Mobil 1 Synthetic

[SRK]

I have used Mobil 5W-30 synthetic for years in my other cars. Tonight I switched my (new to me) 92 LS400 to it, and as I thought, it made a quiet engine even quieter.

The car has only 116k kilometers on it, about 65k miles, so I think it is worth converting to synthetic.

[ToddLS400]

Miles are low. Kind of fishy...What's the story on your car? What color? How much did you get her for?

[SRK]

That's why I bought it - one owner, Vancouver car, complete records showing all mileage accumulations at each service. Its history is fully substantiated by the two Lexus dealers it was serviced at. In Canada we tend to drive fewer miles per year I think.

It is gray blue metallic, with the blue interior. I didn't want a white one, but would have bought a black one. My 94 Z28 is black - excellent colour.

[lexusman91ls400]

Not to sound smart or anything but did you have the timing belt replaced and the valves adjusted at 60,000 miles? If not then thats your problem.

[UCF3]

I don't use anything other than Mobil 1 Synthetic. I know my car will continue to purr like a kitten for years to come. :)

[SRK]

Timing belt service was done at the seven year interval, rather than the 96k kilometer interval, so all is well.

[UCF3]

ANything else wrong with the car, that you can think of? <_<

[SRK]

I'm not sure where this thread is going anymore.

In any event, I did have to replace the left inner tie rod, the left outer tie rod, and have a four wheel alignment performed.

It needed new tires so I got a set of Bridgestone RE930i's. They seem to work well.

Tach needle is half dead.

Rear subwoofer doesn't work at all.

;)

[UCF3]

I believe someone else wanted to know if the timing belt might be an issue, and you mentioned it was replaced. I'm kind of curious why changing the oil caused your car to sound better. I've never heard that just changing the oil caused a car to quiet down. It sounds a little fishy to me. It's raising some red flags that there maybe something else that might cause the engine to quiet down. If everything is okay, just ignor us.

[SRK]

I understand now - thanks for replying.

I mentioned the quiet thing about synthetic oil as I have observed this in every other car I have owned and used Mobil 1 in - the higher film strength of synthetic tends to reduce valve train noise in particular. Given how quiet these Lexus engines are to begin with, I wasn't expecting to notice any change, but it is there, IMHO, as slight as it may be.

Todd's "fishy" comment I took to refer to the low mileage on the car - which it certainly has, but it is documented completely, which is why I bought it.

[hammo400]

Hey SRK !

Well done on the Great buy ! I bought a 1991 LS 400 last October with 96 K miles when purchased - all records going back to mile 8.

Interesting about the Mobil 1 . I had began using Quaker State 5W 30 Full synthetic at my first oil change. I change every 3K like clockwork. I have heard of Mobil 1 as a really good oil.

With age and use, any engine - even the Lexus - will need some extra TLC. As I now have 107 K on the clock, I was thinking of switching to Mobil 1, but the 10W-40 synthetic blend for higher mileage engines (>75K).

Is there any harm in switching from a Full synthetic of one brand to a different weight synthetic blend from another brand ????

I notice that there is a faint, yet noticeable rythmic "ticking" when my engine is running. I think this may have to do with the lifters and wonder if there is anything to do to quiet / eliminate this noise without a major engine overhaul ??? The timing belt was changed at 60K by the previous owner (documented), and I'll replace it again at 115K. I've tried Prolong - which helped with mileage / horsepower - but not with lifter noise.

Any suggestions anyone ????

[SRK]

First of all I would avoid any additives at all. No independant testing has shown any improvement from any of them, and many degrade the original oil.

I am sure the Quaker State is good stuff, and all API rated oils will be compatible with each other, so there will be no problem switching over.

I believe the ticking sound you hear is probably the injectors, which are about the loudest thing on these engines. Most modern engines make that noise at least, in addition to others. I am also sure that no overhaul is indicated - everything I have learned about these engines points to very long, trouble-free services lives.

[hammo400]

SRK,

Thanks for that bit of info. I plan on switching oil and filter to Mobil 1 at next change.

I'm curious as to why you put the 5W-30 - which is for newer engines - in your 92, and not an oil specially formulated for higher mileage engines, like the 10W-40 blend ??

I don't recall this faint rhythmic 'ticking' from my previous '91 LS 400, but maybe I wasn't paying that close attention. This noise was brought to my attention by someone else, and then - of course - it's all I hear!

[SRK]

I use 5W-30 as it is the one recommended by Lexus. My 94 Camaro Z28 uses it too. And I have converted many customer cars to it. Works just fine. 10W-40 is considered a rather obsolete viscosity these days, and in any event I don't think either type of V-8 needs it. The trend is to thinner oils - both Honda and Ford now specify 5W-20. In northern Canada, 0W-30 is common in the winter.

With the 5W-30 I notice that the cold cranking speed of the engine is about the same, winter or summer. That means the oil isn't dragging the engine down, and it gets to the lube points and builds oil pressure much faster than a thick oil.

Now that many manufacturers specify synthetic as a factory fill, I think that we will see more and more use of synthetics, and eventually they will replace conventional oils altogether.

I first used Mobil 5W-20 when it came out in 1980. Really thin, but it worked well.

[m2pc]

I am looking into Mobil1 or Amsoil synthetic. found a distributor who wll sell it comparable to Mobil1. Question is, since the synthetics cost 3-4 times more /qt, how often do you change out the oil? I was thinking 5-7k miles.

[SRK]

Most synthetic manufacturers do not promote their oils as extending drain intervals. I know that Amsoil does. Mobil does not.

I use Mobil synthetic, and have never considered any other brand. For non-synthetic types I use Esso (Exxon) oils here in Canada. Mobil 1 5W-30 is about $6.50 a litre on sale, so about $4.50 US. That's about 2-3 times the price of a conventional, and well worth it even at the same drain interval. I would not exceed 5k miles as a an interval.

Most people change the oil too frequently when a car is new, and then extend the intervals as the engine ages. It should be the other way around. As the engine ages, blow-by increases, and the rate of deposit goes up. Therefore, the oil should be changed more frequently as the engine gets older.

[VBdenny]

I have used full synthetic oil in all my vehicles for many years. I have used Mobil 1 which is good. You can buy it by the case at Costco for around 35 bucks (6 qts.). I use Valoline full synthetic. The original owner of my 400 use Amsoil since it was new. I don't really think it makes much difference what brand of oil is used, rather that it is syntheic and changed freequently. I use a 3 month, or 3000 miles basis. I also use a fram XG oil filter which sell for $10. Synthetic oil is particularily useful is extreme heat and cold conditions as it stays at a consistant viscosity at all times. As mentioned previously I would not use 10-40W as is not recommended by Lexus. You will also lose what little gas milage you get. Enjoy the 92 it sounds like a sweet unit.

[jzz30]

i was told that synthetic lubrication is so good that it isnt really good to use it in the first filling from the factory. Is this true?, that the engine will take longer to break in or has modern machining proceses gone up in tolerence so much that there is no need for such a break in process so that auto manufacturers can go ahead and use synthetic as a first filling?

[SRK]

There are many myths about synthetics that are dying hard. One of them is that it is not suitable for engine break-in. In the old days that was true, but as you correctly suspect, modern engine machining techniques allow synthetics to be used from day one without excess oil consumption. When you consider how critical oil control is to modern emission systems (O2 sensors, catalytic converters) that is really saying something. All GM Corvettes, all Porsches, all high performance Jaguars, all AMG Mercedes come with Mobil 1 as a factory fill, and BMW M-cars come with a German made synthetic from the factory. There are probably other cars now using synthetics from the factory, and my prediction is there will come a time when all cars will.

[mig25]

The ticking noise is eliminated by a valve adjustment job, wich is not going to cause any harm if it is not done. It most likely comes from cylinder number 5 and 7. I have the same noise in my LS400 1990 with 130.000 Miles. The oil information, viscosity all depends on the climate, let's say for example if you live in Phoenix AZ, you don't want to run the 5W30,thru the summer, but it would be a good pick if you lived in Barrow, AK.

Rmember, Lexus makes the engine not the oil. Always check the oil specs by the manufacturer. I am running 10W30 here in the midwest year around.

[VMF]

whats the difference between sinthetic and semi sinthetic? also which oil would u recommend for use in hot and humid new york climate?

[jzz30]

just stick in a fully synthetic oil its the best

[darcmater]

then theres always Royal Purple 10-30...or even 20-50.