm disappointed to learn, that Full Synthetic, IS a Blend. WHAT? Yes, Only Synthetic listed as 100%, is Pure. Amsoil, is the best example. The Oil industry conned the Feds into letting us be Mis-Led. And, as with any oil, Not all synthetics, are equal. Look it up!
 
I'm planning to send in an oil analysis on my next oil change. I filled up the Duramax with Amsoil 15w-40 and an Amsoil filter. I'm planning to add a remote oil filter/bypass filter setup and then try out the 25k oil changes with analysis, of course. From everything I've read, a Duramax engine is very easy on oil and the bypass filter will help greatly in removing soot from the oil.
 
^^^Blackstone is $28/analysis. Amsoil offers an analysis too. Can't remember if it was $10 for the kit or $10 for the kit and analysis.
 
I believe the kits are free and you don't pay until you send it in to be analyzed.
 
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