BostonBill

I have a 94 LS 400 and with 97k and does not leak a drop of oil. I've had this car for 6 months and got it from someone who had it Lexus serviced. I have a good mechanic that will work on this car. He changes the oil, etc.. and lets me bring my own filters and oil and other parts.
I see a lot of people recommend Mobile One and good filters. I have bought Denso filters and was all set to buy the Mobil One when I read in one of the threads here that the new synthetic oil could cause the seals to leak. I don't understand this, but do not want to cause a problem when I don't have one. I just want to do the best for my Lexus. I love this car already.
Any thoughts. I have an oil change scheduled for this week.

Thanks

PureDrifter

iTrader: (10)

i switched my '95 LS400 onto mobil1 synthetic 5w-30 (i think thats the weight) and i havent had a single problem.

Pagong

No problems for me...1990 LS switched to synthetic a couple of oil changes ago!

clean95

they say it causes leaks because the oil is much finer than regular oil has more stuff ur car doesnt need so some people who have old seals teh new synthetic oils wont plug up the seals like reg oil

RA40

iTrader: (6)

The oil in itself will not cause the seals to leak. The nature of the synthetic is such that it's viscious nature allows it to penetrate/migrate out worn seals. I experienced this on one car and try as I might, it was a losing battle. After 2 synthetic changes even with a 10-30, I went back to a dino oil and the oil migration was gone.

My '80 Celica has synthetic in it and other than a small drip from the oil pan plug, that engine is tight. YMMV, so put it in and check. If it begins to migrate out or leak agressively (as in more than what you think is tolerable) switch it back.

PureDrifter

iTrader: (10)

yeah, after u switch it, id watch the motor's oil consumption VERY closely to make sure it isnt leaking/burning on you.

gtfour43

WTF????? Give real facts

gtfour43

How does oil make it run rich?

Lextreme90

Just bought a 1990 LS400 with 99k miles on it. I know for the couple weeks I owned the car there was no oil leaking at all. In fact I checked out the underside and it was dry. I just changed the oil to Mobile 1 synthetic and after a few days I have noticed a couple drops of oil on the ground. I looked and it is dripping from the pan somewhere. Not sure if it is just the plug yet. Will check it out more this afternoon. Could just be the plug seal.

denverdog

i got my ls at 88k and switched immediately to mobil one 5/30. at nearly 200k imoved to 10/30.
no problems. what this thread is referring to is not that synthetics have damaging chemicals. it is just that synthetics are less viscous, and flow more freely, especially in the cold. i would never switch back to dino oil.

gtfour43

Yup in fact I have seen what Mobil 1 can do for an engine. A customer of ours had used Mobil 1 10w-30 in his Previa for 10 years. After 155k miles we took his valve cover off and looked inside to find the motor still looked brand new. It had no varnish or gunk buildup like other engines we had taken apart. It still had a nice gold color to all the internals. He changed his oil religiously every 5k miles . Since then Mobil 1 has been the only oil for me.

steveski

I have a 95 LS400 with 153,000 miles. I have used M1 full synthetic for 9 years - no issues. One of the best oils out there.

BostonBill

Thanks for all the replies. I have an oil change tomorrow and it will be Mobile One and a new Denso Oil Filter. No more cheap filters.

Thanks Again

jz4203

Good luck with your switch to Mobil 1. When I bought my 96 LS400 at 78k, I switched to Mobil 1 with no issues. That car 6 years later is at 165k miles. Did the same when I bought a 98 GS400 with 156k miles. Three years later at 205k, no oil leaks with Mobil 1, though I have switched from 5W/30 to 10W/30 when I noticed I was consuming a quart of oil over 5k miles.

Don't know anything about the Desno filter, but I've been extremely pleased with the Mobi 1 filter for many years.

lorenzo816

Whats the part # for a denso filter on a 1st gen lex LS400