GA400

I wanted to share my experience with different oils on my 91 LS400 now with 207,000 miles.
First off, the car runs great. It is very smooth with lots of power, no apparent engine problems, transmission problems, fuel delivery issues, no oil leaks (more on that later), etc. I was just curious what my experience would be with different oil types. This is no scientific study and I did not have the connections to get my oil analyzed. I bought the car in May with about 196,000 miles (receipts from prior owner indicated all dino oil changes) and have had the oil changed several times since then. I had read that synthetics in higher mileage engines could sometimes make leaks apparent that were not seen before due to synthetic's smaller molecule size (or something like that ), but I wanted to try it to see what difference it would make for me. My typical driving is a 50 mile daily commute with lots of stop and go and occaisional high revving speed-ups to get out of traffic (and because I like to hear and feel that V-8 - Toyota makes great engines :-) )

First, I went with Castrol Syntec, a blend of dino and synthetic oils. Car ran same as before, no apparent increase in fuel economy or power that I could discern, no drop in engine temp. No leaks to be found on the garage floor or oily dots on my back bumper.

Second, I went with Quaker State synthetic. I was going to try Mobil 1, but there has been a lot of heated discussion on their changing base stock, and my mechanic uses Quaker State synthetic in his Ford Ranger pickup and it has over 250,000 miles with no leaks or engine problems at all. Result? very smooth engine response, seemed to be quieter, seemed to be a bit better fuel economy, fuel economy average ticked up from approx 17.5 mpg to 19 mpg. The bad news? a small oil leak came and went based on a leak on the cardboard I leave under my car in my garage - I searched with a flashlight but could not find the source of the leak, it wasn't there every day, and never was severe. Also, I had oily dots on the back bumper, possibly due to blow-by.

Third, I am now using Valvoline MaxLife, specifically designed for older engines. It has an ingredient to seal oil leaks (ester?) by swelling seals, a lubricant (PTFE, like Slick 50), and some other ingredients designed to aid an older engine. According to Valvoline, MaxLife:
Helps condition seals and prevent leaks
Helps reduce oil consumption
Helps reduce deposit formation
Helps provide easier cold starts
My impression so far (about 200 miles, a few days driving) - car feels a bit more powerful with quicker response, the oil spot on my cardboard has not returned and my rear bumper has stayed clean. No difference noted in engine temp. It seems to idle a bit quieter as well.

I will follow up when it is time to change oil again (about a month and a half based on my average miles)

I hope this is helpful to someone,

Peace,

GA400

MGS4

Quaker State also makes oil for higher mileage engine. Perhaps you could try it. Check out the link

http://www.quakerstate.com/pages/pro...hermileage.asp

GA400

MSG4,

Thanks for the tip, I hadn't seen that one around down here in GA. If I can find it, I will try the Quaker State Higher Mileage one next and post my experiences back to this thread.

Peace,

GA400

kreativ

GA400,

Excellent post, a good read.

LOTC

I just had Valvoline Synthethic 5w40 put in my LS400 and it is much smoother than before and feels more powerful, although it was running pretty strong and smooth before.

I had my tranny oil changed with Toyota ATF Type4, fuel injectors and intake valve cleaned, differential oil changed to synthetic oil, and Valvoline synthetic 5w40 and the car just feels much better all around. I only commute around 8-11 miles per day so I cant say much about gas mileage, but I will make 50 mile round trip to L.A and find out this thrusday.

GA400

E-Dogg,

I am curious how you got your fuel injectors and intake valve cleaned. Did you go to Lexus or another type of shop or did you do it yourself? Approximate price?

Thanks

GA400

GA400

Guys,

I have made a mistake. What I thought to be an oil leak caused by synthetic fluid was actually a transmission leak. I confirmed this by putting it up on the rack today and checking it out with a flashlight. This may be partially due to the synthetic fluid since I was definitely doing some high-revving and high speed runs to see if I could feel a difference due to synthetic versus dyno oil. I will get the transmission leak fixed in the near future,(it is a very slow leak) but now I have to wonder if I should go back to synthetic since my primary fear was the oil leaks. I have been happy with the MaxLife, but I understand that the synthetic yeilds better gas mileage due to lower friction and causes less wear for the same reason.

Any advice?

akmpres

For those of you who don't know me, every time i fill the tank, i run numbers, IE miles driven and galons filled, and Average MPG. I have a 99 NSX-T and a 92 SC400. My driving the lex consists of long road trips from New York City, to harrisburg PA, and sometimes down to baltimore. Ok to my point....


I have used Mobil 1, Mobil Blend, and regular mobil, and also Max Life.

Overall the milage remains the same, i get around 24.5 MPG per tank, around 386 miles per tank on average, sometimes as high as 420. I fill it right when it gets to the last line, i dont let it go below.


Mobil Blend and Mobil 1 - engine sounds louder, can hear light ticking noise during idle, and no its not the heat sheild, for every 900 hwy miles i have to add 1/2 quart.


Max Life- Gives it a solid engine sound, no ticking, good response to the petal. 1/2 quart for every 1200 miles.

I like the max life beacuse the engine sounds better during idle and also is quiter when i jump on the gas.


These tests were conducted over a 25,000 mile period.

Let me know what you guys think, excuse the poor spelling and bad grammar.

GA400

akmpres,

Thanks for posting your experiences. How many miles do you have on your SC400?
I think I may be sticking with the MaxLife oil as well. I have been very happy with it and my car definitely has more pick up off the line. I have unintentionally chirped my tires when leaving work a few times recently. Car never did that until a couple of weeks ago. The only difference is the oil.

Thanks

GA400

akmpres

GA400,


I got 115K miles on mine, got it some time back from an old guy who took great care of it. i have the mobil blend in it right now, im changing back to the max life and sticking with it.

GA400

Cool!

SCV8

My first oil experience with this car came on the way home;while driving at over 100 all day,the car will lose some oil I found.
So,no problem,this is why these cars last so long;no ring pressure on chrome rings,my Germancars have had chrome rings, just need to use a little thicker oil for performance use.
I found 10w40 to give a nice boost,might try 20/50 Kendall later,which is THE quietest,stickiest oil I've ever used,can make a sloppy old race toleranced motor sound tight and smooth.

Another product that has actually added a few horsepower from reducing boundary layer(metal-to-metal)friction,is PowerUp.

Lexmexico

I live in Mexico with my RX, and we have most of the synthetic oils available, including Castrol, Mobil and Quaker State.

I have used varying weights of Mobil 1, 5W-30, 10W-30 and now 15W-50, both with and without supersyn. I switched to the 15W-50 after I notice poor performance at the high altitude, Mexico City. After changing to 15W-50 supersyn for the past 2,000 miles, the car feels more fluid, and I notice better performance on MPG and takeoff speed.

One of the local service places in my neighborhood uses Quaker State synthetic, and most customers have notice improved performance, but the mechanic stopped recommending it for SUV/Trucks, as it does not seem to have the same effect.