Switching To Mobil 1 Synthetic ?

[George Z.]

I am new to the forum and I just purchased a 1997 Lexus LS400 with 147k miles. The car is in excellent shape and runs like a champ. I've already put 2500 miles on the car with no problems and I'm also getting excellent gas mileage.

I have traditionally used Castrol GTX 10-30 (conventional) oil in all of my cars - both domestic and imports. My questions is as follows: would you guys recommend me switching to Mobil 1 (full synthetic) motor oil & going 5000 miles between oil changes or sticking with the conventional Castrol 10w-30 and changing it every 3000 miles?

When a vehicle has this many miles, and assuming it's always had conventional oil, is it harmful to change it to full synthetic? Are there any possible ramifications or repercussions in doing so?

I am very pleased with this LS400 as it's my first Lexus to ever own and drive. It's truly a pleasure to drive and travel in. I will soon be in the market for one of the newer '07 LS460 models.

Any help will be greatly appreciated.

Thanks in advance for all of your help.

PS - I live in the Houston, TX area where our summers are brutal with lots of heat and high temperatures.

Thanks again.

[PureDrifter]

I am new to the forum and I just purchased a 1997 Lexus LS400 with 147k miles. The car is in excellent shape and runs like a champ. I've already put 2500 miles on the car with no problems and I'm also getting excellent gas mileage.

I have traditionally used Castrol GTX 10-30 (conventional) oil in all of my cars - both domestic and imports. My questions is as follows: would you guys recommend me switching to Mobil 1 (full synthetic) motor oil & going 5000 miles between oil changes or sticking with the conventional Castrol 10w-30 and changing it every 3000 miles?

When a vehicle has this many miles, and assuming it's always had conventional oil, is it harmful to change it to full synthetic? Are there any possible ramifications or repercussions in doing so?

I am very pleased with this LS400 as it's my first Lexus to ever own and drive. It's truly a pleasure to drive and travel in. I will soon be in the market for one of the newer '07 LS460 models.

Any help will be greatly appreciated.

Thanks in advance for all of your help.

PS - I live in the Houston, TX area where our summers are brutal with lots of heat and high temperatures.

Thanks again.

the 3000mi oil change is a myth.

i run ~8k mi between changes, bosch filters and Mobil1 full syn. 5w-30 (switching to 10w-30 due to the weather in my region).

[George Z.]

I am new to the forum and I just purchased a 1997 Lexus LS400 with 147k miles. The car is in excellent shape and runs like a champ. I've already put 2500 miles on the car with no problems and I'm also getting excellent gas mileage.

I have traditionally used Castrol GTX 10-30 (conventional) oil in all of my cars - both domestic and imports. My questions is as follows: would you guys recommend me switching to Mobil 1 (full synthetic) motor oil & going 5000 miles between oil changes or sticking with the conventional Castrol 10w-30 and changing it every 3000 miles?

When a vehicle has this many miles, and assuming it's always had conventional oil, is it harmful to change it to full synthetic? Are there any possible ramifications or repercussions in doing so?

I am very pleased with this LS400 as it's my first Lexus to ever own and drive. It's truly a pleasure to drive and travel in. I will soon be in the market for one of the newer '07 LS460 models.

Any help will be greatly appreciated.

Thanks in advance for all of your help.

PS - I live in the Houston, TX area where our summers are brutal with lots of heat and high temperatures.

Thanks again.

the 3000mi oil change is a myth.

i run ~8k mi between changes, bosch filters and Mobil1 full syn. 5w-30 (switching to 10w-30 due to the weather in my region).

I guess my question is more regarding whether starting to use Mobil 1 synthetic oil in my '97 LS400 is a good idea if the car has never been used to synthetic oil and it's already got 147k on the clock?

[PureDrifter]

I am new to the forum and I just purchased a 1997 Lexus LS400 with 147k miles. The car is in excellent shape and runs like a champ. I've already put 2500 miles on the car with no problems and I'm also getting excellent gas mileage.

I have traditionally used Castrol GTX 10-30 (conventional) oil in all of my cars - both domestic and imports. My questions is as follows: would you guys recommend me switching to Mobil 1 (full synthetic) motor oil & going 5000 miles between oil changes or sticking with the conventional Castrol 10w-30 and changing it every 3000 miles?

When a vehicle has this many miles, and assuming it's always had conventional oil, is it harmful to change it to full synthetic? Are there any possible ramifications or repercussions in doing so?

I am very pleased with this LS400 as it's my first Lexus to ever own and drive. It's truly a pleasure to drive and travel in. I will soon be in the market for one of the newer '07 LS460 models.

Any help will be greatly appreciated.

Thanks in advance for all of your help.

PS - I live in the Houston, TX area where our summers are brutal with lots of heat and high temperatures.

Thanks again.

the 3000mi oil change is a myth.

i run ~8k mi between changes, bosch filters and Mobil1 full syn. 5w-30 (switching to 10w-30 due to the weather in my region).

I guess my question is more regarding whether starting to use Mobil 1 synthetic oil in my '97 LS400 is a good idea if the car has never been used to synthetic oil and it's already got 147k on the clock?

as i posted on the other forum, you'll be fine :P

[oldskewel]

I guess my question is more regarding whether starting to use Mobil 1 synthetic oil in my '97 LS400 is a good idea if the car has never been used to synthetic oil and it's already got 147k on the clock?

I started using synthetic 5W30 in my 91 LS400 after ~160k miles of non-synthetic (what the previous owner used). No problems after about 1.5 years and 5k miles. Is there a reason you go with the 10W30 instead of the 5W30?

[PureDrifter]

I guess my question is more regarding whether starting to use Mobil 1 synthetic oil in my '97 LS400 is a good idea if the car has never been used to synthetic oil and it's already got 147k on the clock?

I started using synthetic 5W30 in my 91 LS400 after ~160k miles of non-synthetic (what the previous owner used). No problems after about 1.5 years and 5k miles. Is there a reason you go with the 10W30 instead of the 5W30?

it gets stupidly hot here in the summer and i don't need the cold temp properties of 5w-30 since i live in a rather warm part of southern california?

[rickatups]

Hi George Z ... welcome! Well ... I thought I would throw in my 2 cents worth of comment, if I may ..... I am a rather fastidious [automotive] maintenance nut as any of my neighbors could tell you ..... on just about any Saturday I am always out washing, waxing, detailing, and maintaining my cars in one way or another it seems ..... they all think I am kinda crazy ..... maybe they are right? (^-^)

my first LS400 was a 95 with 101,000 miles on it ..... I switched it over to Mobile 1 about a year ago (138,000 miles now) ..... and all is well. I change the oil when I do not like the look of it .... kind of a money-no-object approach on my part, and rather extravagant for sure ..... but I figure this Lexus motor is so great, .... well ... why not, you know?

Anyways ...... my most recent discovery is Royal Purple full synthetic oil ..... George ... you gotta go to their web site and see the videos they have there .... pretty interesting! I have not yet used any Royal Purple, but I am planing on switching my LS400 over to it the next time the oil is ready to be done ..... You can also find a very interesting test on YouTube ... all you have to do is type the words Royal Purple in the search field there .... pick the first video that comes up ... you will see a lab technician doing a test with some type of device made for this purpose .... I thought it was quite fascinating to see ..... I think you would find it interesting

Well .... hope this offers some food for thought ..... !

I really like my 95 LS ..... but I would really like to upgrade some day into a newer model .... I am always looking .... kinda like the 2004 LS these days ....

again .. welocome to the club here .... it is a great place to be if you own a Lexus

[AZ Mike]

George,

There are no magical mysterious differences between conventional and synthetic oils; synthetic flows better and lasts longer before breaking down.

The only reason to be concerned about switching is if you have any current oil leaks. If conventional oil finds its way out of your engine, you can be certain that synthetic will, and at a faster rate. This is for two reasons; higher lubricity allows it to flow better into small places, and it tends to clean better than conventional, so any sludge deposits keeping a seal closed or from leaking faster may be cleaned up allowing for even more of a leak.

If the car's seals are good, and the car has had routine oil changes throughout its life, there is no reason to be concerned about switching to synthetic.