Oil considerations? which to choose ??

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Hello, I am new here and looking for input on which oil to use synthetic or Con. I have heard a bit of mixed emotions regarding oil leaks developing after switching to a synthetic oil. I know you all have heard this same thing all the time on here, but maybe I can find a just answer. My truck has 130,000 miles on it (I just bought it) and am looking to switch to Mobil one. Is this a bad idea? My dad is also looking to switch, his car has 60,000 miles. Is it worth it? Should I even worry with this? What do you all think of the extended drains on the syn? like 15000 miles sounds crazy to me. I believe in staying with the man directions.
 
If you're not going to go past the mfg recommendations regarding oil change interval, then dumping more money on synthetic probably does not make much sense.

With that said, it may help if you tell us what specific vehicle make/model/engines you are talking about.
 
Use the viscosity GM recommends for your truck, it's in the owner's manual. There's no need to change to a syn at this point..personally (and this is sacrilege, so brace yourself!) I don't really see a need for syn in 99% of applications, it's mostly about marketing and 'Feelings', the actual wear reduction is inconsequential.

The truck might be new to you, so the desire to 'baby' her is understandable, but at 100k+, the advantages to syn are especially non existent, and you're right about increased leaks. Better to use a really good filter (I like PureOne) and change the oil at recommended intervals. Going 10k or 15k intervals with an engine not specifically designed for that is crazy, even with syn.
 
Thank You for the fast response, I think I will just use Castrol just like my other Silverado with 231,000 on it (when it caught fire due to a failed blower motor resister) Do you all think its pointless to use it in a 4 cyl camry also?
 
Use it if you want. Depends on the application, "Synthetic will Cause Leaks in a Older engine!!!11!!1!" is mostly untrue, its more like:
Synthetic will cause leaks in a poorly maintained/worn engine

That being said, I moved to synthetic at 120K-ish miles no issues!
 
Pointless to use a syn in a Camry?

It's a personal choice, but, again, if it's older, than I just don't see the point, it's not going to substantially prolong the life of your engine, all motor oils are just superb these days, and provide superior protection.

Castrol GTX is a fine brew with an excellent additive package, change it according to Toy rec's and use a good filter and you'll be fine. Just make sure it's the right viscosity.

I also have to respectfully disagree with the above comment that syn leaks "Only" in older or poorly maintained engines... As an engine naturally ages, the seals degrade regardless of 'Care', so leaks are not something you can accurately predict based on age or maintenance.
 
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Full synth and semi synth are all that has been put in UK market cars produced since the mid to late nineties.

Even stuff like London Taxis run a minimum spec of semi synth, but the handbook mentions the use of 10w40 semi synth or for better engine longevity and to increase cold start performance and fuel economy you can substitute for Full Synth with further options to run either a 5w40 or 0w40.

To be honest there also hasn't been any main stream manufacturer that has used a 3000 mile OCI for many years either.

However I think synthetics are more relevant to more modern engines with tighter tolerances, I know this doesn't apply to a lot of the big American V8 engines.

Interestingly the Chrysler Sebring 2.4 hatch only and PT Cruiser 2.4 both run full synth only in the UK. Unsure what OCI the Sebring runs but Mobil lists the PT as 20k km so about 12k miles.

I find it interesting how the same cars have very different specs in two different Countries, and also that despite the tiny cost of full synth (compared to the UK) in the US why anybody would run an inferior product.

Lets not forget that I am unusual in that I use full synth oil and also change a little early. Maybe I have a bit of OCD.

Or perhaps it is simply due to the ever tighter Euro emissions regs that have came into force in the EU since the late nineties?
 
If you want to use synthetic oil, there is no reason that you shouldn't.
If an engine isn't leaking on Castrol GTX, it isn't likely that a sythetic will suddenly open up leaks.
Way back in the day, this might have been true, but not now.
Also, open your mind a bit.
There are many quality synthetic products out there beyond Mobil 1. You could use Quaker State Ultimate Durability, for example, at a cost that would hardly be any greater than GTX. You'd get better cold temperature starting performance in return, as well as lower NOACK volatility and a higher viscosity index. This oil also meets the old GM 4718M spec, which GTX can't hope to meet.
This is an indication of the quality of the basestocks used as well as the additive package.
You pay more for a synthetic oil, but you also get more.
You don't pay a whole lot more, either.
 
Increased oil leaks by switching to synthetics from everything I've seen and read is pretty much no longer a problem. If the motor is so poorly maintained that it has a sludge seal keeping it from leaking, you have more trouble than a few leaking seals. That said, I switched my 96 at 130k miles to Mobil 1 and then to SynPower, and latest oil change of PP...I have no major oil leaks still at 216k miles.

If the car or truck sees mainly highway miles, I feel this is a time where synthetic can shine. Mobil 1 or Mobil 1 EP could be good for 10k mile OCI interval. I would hazard a guess that provided the PCV system and the motor are in good shape, an OCI of 7500-10k should be possible and maybe longer. A UOA would help confirm OCI.
If they see a lot of around town duty, then a conventional would be just fine. The oil is going to have fuel and condensation contamination and need to be changed sooner. Hope this helps you out!
 
People seem to think Syn oils are thinner than conventional,thus will slip past seals far easier.I dont think a 5/30 syn is any thinner than a 5/30 conventional,and I believe the syn oils got the bad rap decades ago when they lacked proper seal swell additives.
 
I switched to synthetic oil at 235,000+ miles and have not had any leaks form. That was 11,000 miles ago.
 
Go with PP from Walmart. Its a decent price, easy to get and an excellent oil. You should not get leaks changing to synthetic assuming you are taking reasonable car of the vehicle. On the outside chance you get a leak, it will probably go away on its own as the seals gets better conditioned.
 
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