hi guys, so my 99 es 300 has 79,000 miles and from receipts i"ve deduced that it had always run regular oil, im wondering if i switch to mobile one synthetic will i mess anything up or will all be good?

 

nothing wil be messed up. but most likely, if the rear vcg isn't leaking enough to notice, it might be a little more noticeable. but that wouldnt be the oils fault.

mobil 1 synthetic is not a bad oil in general. but the diferent versions and weights are very dif in their specs. which one in particular were you after, for ex, mobil 1 10w-30?

its probably better slightly to stick with high quality conventional though in your car's case. consider changing it every 3 to 5 K miles to avoid sludge. if you do synthetic, its harder to say but generally you should be fine 5 to 10K miles, even longer is possible but hard to predict with oil analysis and peeking at the valve train for a hint at sludge.

why do you want to sw to syn to begin with?

 

I'm changing because of what i have read its the best thing for the car? I run syn in my harley, cant say I've noticed any difference , but all i hear and read is that it will prolong the life , i also like the thought of extending the life of the oil , i usually change every 3thousand or so but i only put 10k a year on my car , i don't relish the thought of creating a leak by going with syn ???

 

I also am thinking of switching to syn in my ES as I just recently did in my RX. I am confused:
-Should I be concerned with some of your thoughts on vcg possible leaking. What is that and why may it be more noticeable with syn vs. conventional? Is that because of sludge from conventional slowing the leak?

 

Do you currently have any oil leaks?

1: If yes, the Syn oil may make it leak worse, fit the oil leak then switch to Syn.
2: If no, just go ahead and switch.

I use Syn in both my car (Boost '96 1MZ) and my mom's car (Stock 2AZ-FE Camry).

 

Why does synthetic make an existing oil leak worse?

 

Syn often cleans out the engine as it;s a better oil. It also tends to be thinner (smaller molecules I think????). So if there is an oil leak, it will likely have crude and dried oil where itls leaking from, so the Syn oil will "clean" it, and open op the leaking area. I'm sure thats not the best way to describe it, but not sure how to better, sorry.

 

Thanks, that is what I assumed.

 

-Amaterasu
I found myself in a similar position just weeks ago on this topic. Daily driving a 1998 ES300 with 68K miles which has had conventional from the start, I thought about making the switch as well. I spent countless hours researching on the web due to all the pros and cons I've heard about changing over to synthetic oil. Tons of info. is here on ClubLexus if you conjure up a quick search. IIRC 'Lexmex' has some great knowledge about this topic too. You could also go to Bobistheoilguy.com

I guess your biggest concern as noted in your post is if the change to synth will cause leaks/damage to your engine. Regardless of synth or dyno, oil is made to run in engines and shouldn't do any mechanical harm as long as your engine was in healthy shape to begin with. Leaks on the other hand are slightly different since many people argue whether synth causes leaks or just makes small ones more apparent than before. Only you or your mechanic really knows about the condition of the gaskets/seals (valve cover/rear main/cam/crank seals)in your car which plays a large factor in any possible leaks that could occur. You should also take into account the age of your car which leads me into another point.

Your car being at 79k ~10 yrs old tells you that the conventional oil has worked perfectly fine for your vehicle and the millions of other cars on the road using conventional as well. If you decide to switch and start leaking(not trying to scare you), keep in mind that you will need to have many of these seals replaced at the 90K service interval anyways. On the otherside, many people that have switched have experienced overall smoother engine performance in the long run.

Well after all that reading, I guess i'll post my experience. I scratched my head for days trying to decide. I chose to go the halfway route and run a synthetic blend instead of full synthetic to see how things go. I'll keep my eye on things and if it's a green light, i'll switch to full synthetic for the next change. 1 jug of Mobil 1 by me is $19

But the most important thing is staying on top of oil changes for your car or any other car for that matter. (Your engine is the 1MZFE which is known to sludge if neglected) Regardless of synthetic or conventional, changing the oil and using clean oil is the key idea to prolonging the life of your car.

Hopefully this answers some of your concerns.
Oh, also welcome to Club Lexus and thumbsup for the low mileage ES. It's a great place and I learned most of this information by reading through countless threads on CL.

 

well the key is to have oil with high temp resistance for breakdown, so mobil 1 is better at that than many conventionals, so i recom mobil 1, but i wanted to know what got this person interested. marketing? a problem with car he assumed would be fixed by mobil 1? see where I'm going?
but yeah, sw to mobil 1 will be AOK. I use mobil 1 0w-40, the one loaded with valve train protecting zinc because the chances of catalytic converter damage is miniscule and irrelevant to me. the extended performance 10w30 I believe has much more zinc than then regular 10w30. so I would go with that the next time I change my oil + filter[k&n], which will be sometime next summer [year].

 

I personally felt no need to make a change.

As the above poster i spent hours researching oil, as pathetic as it sounds.

I deduced that there is no point, with the age and mileage.

In my case, getting 2k more miles out of the oil made no sense, both Dino oil and syn, would work out to the same cost [for me].

Except with syn. i have no guarantee [little voice in the back of my head] that it will or will not have adverse affects.

Mind you i am higher mileage than you @ 109k on a 2001 car.

The car runs mint, i take care of it and stay on top of maintenance. The oil is changed religiously [as oftentimes the term it thrown around it loses its validity nowadays, but in my case it is true!]

Anyways the way i saw it was "if it ain't broke don't fix it" attitude:

1. Car was ALWAYS using Dino oil
2. No added gains/benefits
3. Potential risks [and i used this loosely]
4. No sludge issues present/running perfect
5. Oil goes in golden, and it comes out golden [a tad darker, as is expected]

That was my thought process, hopefully it offers another perspective.

I pretty much did the same thinking when deciding to change the transmission oil a month back now. I simply stuck with OEM spec, vs. M1 oil. Again purely for above points...

 

well the syn can last you 15K miles easily

okie dokie on the rest

 

Well after reading all that, I may decide to stay with convetional in my 123K mile ES. Hopefully all will be well in my 04 RX which has 80K miles.

 

For what its worth I changed over to Mobil 1 with 121K on my ES.

Car runs perfectly, doesn't burn any oil, and the oil seems to stay much cleaner and golden, if that means anything. It also adds to the peace of mind that you are putting in good quality stuff for a car you care about.

But in any situation you can't really go wrong. Nothing wrong with keeping conventional in it. And if you do put in synthetic and it leaks, just just go back to conventional.

 

How long have you been using the syn in your ES? Do you have enough miles since the change to determine if all is well?

It's kinda strange to be confused of moving from a conventional oil to a synthectic. Most would think the more expensive, better quality syn oil "must be better" right.