havic

Does high mileage oil make a difference? I have 87,000 miles on my 98 and I've seen some high mileage oil on the market that says for vehicles over 75,000 miles. Would it be beneficial to use that oil? And once you use that oil, is it one of those things that you have to continue using (ex. would it hurt the engine to switch back to regular dino oil)? Thanks.

Highland Runner

75,000 is high for American made vehicles, but not a Toyota. Every Toyota I've bought has had over 100,000 miles. 87,000 is nothing. Check out
http://theoildrop.server101.com/cgi/ultimatebb.cgi?
for info on oil. I think the high mileage stuff has conditioners to make seals soft again. You can change oils any time you want including going back and forth from dino/synthetic.

4RunnerFever

I'd suggest synthetic. Either Mobil 1 or Amsoil. This should prolong the life of your motor indefinitely.

Highland Runner - you should get a website Nice Truck!

Highland Runner

Thanks 4RunnerFever. And I second the two oils you mentioned. I started running M1 about 15,000 miles ago, because my mileage is getting high. Runs great.
4RunnerFever- your Runner is very nice also. I'm always impressed by the number of well built trucks/SUV's in Boone/Banner Elk area. Must be a necessity with winter and road conditions.

mike_d

no, don't use it. it's not a good idea. i'm at work now, so i don't want to take the time to search in the newsgroups for the posts, but basically the high-milage oil has some stuff in it that helps the seals swell to stop leaks and some other stuff. basically it's good for short term fixes on old engines. but it is no good for the long term. i remember briggs and stratton did some in house tests and found that initially the high-milage oils, and oils with additives like teflon did very well, but in the long term they found significant scoring and wear on the pistons and bearings.

i'm a believer in synthetic oil, particularly mobil 1, but i bet any good synthetic will do. as a chemist, i've read a bunch about synthetics and they are significantly better than mineral oils. and for me cost isn't an issue because i put the new oil in my new car and use the oil from my new car in my old trucks, and even after 6000+ miles and 2 vehicles the oil comes out mostly clear.

jimbo74

i dont know about the testing of damage... however, all the high mileage oils are are oil with more detergents/cleaners for older engines.....

the shouldnt increase/reduce wear, however, they will help keep rubber seals softer allowing less oil leak if you already have one....

if you change the oil at regular intervals, you dont need high mileage oils..... either dino or syn

bike4miles

I used castrol high milage in my 4runner (165,000 miles) and it actually increased my oil presure! I'm not kiding. Seriously. It cost like $5 a quart but I plan on using it again next time.

mike_d

actually, the rasising of the oil pressure might not be a good thing. from what i remember about the briggs and stratton test was that extra stuff in the oil will block the smaller channels that the oil goes into and cause extra wear because of oil starvation. that may be what's happening in your truck, if the pressure is high, that could be because the oil isn't getting through to all the places it should. i'll see if i can find that test i'm talking about so that people don't need to take my word for it.

mike_d

here's what i was able to find.

http://www.vtr.org/maintain/oil-additives.html

i'm sorry, i couldn't find the other document i was thinking of, but this one is not bad.

radrex

This may have been true about American Vehicles in the 80's and is still true about some. But I'd suggest you evaluate the Wards Top 10 Engine list and JD Powers reliability ratings.

Basically, you get what you pay for.

jethro

Welcome to Yotatech. Looks like we were a little more help.
http://www.automotiveforums.com/vbul...d.php?t=251467

Highland Runner

Cut and pasted directly from the JD Power site.

Listed as below average in long-term dependability are, in alphabetical order: Chevrolet, Chrysler, Dodge, Eagle, GMC, Hyundai, Isuzu, Jeep, Kia, Land Rover, Mazda, Mitsubishi, Plymouth, Pontiac, Suzuki, Volvo and Volkswagen. Power does not publicly release the below-average rankings.

But Power does name the top vehicles in each category, and here Toyota holds an impressive six first-place spots with its Tacoma, T100, 4Runner and Supra models. Lexus garners two spots with its LS 400 and LX 450, and Honda holds two top spots with its CR-V and Civic.

Source: J.D. Power and Associates 2001 Vehicle Dependability Study

Looks like it's still true.