Switching from regular oil to synthetic?

[DSM1290]

My friend told me that a mechanic said not to switch to synthetic oil in this Explorer b/c the regular oil and the synthetic would not mix and mess up his engine. Is this true? He also said with Seafoam you should change your oil and add it in. And run it in there for the full 3000 miles before you change it out. That didn't sound right either to me. Any one with knowledge on this please let me know what you think.

[Fubar231]

All i know is (From what i experienced) if you go from regular dyno oil to synthetic you may spring some oil leaks. If old gunky oil is holding the gasket together, and some good synthetic oil runs by and cleans it out... well... you get the idea.

 

On the seafoam part, seen it done, dont trust it, would never do it to my car.

[Slimpsy1647545505]

If you got a high mileage car that's always ran conventional oil, I would not recommend switching over to a fully synethic oil. . but perhaps a high mileage blend.

 

synthetic lubricants offer several benefits over regulars :

1. less engine damage at startup

2.less variation in lubrication properties of the oil over temperature variations.

3.more detergent to keep engine clean.

 

However in older engines, some burning may occur,if the valve seals are corroded. The detergent in the synthetic oil will remove the sludge and get leaked.

 

Other than that, it will be beneficial to your cars engine to use a synethic blended oil :-D

 

And I agree on the seafoam stuff, would not trust it.

[Buck531]

Not sure on the synthetic stuff. I changed all the gaskets on my motor before I started using it in the Buick.

 

As for seafoam. It works. I sure as HELL wouldn't put it in my oil and run it for 3k. You might as well start looking on car-part.com for a new motor. Run it through your vac line and suck it in until the car stalls. Let it sit for 1/2 hour, drain oil, change plugs and start car (it'll be a bitch to start) and then watch the smoke screen kill your neighbors trees.

[Fubar231]

As for seafoam. It works. I sure as HELL wouldn't put it in my oil and run it for 3k. You might as well start looking on car-part.com for a new motor. Run it through your vac line and suck it in until the car stalls. Let it sit for 1/2 hour, drain oil, change plugs and start car (it'll be a bitch to start) and then watch the smoke screen kill your neighbors trees.

 

Definitly sounds much better than letting it sit in your oil for 3,000 miles (a few months). Like ive said ive seen it done, and that smoke screen is 1 hell of a smoke screen. Might as well fog the the neighborhood while your at it.

[Richard Cranium]

I've been told never to run an oil treatment. The crap does get cleaned out of the oil passages and the engine does get cleaned up. But all that crap ends up in the oil, and then in the screen of the oil pickup. Once that screen plugs up you can say goodbye to your motor when there is no more oil pressure.

[CRed05]

Old wives tale...you can mix engine oils as much as you want. I'm also not a fan of oil treatment because oil is good enough as it is. If you have a high mileage vehicle and you are concerned about keeping the engine clean and keeping the seals in good shape, start using a high mileage oil like Valvoline's Maxlife, its available in a semi or full synthetic so it lubricates well, has added detergents to keep it clean, and additives to restore engine seals.

[SpaceGhost]

Hell Mobile 1 is not really synthetic anymore anyway right?

[dakotart]

I ran conventional oil for the first 12,000 miles and then switched to Mobile 1 synthetic.

 

I have not had any problems.

[excell]

You know, I've read on forums for years about high mileage engines switched to synthetic potentially having leaking/burning/etc. issues and I just don't believe it's a normal occurrence. Here's my experience:

 

1988 Mustang 5.0 switched at 155k.

1998 Grand Prix GTP switched at 98k.

1996 Explorer 4.0l switched at 132k.

1999 F250 5.4l switched at 109k.

2004 Saturn Ion 2.2l switched at 64k.

2002 Trailblazer 4.2l switched at 54k.

 

None of these vehicles burned/used more oil after the switch, nor did any "new" leaks happen. In addition to these I've overseen several other vehicles over 100k switch to synthetic with the same results. I'm not saying that negative results don't happen, but I believe negative results to be the outlier and not the rule.

[Cordell]

If you're worried about synthetic causing a problem then don't use it. The only potential problem with it is loosening something or causing old seals to leak, if the engine's condition is in question then why would you spend extra money on synthetic? I personally use synthetic a lot, but have switched back to a high mileage on my wife's car because it got to over 120k.

 

DO NOT PUT SEAFOAM INTO OIL!! This is stupid and in my opinion if you feel you need seafoam in your oil your engine needs rebuilt.

Edited November 6, 2009 by Cordell

[SicShelby]

I'm not a certified mechanic, but I can't imagine blowing a gasket because you switched to synthetic. I've honestly never ran "non"synthetic oils in my cars before. I feel a man-made blend can be tweaked to do more things than a standard oil.

 

As for the sea foam... yep run it though the intake. Just... don't get into the habit of using it often. When the Yaris turned 100k I ran some through and it smoked for a good mile or two (that's the best part lol) and I'm calling it good probably until the engine stops...

[Billiumss]

You know, I've read on forums for years about high mileage engines switched to synthetic potentially having leaking/burning/etc. issues and I just don't believe it's a normal occurrence. Here's my experience:

 

1988 Mustang 5.0 switched at 155k.

1998 Grand Prix GTP switched at 98k.

1996 Explorer 4.0l switched at 132k.

1999 F250 5.4l switched at 109k.

2004 Saturn Ion 2.2l switched at 64k.

2002 Trailblazer 4.2l switched at 54k.

 

None of these vehicles burned/used more oil after the switch, nor did any "new" leaks happen. In addition to these I've overseen several other vehicles over 100k switch to synthetic with the same results. I'm not saying that negative results don't happen, but I believe negative results to be the outlier and not the rule.

 

 

Some how you got VERY lucky.

 

I switched on 2 cars, one was a 1994 GP (60k miles) with a 3.1L and the other a 1992 Z34 (80k miles) DOHC 3.4L and both leaked oil after switching, happened within 5k miles of switching oil. Both cars were clean before.

[Cordell]

Some how you got VERY lucky.

 

I switched on 2 cars, one was a 1994 GP (60k miles) with a 3.1L and the other a 1992 Z34 (80k miles) DOHC 3.4L and both leaked oil after switching, happened within 5k miles of switching oil. Both cars were clean before.

 

I mean no offense Bill, but both of those engines suck, bad. They are two of GM's poorest designs and are very prone to leaking oil and coolant regardless of what you do to them. My parents had a 3.1 that had to be repaired under warranty for leaking (25k). Unfornuatly you just didn't have great cars to try this on, do you really put conventional oil in your Camaro?

[AWW$HEEET]

seafoam is the shit.

[s13]

Switching from regular to synthetic is fine. When you switch from a synthetic (mostly high milage) that has seal swellers in it and go to regular you will piss oil out.

[DSM1290]

If you're worried about synthetic causing a problem then don't use it. The only potential problem with it is loosening something or causing old seals to leak, if the engine's condition is in question then why would you spend extra money on synthetic? I personally use synthetic a lot, but have switched back to a high mileage on my wife's car because it got to over 120k.

 

I'm not worried about it, it is for my friend. I just thought the mechanic that told him he couldn't mix the two was dumb. I didn't see how it could possibly fuck up your motor. And if synthetic "cleans" out sludge and would then block up the engine, would the GTX "anit-sludge" do the same thing?

 

But the main question was can you mix them and/or switch without any mess ups.

[gillbot]

I switched my old truck at 200k and had no problems and many other high mileage switches went well. If you are concerned, try a synthetic blend first and see how well it works.

[Cordell]

I'm not worried about it, it is for my friend. I just thought the mechanic that told him he couldn't mix the two was dumb. I didn't see how it could possibly fuck up your motor. And if synthetic "cleans" out sludge and would then block up the engine, would the GTX "anit-sludge" do the same thing?

 

But the main question was can you mix them and/or switch without any mess ups.

 

Putting any oil into your engine is fine. There really are no proven facts about any of the opinions posted in this thread. All oils are at some levels synthetic anyway, just like all of them have some level of cleaners in them. Sludge clogs up engines on it's own, though certain things accelerate this process (like seafoam) but the sludge already has to be in the engine. If people use modern oil and change it regularly sludge won't form in the first place. The really funny part of all this is that in decades past like the 50s, 60s, and 70s motor oil was crap for the most part and sludged regardless. Quaker State is one that comes to mind for having had losts of waxes and parifins in it when it first came out 50 years ago more so then others at the time. Everything sludged and people produced different cleaners, keep in mind that engines didn't last nearly as long back then, and sludge was a huge concern. Fast forward to today with modern oils (everything on the shelf) with parts of them synthetic, having cleaners in them, and being less likely to break down you just don't have the problems that people still talk about. Cleaners that used to be needed aren't needed anymore, but people still sell them because of the old time way of thinking. Everything has advanced, and unless your car has been outright neglected I seriously doubt that there is any sludge in it what so ever. Like I have stated earlier if you have a sludge problem, the engine has been neglected and there is no easy fix. If you think you can benefit from synthetic then put it in the car, it will free up a few horsepower causing the engine to run more efficently, better gas mileage, and longer lasting oil, how much so is a matter of opinion. To what degree you use synthetic really doesn't matter. I have agreed with some arguements about synthetic helping to get leaks going, but I also think that those leaks would have started eventually anyway. It's my opinion that synthetic doesn't hurt anything in anyway you use it, if there was they'd put a disclaimer on the bottle. If any of these opinions on synthetic could be proved people would have sued somebody by now.

[gillbot]

All oils are at some levels synthetic anyway, just like all of them have some level of cleaners in them.

 

Depends on if you use the term "synthetic" properly. Most oils today are modified hydrocarbons, not true synthetics. Amsoil and Royal Purple are "true" synthetics, most typical brands are not.

[Cordell]

Depends on if you use the term "synthetic" properly. Most oils today are modified hydrocarbons, not true synthetics. Amsoil and Royal Purple are "true" synthetics, most typical brands are not.

 

I don't think you got what I meant, all oils, conventional or synthetic, have synthetic properties to them. Let me also say that I am no chemist and just stating what I beleive to be facts based on conversations with people who are chemists and represenatives of oil companies, with a little of my opinion mixed in there for good measure.

[AWW$HEEET]

I wonder how Valvoline or whoever is saying now that if you switch to their brand, they will insure your motor up to 300k miles...

[Cordell]

I wonder how Valvoline or whoever is saying now that if you switch to their brand, they will insure your motor up to 300k miles...

 

There is a lot of paperwork involved, and very accurate records must be kept to show when and what was changed. That is one of the reasons documentation is very important when operating a shop.

[Rotarded1647545491]

The only "concern" I have seen with switching from Dino juice to synthetic oil has been with leaks. If you are leaking oil using regular motor oil, you will leak at a larger rate with synthetic. The smaller molecule size and penetrating properties of synthetic oil make leaks worse.

 

 

I wonder how Valvoline or whoever is saying now that if you switch to their brand, they will insure your motor up to 300k miles...

 

"Depending on the type of oil you choose, you can get a guarantee between 150,000 miles and 300,000 miles, the car must be a 1990 model or newer, you must sign up with no more than 75,000 miles on the odometer, engine oil viscosity and fill level must match the manufacturers specifications, you or a qualified Valvoline oil change station must do the work, including new filter, at 3000 miles intervals with a 1000 mile grace period (so up to 4000 miles between changes), you must register the date of changes and keep all the appropriate receipts. You do have to do regular scheduled maintenance as suggested by the manufacturer as well. That's pretty much it. If the engine fails somewhere along the way and under Valvoline's guarantee, they'll pay up to $5,000 to replace it.

 

Considering it takes most Americans 25 years to put 300,000 miles on a car (and the program only lasts till 2029), you can screw up on any of the conditions a few times, but overall, it seems like a pretty darn solid proposal. Of course, most Americans don't keep their cars for 300,000 miles and certainly don't change their oil or keep records with the religious zeal necessary to keep up on the requirements, but still, not too bad since you'll be changing your oil anyway.

 

And no, you cannot go racing with this guarantee, we thought the same thing."

[87GT]

I only put seafoam in an empty gas tank then fill up with fuel. That is supposed to help with dirty fuel injectors. The only oil treatment I did was with Marvels Mystery Oil. My saturn that had a piece of shit high mileage dohc I4. It burned 1 qt of oil every 1000 miles. With the treatment I did each oil change I got it down to only burning a 1/2 qt every 1000 miles. This took 5 oil changes to happen though...

 

But if you want to do it get a normal size bottle not a large one of MMO. Do this right before you want to chain your oil normally. Take out all the spark plugs and put in 1-2 oz in each hole. Plug each hole up with a shop towel. Dump the rest of MMO in your oil. Close your hood and go to sleep. Next day start the car and turn it over so it blows out the towels. Then stuff them up again and turn it over just another second. Then put your plugs back in and drive the car. It will smoke a lot for a few minutes but after it stops smoking park the car and change the oil. Wait 3000 miles then rinse and repeat.