Synthetic oil.. opinions?

[CurleyMan]

I am running synthetic oil in both of my foreign vehicles. The Nissan has synthetic in the diff's. The Bimmer Has it in the motor and will soon have it in the rear diff. I don't see any reason to put it in the Jeep cause i don't think it will last more then 10 years. I am thinking of putting the sythetic in my Nissan motor, t-case, and tranny. I was wondering what everyone here thinks of synthetic oils. Is anyone else using them or thinking about it in the future?

[Allen Cox]

I like them. I really do see an improvement over dino oils.

[Bill Potter]

I used to use them...but I decided that now days most motors outlast the rest of the car anyway.

I also can't bring myself to go the 15,000 - 20,000 miles between oil changes synthetic oils allow.

[ChefTyler]

15,000? I've heard 5,000-8,000 but not 15 - 20...but I could be misinformed :D

[CurleyMan]

I'll be swapping it out at 5,000... All of my vehicles have over 200,000 so i can't mess around with any sludge or poor viscosity issues..

[Bill Potter]

I think regular moble 1 used to advertise 18,000 or something like that. Now they advertise 15,000 on there extended life oil.

http://www.mobiloil.com/USA-English/MotorOil/Oils/Oils.aspx

If it's on the web it must be true....(just kidding)

http://neptune.spacebears.com/cars/stories/interval.html

http://www.nordicgroup.us/oil.htm

[theking]

Definitely in the tranny. I noticed when i drained my tranny it can out like a foam froth. This was generic napa Gl-4. Redline mt90 is way easier to shift now.

[Packman5280]

i think the benefit on an older motor is questionable, but deffinately in the trans and diffs. i used regular honda MTF in my civic cuz all the ricer guys said it was better than a synchetic though. i would really like to get some MT90 in my pathfinder trans and case.

[Bill Potter]

If you change it every 5000 miles I would just use reguler oil. The 3 month 3000 mile oil change is mostly a grease monkey/jiffy lube sales ploy.

I just read the owners manual and follow that. My last three cars have all gone well past 200,000 miles changing the oil somewhere between 4,000-6,000 miles. I got rid of them because of a mass of other problems, never oil related.

[Allen Cox]

I do the same thing, running about 4500 miles on a change. Once I get my Frontier around 30k miles, I'll switch it over to Mobil1 or Royal Purple. We sell the purple, so I can get a deal.

I'll be switching over to the synthetic in my transmission once I get the dough to do so. The t-case will probably be drained here this summer (about 1k on it since the last change) due to an experimental whatnot (if money and the wife permits :D ). The diffs will be synthetic, once I actually build 'em!

[CurleyMan]

Hey allen how long should I run fossil oil in the new t-case. I want to break those calmini gears in but switch over to synthetic quickly afterwords. I was thinking 500 miles would be a good break in limit, Is this too soon?:confused:

[DamnHippie]

I'm now synthetic in every fluid except the power steering, and I'm gonna switch that over to synthetic ATF in the next week or two. The automatic transmission is the expensive one to do, but since I had the engine out it was easy to completely drain the tranny including the torque converter, so that I was able to get 9 quarts of synth in there without needing to waste a bunch of extra for a power flush.

For the engine I use the Mobil-1 extended 15,000 mile kind, and change it once a year (which is usually way less than 15kmiles). I still change the filter every 3-4k and top off with a bit of fresh synth juice to replenish the buffers and detergents such that tend to degrade with heat over time.

[Allen Cox]

Ben, I'd probably run it in 4 low for a while before changing it out. Remember, those gears aren't getting used in 2 hi, only low. So maybe after GONE, then I'd switch to syn in it.

[CurleyMan]

Thanks for putting my t-case gears in Allen it's good to know they where done right.

[Allen Cox]

Any time Ben! Glad to know they'll be used, and not going into a mall crawler so they can put a sticker on.

[DamnHippie]

I don't understand why people think you need to use dino fluids to break something in. Mark my words, within 5 years just about every new car down to the very cheapest is gonna come from the factory with synth fluids in it bumper to bumper.

[CurleyMan]

Yes I fully agree with you. My parents cars came with synthetic from the factory and many semi trucks are already doing this. Semi engines cost more then most automobiles so they usually don't take risks. However i want to break my gears in the old school way. At this point with my SYE, crawlers, and labor they have easily cost me 2,000 bucks. So I would rather heat them up with dyno oil then synthetic. I have considered the alternative and I will not take the risk. I need to know that the metal has reached the proper temp and bonded with the proper oil.