Best oil for 1999 Lexus GS300? Need opinions...

[joshua777]

I know this topic has been beaten over the head 1,000 times and trust me I've read every forum, many being from yeeeaaarrrrs ago. I currently have 196,XXX miles on my 1999 GS300 and have used Mobil 1 High Mileage Full Synthetic 5W-30 for about 2 years now. It's great, but I still burn through about 1 quart every 5,000 miles. I've been thinking about switching over to 10W-30 in a few months, since I live in San Diego, and summer weather will be here before I know it. When I make the switch, I was wondering opinions on <span style="font-weight: bold">Pennzoil Platinum High Mileage 10W-30</span> and <span style="font-weight: bold">Mobil 1 10W-30 High Mileage Full Synthetic</span>. I want to get other's opinions, <span style="text-decoration: underline">say money is no object when choosing between the two</span>, which one would you guys recommend? I've recently read claims that Pennzoil is better and keeps the engine cleaner, and just helps maintain better than Mobil 1, but it's impossible to get non-sponsored opinions in 2018.

 

[raytseng]

i have a 1998 gs300. it did well on Pp and pup 5w30 normal. One oci i used m1 and had increased consumption. However this engine still needed a .5qt topoff say halfway through my 7500oci. At the end of the oci the stick was in thr middle and ready to change. I would suggest you try a different brand and stick with spec. Obviously M1 isnt making you happy. I don't know why you are staying loyal to it and going so far as to go offspec before trying a non m1. If it turns out the same on PP at least you know.

 

[Anthony]

I would keep running M1 HM and move to their 10w40 grade.

 

[raytseng]

As far as the engine and performance and perceived cleanliness, I've found the engine to run slightly better if the fuel has some ucl. Also the rest of your maintenance is going to play a larger role over your oil. As far as fuel, in particular shell vpower was smoother than chevron premium. I think the shell addpack has more ucl. Or if you want to roll your own, using maintenance level dose of redline si1 with any station is best at providing the increased smoothness (and injector cleaning) Note I've driven and maintained my gs for 20years so buttdyno is finely calibrated so take my experience and expertise into account. Of course its your car so do whatever you want with it.

 

[CT8]

Oil is oil .Try different brands 1qt in 5,000 miles isn't bad and what is the causeof the oil consumption if not the oil brand or type.

 

[Graham Piccinini]

I had that engine in my IS300 and it definitely ran the happiest on 0w40 oils. Mobil1 0w40, if you wanna stay with the same brand, or Pennzoil Euro 0w40 at Walmart are good choices. Castrol 0w40 made the engine a bit more sluggish. Just my 2 cents from personal experience with that engine. I even tried 0w20 in it, did not like it though. 0w30, 5w30, and 0w40 are your best bets. Some 5w40s made it too sluggish, just like Castrol 0w40.

 

[LeakySeals]

1 quart is not that bad considering the engine and year. Yes you may consume more M1 HM, but the reason is better flow. Want less consumption? Use a thicker poor flowing oil. You need to know why its consuming. If its rings or blocked oil control holes, HM oil won't help you. If its rubber valve seals (blue smoke at startup) then yes, it will help by plumping them up. When is the last time you replaced the PCV valve? I know that era had issues with the PCV system.

 

[Leo99]

Originally Posted By: CT8

Oil is oil .Try different brands 1qt in 5,000 miles isn't bad and what is the causeof the oil consumption if not the oil brand or type.

Exactly. Try different oils and the best one might lessen the oil consumption to 25 oz per month instead of 32 oz. My Rav4 uses a bit of oil. Maybe 1.5 qts every 5000 miles. I used whatever HM oil I can get for cheap. Right now it has Castrol green bottle in it. I find that switching oils works best for it. Next change will be ST HM and then maybe Pennzoil HM and then Valvoline Max.

 

[fdcg27]

A car of nearly twenty years with 200K using a quart in 5K isn't consumption at all. I wouldn't even try to chase this down with different oil brands. Won't likely matter. All you can do is ensure that the PCV system is flowing properly and that the PCV valve itself is working. Other than that, motor on in this fine old-school Toyota design and just dump in a quart every 5K. The old GS and LS cars are very nice to drive and seem to hold up very well.

 

[JC1]

Originally Posted By: joshua777

I know this topic has been beaten over the head 1,000 times and trust me I've read every forum, many being from yeeeaaarrrrs ago. I currently have 196,XXX miles on my 1999 GS300 and have used Mobil 1 High Mileage Full Synthetic 5W-30 for about 2 years now. It's great, but I still burn through about 1 quart every 5,000 miles. I've been thinking about switching over to 10W-30 in a few months, since I live in San Diego, and summer weather will be here before I know it. When I make the switch, I was wondering opinions on Pennzoil Platinum High Mileage 10W-30 and Mobil 1 10W-30 High Mileage Full Synthetic. I want to get other's opinions, say money is no object when choosing between the two, which one would you guys recommend? I've recently read claims that Pennzoil is better and keeps the engine cleaner, and just helps maintain better than Mobil 1, but it's impossible to get non-sponsored opinions in 2018.

Try some Liqui Moly Motor oil saver and keep using the M1 5w-30 HM. https://products.liqui-moly.com/motor-oil-saver-3.html

 

[maverickfhs]

Originally Posted By: fdcg27

A car of nearly twenty years with 200K using a quart in 5K isn't consumption at all. I wouldn't even try to chase this down with different oil brands. Won't likely matter. All you can do is ensure that the PCV system is flowing properly and that the PCV valve itself is working. Other than that, motor on in this fine old-school Toyota design and just dump in a quart every 5K. The old GS and LS cars are very nice to drive and seem to hold up very well.

+1 Million, 1 quart after 5K is nothing. Cheap insurance and these cars are built like TANKS

 

[Gebo]

I'd use the Pennzoil in the 5w30 weight just for fun. It may not use as much oil or it may use more. You'll never know until you give it a try.

 

[joshua777]

I've used Shell VPower, exclusively, for about 5 years now. I will never use any other gas, incredible stuff.

 

[joshua777]

Originally Posted By: fdcg27

A car of nearly twenty years with 200K using a quart in 5K isn't consumption at all. I wouldn't even try to chase this down with different oil brands. Won't likely matter. All you can do is ensure that the PCV system is flowing properly and that the PCV valve itself is working. Other than that, motor on in this fine old-school Toyota design and just dump in a quart every 5K. The old GS and LS cars are very nice to drive and seem to hold up very well.

Yeah that's basically how I feel, 1 quart every 5,000 isn't that bad. There's literally nothing wrong with the car. This is the biggest, and only, "problem."

 

[spiderbypass]

Mobil 1 0w40 fs is hard to beat. Maybe 5w50 Mobil 1 fs ior 15w50 in Warmer temps.