Brother inlaw says switching from synthetic to regular oil will blow the motor

[greenpigs]

I think he is off his rocker, as long as you use the same type 5W 30 regular or synthetic doesn't matter as far as an engines concerned.

[Tilar]

Brother inlaw says switching from synthetic to regular oil will blow the motor

Only if he tries to change it without shutting the engine off.   

[dukeboy_318]

wow, hes way off the mark, ive used one or the other, depending on my cash on hand at the time, usually i use syntheic blends for the winter, regualr oil for the summer in my truck, no problems yet, been doing that for 6 yrs.

[moparguy01]

I value my lawnmower, so we'll go with "not gonna let him touch my mower"

[chargerboy69]

I have heard if you have always run regular oil, and your engine has a lot of miles on it, do not start to use synthetic in that engine. I have heard that from several mechanics.  I was just told that by a ASC BMW mechanic this last week. I am looking at a BMW with higher miles on it, and that is what he told me.

[doctorpimp]

I have heard if you have always run regular oil, and your engine has a lot of miles on it, do not start to use synthetic in that engine. I have heard that from several mechanics.  I was just told that by a ASC BMW mechanic this last week. I am looking at a BMW with higher miles on it, and that is what he told me.

That's an urban myth.  Every mechanic has their own point of view on synth oil.
The advantages to using synthetic oil are: Extended oil change interval, Does not thermally break-down, More HP due to less friction compared to dino oil at same viscosity. 
I changed from regular to synth in my 1992 Ford Probe V6 when I bought it used, 5 years old with 60,000 miles on it.  I drove it for another 6 years and 90,000 miles before I sold it - still running strong.

If you change from synth down to reg, just ensure that you change your oil more often (about 1/2 the interval of synth)

[AMX GO PACK]

Does he have a mullet by chance ?

[The70RT]

Everyone says viscosity is viscosity.....but I seen cases where you get leaks if you start using syinthetic after using conventional.

[greenpigs]

Does he have a mullet by chance ?

He is working on it.

[restoman]

Everyone says viscosity is viscosity.....but I seen cases where you get leaks if you start using syinthetic after using conventional.

That's a myth as well. Synthetics don't cause leaks. They will leak out faster if the seals and gaskets are already compromised (leaking), but they do not cause leaks.
I'd love to use synthetic in my Beetle, the air cooled mill would love it, but it would leak out faster than I could put it in.

I've been using Amsoil in all my cars for 6 years and have had absolutely no problems. My 89 Corolla had 230k on it when I switched it to synthetic - it's still going with a different owner at 275k.
Top synthetic oils like Amsoil or Mobil 1 are better in every way than the top Dino oil.

[Tilar]

That's a myth as well. Synthetics don't cause leaks. They will leak out faster if the seals and gaskets are already compromised (leaking), but they do not cause leaks.

Exactly. Synthetic generally has more cleaning agents and what happens is it cleans the sludge off from shafts and seals. I'd say if you are worried about that to add a little Sea Foam and see if some of those seals can be softened back up.

[ITSA426]

Can you just change brother in laws?

[beedees]

Dumb question time...what exactly IS syn. oil made from? 

[The70RT]

Everyone says viscosity is viscosity.....but I seen cases where you get leaks if you start using syinthetic after using conventional.

That's a myth as well. Synthetics don't cause leaks. They will leak out faster if the seals and gaskets are already compromised (leaking), but they do not cause leaks.
I'd love to use synthetic in my Beetle, the air cooled mill would love it, but it would leak out faster than I could put it in.

I've been using Amsoil in all my cars for 6 years and have had absolutely no problems. My 89 Corolla had 230k on it when I switched it to synthetic - it's still going with a different owner at 275k.
Top synthetic oils like Amsoil or Mobil 1 are better in every way than the top Dino oil.

If it leaks out faster that must mean if it is almost has a leak it will get one. I seen several cases where there wasn't a leak and then a leak showed up. That IS MY experience I have had. Plus in an older engine you will use more if your using any at all......been there done that.  It also has the potential on some older pushrod race engines with roller lifters for the roller itself not to spin with camshaft movement, but rather slide while the roller itself remains either stationary or at a lower circumferential speed than that of the camshaft lobe.

Dumb question time...what exactly IS syn. oil made from?

Synthetic oil how made:
Fuels, Synthetic, liquid or gaseous fuels extracted or fabricated from solid earth materials that are rich in hydrocarbons—compounds containing hydrogen and carbon. Although similar in composition to gasoline, synthetic fuels are not refined from petroleum, but are extracted instead from coal, oil shale, tar sands, natural gas, and biomass (plants and plant-derived substances). For example, coal can be converted into liquid fuel by a process called liquefaction, and oil can be extracted from oil shale by a process called retorting. Natural gas is converted into fuel-ready liquid by using gas-to-liquids technology.
Encarta Encyclopedia

[PocketThunder]

synthetic or regular i could care less, whatever you do piggy, NEVER change your Avatar!!!!                                     

[nh_mopar_fan]

synthetic or regular i could care less, whatever you do piggy, NEVER change your Avatar!!!!                                     

Yeah, but I miss the "just lick it" one. always made me chuckle.

One more time, please?

[greenpigs]

 

Only for a few days...mkay.

[nh_mopar_fan]

hee hee hee

[Spike]

Can you just change brother in laws?

But seriously, so many opinions about synthetic oils.
Like mentioned already, synthetic oils have more detergents. If you have an oil leak after changing to syn oils, the leak was there before. It was just plugged up with sludge.
High mileage engines can be changed over to syn oils, a good engine flush and monitoring for any oil leaks or excessive usage would be wise.

Other than extended mileage between oil changes, syn oils offer better cold temperature protection, a lower boil off rate, better oxidation protection along with other benefits.

[doctorpimp]

But seriously, some many opinions about synthetic oils.
Like mentioned already, synthetic oils have more detergents. If you have an oil leak after changing to syn oils, the leak was there before. It was just plugged up with sludge.
High mileage engines can be changed over to syn oils, a good engine flush and monitoring for any oil leaks or excessive usage would be wise.

Other than extended mileage between oil changes, syn oils offer better cold temperature protection, a lower boil off rate, better oxidation protection along with other benefits.

[A383Wing]

The biggest trick with the used car lots is to put synthetic oil in the cars they are trying tp sell....if the car burns oil, it won't emit the "blue" smoke with synthetic.....

I'll stay with the regular oils....the cost of synthetic does not measure up to the so called added mileage that everyone says yer supposed to get.

Bryan