from dino to synthetic blend

[tonttu]

my car is firebird 92 112500 miles on it.i was thinking to switch my oils from dino to synthetic blend?should i be worried that my seals start to leak?

[BobbyZ72]

you can switch...that about the leaks starting is the biggest myth. ;)

[SpeedingFirebird]

It is not a myth. Stick with dino.

[95 camaro]

It doesnt cause leaks, it just takes all the crap out of your engine and shows where they are. Every high mileage engine so far that I have switched from dino to sythetic has started to leak, but ive only had 3 cars so mabye it was just bad luck. My last car the intake manifold crapped out.

[PalmHarborBlkv6]

I have a 2000 3.8 and have been using Mobil 1 since new.
No problems......go ahead..........keep your receipt and if
it leaks......write letter to Mobil and demand money back
or damages, but I suspect U will be fine...just fine.

[Turbo V6 Camaro]

fit go go synth and you get leaks the leak was already there the syn oil cleans better, and dont leave crap behind like reg oil does..... so reg oil plugs up its own hole, the synth oil clean the hole and escapes

[tonttu]

prewious owner that had the car before me,has been using shell helix plus 10w40 synthetic blend at least twice.but i have been using dino oils about two years now.that should lower the risk that seals start to leak,right?and what about sludge or deposits?should i change oil and filter earlier,just to make sure that it dosnt block my engine or oil filter?i have been changing always my oils after 3000miles.and what about "sae" letters behind the oil bottle?what those "sae" letters mean,does anyone know? :rolleyes:

[terminaldegree]

SAE = society of automotive engineers
They are the people who certify the standards for oil viscosity [like 5w-30, 10w-30].

If your car has leaks now, or a lot of seals "weeping", then I would advise against the synthetics. If not, go ahead and switch.

You are obsessing over the oil thing TOO MUCH. Just relax and put something in. 5-30, 10-30, dino, semi syn, synthetic, whatever, it isn't going to make a huge difference with 3,000 mile oil changes [or shorter] and normal driving.

Now go out there and drive your car...

[tonttu]

should i only buy oils that have sae letters? :rolleyes:

[SpeedingFirebird]

Originally posted by PalmHarborBlkv6:
I have a 2000 3.8 and have been using Mobil 1 since new.
No problems......go ahead..........keep your receipt and if
it leaks......write letter to Mobil and demand money back
or damages, but I suspect U will be fine...just fine.

dude, he's talking about a car w/ 112K miles on it. [img]graemlins/slap.gif[/img] Yes, starting from new Synth is great.

As already stated, synth runs cleaner and may remove contaminents that are plugging leaks. At 112k, you are asking for trouble switching. It is not a myth.

[FunkZ]

Bah, I bought the car with 45k miles, switched to a blend for 100k miles, and started using the new Mobil EP for the last 16k. Never had a leak. And I've even run Seafoam through my crankcase, so if there were any "contamanents blocking up leaks" they would be washed out by now.

If you're using the same weight, it shouldn't matter if it's conventional or synthetic. The difference is the synthetic doesn't break down as quickly, so it lasts longer.

[CDNFB]

I don't think you can by an API approved engine oil without SAE grading. If it doesn't have API and/or SAE stay away from it!

I bought my car at 80k and know it had never seen synthetic, and like FunkZ I Changed to synthetic and never had a problem with leaks or anything.

If there is enough sludge, varnish build up, sediments, or whatever, in an engine in enough quantity that it prevents oil leaks, I would say that the leaks are the least your problems! And if a synthetic oil was enough to start such a leak, so would a high quality AD (ashless dispersent) oil with crammed with all sorts of detergents.

NEVER use synthetic on a new engine or on a newly rebuilt engine. An engine needs to be broken in before using synthetic oil. This is because synthetic oil seriously reduces friction and wear to the point were the piston rings will not properly wear in and seal against the cylinder wall. When asked I have always recommend using mineral oil for the engine break-in (approx. 20K miles)period, then switch to synthetic.

I agree that you can over-think this oil thing. Don't sweat it, your engine will endure for many, many, many more miles by using the dino oil as long as you drive your car within reason and religously change your oil at the proper intervals. If you start to stress your engine beyond its original design criteria (Severe duty driving (I'm talking autobahn for hours here and not the occasional "to the floor boards-full pull"), or incorporate high output mods) then you need to think about this a little more.

[tonttu]

i have seen shell helix plus oil in sweden and shell helix ultra, and super=(dino) oil.and they dont have sae letterings.like example;shell helix plus,api sl/cf but it dosnt have sae letterings.

[Turbo V6 Camaro]

Originally posted by CDNFB:
NEVER use synthetic on a new engine or on a newly rebuilt engine. An engine needs to be broken in before using synthetic oil. This is because synthetic oil seriously reduces friction and wear to the point were the piston rings will not properly wear in and seal against the cylinder wall. When asked I have always recommend using mineral oil for the engine break-in (approx. 20K miles)period, then switch to synthetic.

that two is also a myth...... i used syth oil since the frist start up in my car and everything is fine..... and no motor breaks in for 20k miles that i know of....

i check my compression th other day and they was all 145-150... syn oil breaks in motors just fine... guess what comes in vette's viper's and many other cars form the foactory? mobil 1 synth oil

[SpeedingFirebird]

Originally posted by FunkZ:
Bah, I bought the car with 45k miles, switched to a blend for 100k miles, and started using the new Mobil EP for the last 16k. Never had a leak. And I've even run Seafoam through my crankcase, so if there were any "contamanents blocking up leaks" they would be washed out by now.

If you're using the same weight, it shouldn't matter if it's conventional or synthetic. The difference is the synthetic doesn't break down as quickly, so it lasts longer.

that's 45K. dude is talking about 112K. The cutoff I typically here is around 70K you *could* develop leaks. Yes, numerous people do not get leaks. However, you increase the probability of introducing a leak.