switch back & forth from synthetic to regular oil?

[MAXRN]

hey all, was at the shop the other day and I over heard a conversation between a mechanic and an owner of a subaru imprezza: owner uses synthetic for winter and regular oil for summer. I thought that once you switched to sythetic you shouldn't go back to regular oil?

PS: is time to flush out my brake fluid at 105K (KM's)?

Thanks in advance for your input.

[anomaly117]

Originally Posted by MAXRN

hey all, was at the shop the other day and I over heard a conversation between a mechanic and an owner of a subaru imprezza: owner uses synthetic for winter and regular oil for summer. I thought that once you switched to sythetic you shouldn't go back to regular oil?

PS: is time to flush out my brake fluid at 105K (KM's)?

Thanks in advance for your input.

as long as your brake pedal stills feels nice and hard you dont need to flush it. its pretty well sealed off and shouldnt ever get air in it or get dirty.

as for synthetic/conventional oil switcheroo, oil all does the same thing IMO. if its a daily driver. dont worry about it. i just use the cheap stuff. if you track the car, you should stay faithful to one "high performance" oil.

[Love_00_Max]

Bleeding every 30K miles will keep the calipers healthy.. choose syn brake fluid.

[SangH]

Your engine wont care what oil you put in it. Just make sure you fully drain it before switching.

As far as switching between regular and synthetic in relation to season...I don't know about that...seems pointless to me. Switching to a lighter weight of the same brand during winter to reduce cold start wear sounds more beneficial.

[MAXRN]

Thx for the info.

[ghostrider17]

Originally Posted by anomaly117

as long as your brake pedal stills feels nice and hard you dont need to flush it. its pretty well sealed off and shouldnt ever get air in it or get dirty.

This is SO WRONG on so many levels....

Don't post-up information like this if you don't know what you're talking about -- it is SO misleading.

Brake Fluid is hygroscopic, which means it DOES and WILL absorb water in molecular form.
Water in brake components is bad. VERY BAD!
Most modern hydraulic braking systems are indeed well sealed, but they are NOT 100% airtight.
If they were you'd NEVER have to change your fluids.
Rubber seals wear-out, and air/water DOES invade the system.

Follow your maintenance schedule for bleeding brakes - it's not that tough, and/or expensive.

--------------------------------

As for switching Oil:

ALL Oils are NOT created Equally -- do some research, and focus on Additive pkgs, and BASE STOCK oil from which the oil formulation is derived. The information IS Dizzying...so if you want the short-version, just go with the majority: Mobil1 is wildly popular, AMSOIL is damn good, and so on....
I've never found any scientific proof, but it is GENERALLY accepted that you should NOT switch between dino and synth.
Pick one and stick with it.
Synth DOES have overall superior cold start properties over dino given it's lubricity and molecular bonding to metal parts....but this also applies to hot weather and shearing factors at high temps.
Best of both worlds.
Ask ME why I use it?!

If you choose to go with dino, stick to a 3-5k OCI (oil change interval) depending on how you drive between OCI's.
CHoose a better than OEM oil filter also -- don't CHEAP OUT! Wix, Purolator PUREONE...etc.

Contact Talkinghorse via PM....he'll set you straight.

gr

[Christobal65]

Originally Posted by ghostrider17

ALL Oils are NOT created Equally -- do some research, and focus on Additive pkgs, and BASE STOCK oil from which the oil formulation is derived. The information IS Dizzying...so if you want the short-version, just go with the majority: Mobil1 is wildly popular, AMSOIL is damn good, and so on....
I've never found any scientific proof, but it is GENERALLY accepted that you should NOT switch between dino and synth.
Pick one and stick with it.
Synth DOES have overall superior cold start properties over dino given it's lubricity and molecular bonding to metal parts....but this also applies to hot weather and shearing factors at high temps.
Best of both worlds.
Ask ME why I use it?!

If you choose to go with dino, stick to a 3-5k OCI (oil change interval) depending on how you drive between OCI's.
CHoose a better than OEM oil filter also -- don't CHEAP OUT! Wix, Purolator PUREONE...etc.

Contact Talkinghorse via PM....he'll set you straight.

gr

While there is some good info in here there is a lot missing mainly that most synthetics aren't actually synthetic. Most of the 'synthetics' from companies like Mobil 1, Castrol, Valvoline and Penzoil are made using what is called a Group III base stock which is actually a dino or standard oil base stock. A true synthetic uses a Group IV or Group V base stock (Royal Purple is Group IV and oils like Redline and Amsoil are Group V). Now that being said Group IV and V oils arent really needed for maximas that are still running NA.

As for Mobil 1 (M1) being good well its not so great anymore. In the last 3 or so years they switched from using a Group IV base stock to a Group III but still charge the same price. Generally most performance forums who have done UOA (Used Oil Analysis) on M1 show that its now a rather poor choice of oil for the price. It's known to shear from a 30wt oil to a 20wt oil after as few 1500mi.

My Recommendation is to use a Heavy Duty Engine Oil (HDEO) such as Chevron Delo 400 or Shell Rotella T. HDEO's offer a much better additive package that offers better protection and longer oil life. The UOA I just got back on my Delo 400 showed that i could easily go 5300mi and i wasn't easy on the car.

Its also important to note that it will take 1-2 OCI (Oil Change Interval) to actually fully switch out the oils. Can you switch sure you can switch all you really want to and it wont cause much if any of a problem short from the possibility of a minor oil leak for the first few OCI going from dino to synthetic