Synthetic Oil in Cruisers? (1 Viewer)

[Buck]

Just finished overhauling the 2F, transmission and transfer case on my '82 FJ40.  I've always used plain 10W40 in the engine and 80W90 in the gear boxes since the truck was new.  After the engine breaks in, I'm considering switching to synthetic oils.

There's a lot of information available on the web, but it's difficult to sort out truth from marketing hype in this area.  Does anyone here have experience running synthetic oil in the 2F?  Is any benefit worth the additional cost?  Anyone have problems with the synthetics in our older-technology engines?  What weight oil do you use?

I have to say that my engine & gearbox internals still looked pretty good after running 20+ years on plain petroleum based oil, so I hesitate to change what's working without good expectation of improvement.

Buck

 

[3_puppies]

I ran Mobil 1 10-30w in my 2F for over 100,000 miles before I sold it. Never had any problems, it really helped on those cold mornings -25F, before I put in my block heater. I also ran Mobil 1 75-90w in gearboxes and axles, no problems there either. On those cold mornings, I could let the clutch out without stalling the engine.

 

[residualboulders]

I'm definately no authority on this subject, but I have read reports in the past (one on msn.com's auto section though I couldn't tell you how to find it). From what I've read the synthetics and premium fuels are not necessary unless your vehicle is designed for their use. It even stated that the frequency of recommended oil changes is more often than necessary. Just food for thought.

 

[Gumby]

I have always been of the opinion that dino was fine. The additives in syths wear out just as fast as dino and the oil gets dirty at the same rate, so you still need to change it on the same intervals.

Having said that, after 100k my 80 gets Mobil 1, just because it makes me feel better. I changed my trans fluid this week and put in blended ATF. I couldn't justify $6 over $2 a quart for full synth, but the blended was the same price.

I figure putting in synth oil is like buying flight insurance. If it makes you feel better, then do it, but I don't know if there are any benifits.

 

[Trevor]

The way I look at it, full synthetic oils like Mobil1 cost almost three times what dino-based oils cost. If they can make my engine run three times longer, I'll pay for it. I honestly can't see a 2F running for 600,000-900,000 miles between rebuilds, even if synthetic oil is used. I would rather take the money I saved by using regular oil and spend it on a rebuild every 200k to 300k miles.

 

[Pete112]

I'm surprised everyone is anti-synthetic sorta-speak. I've read a lot of research on synthetic vs conventional throughout the years and synthetics always win by a pretty large margin. I can't refer you to an exact source because I've read it in magazines, online, car shows, etc... But if you do some research, I'm certain you'll find some comparisons.

From what I've read, I found its more of a matter of what you use your vehicle for. If you plan on getting rid of it every couple of years or you do a lot of mileage (thus changing your oil a lot), go conventional. Its cheaper and will maintain your engine. On the other hand, if you only put 3k a year on your car and only change the oil every year, go synthetic. It holds up longer than conventional and will maintain your seals and metal inside your engine a little better. It is true that it does get just as dirty but it does not break down as easily.

Just like anything, you get what you pay for... why not go the extra $20 a year (for me at least) if it keeps those seals soft?

 

[axlechassis]

The way I look at it, full synthetic oils like Mobil1 cost almost three times what dino-based oils cost.  If they can make my engine run three times longer, I'll pay for it.  I honestly can't see a 2F running for 600,000-900,000 miles between rebuilds, even if synthetic oil is used.  I would rather take the money I saved by using regular oil and spend it on a rebuild every 200k to 300k miles.

This kind off misses many points of using synthetics having your engine last 3 times as long is a happy result of using synthetics.
here are some of the other benefits:
cold starts are much easier less wear and tear on the starter and battery.
Flash point of synthetic oil is much higher than petroleum oil hence less combustion by product engine runs cleaner stays cleaner longer.
Synthetics are more resistant to acids and moisture buildups inside the engine. Extended drain intervals are indeed a reality. Petroleum motor oil after about 2500 miles begings to breakdown and literaly start to evaporate inside an engine leaving a amber varnish.
There are gains in fuel economy though not as significant.
The synthetic ATF's greases and gear lubes also have many benefits.
I've been using synthetics of different brands in a wide range of applications for many years. It would take a while for me to pass on all the xpierience I have with. One thing I notice with the majority of the posts on this subject is that they come from limited expeiriece and knowledge. One guy actually say's "while I'm no expert I just give you my opinion based on having read one obscure article". Give me a break!
Anyway specifically from my personal expeirience I would highly recomend the castrol syntech for your 2f engine after a nice long breakin period. As for grease, atf and gear lube I've been using the amsoil products for many years with very good results. I've also used Mobil1 for several applications also with very good results. There is alot of research on this subject out there that substantiates that these products are indeed quite superior to their petroleum based counterparts. I've got to go to work now.

 

[Sparky_Mark]

Not sure there is much merit to what was said to me, but I thought that I'd share it because it made sense...

I was told that it was true that synthetics provide better lubrucation, but it may be an issue with an engine that is as old as a 2F. He warned me that since the lubricant is superior to synthetics, it may get into places that could cause damage. He noted that there may be a chance that you could spin a main bearing since 2F are relatively "loose" engines.

Interesting comment... I'm not any sort of authority on the subject. I didn't take an IC engines class in college, nor P chem, but it sounded like there may be a valid issue there. Has anyone had a bad experience like this? What do you guys (and gals) think?

I found this discussion site and did some reading - arguments for synthetic...
http://forums.yellowworld.org/index.php?act=ST&f=39&t=1357&

Here's another site, I don't endorse this one, but I thought it brings up a big point: science and standardized testing (this is what makes me mad about "sales and marketing" people). Scroll down and look at the chapter headings. I may spend the $10 and download it.
http://www.motor-oil-engineers.com/


I say, "TEST IT AND SHOW ME DATA!"

 

[Trevor]

You are correct about the cold start advantages, I overlooked them since I live in the south and it is not a great concern to me. I am not denying the benefits of synthetics, they are superior to petroleum-based oils, however, in my mind the benefits DO NOT outweigh the additional costs. Almost all of the benefits that you listed lead to longer engine life, which returns us to my original comment. I could see how these benefits could make an engine run another 30k or 60k miles. But I don't believe the benefits you listed will make an engine run three times as long, thereby warranting the additional cost.

 

[sport]

I think that it depends on the vehicle. In my 97 4Runner I run Shell Rotella T synthetic and in the LC I use Havoline dino. Since I don't put that many miles on the LC, the cost synthetic is tough to justify. On the 4Runner where I put 20k a year on, it's crazy not to use synthetic. I also do extended oil changes that spread out the cost. Also, this is a subject that you should research very throughly. I ended up taking to a Chemical Engineer to come up with the two that I use.

Sport

 

[bjowett]

Porsche oil change interval - 15k miles, mobil 1.

Mobil 1 bottle once stated 25k mile change intervals (back in the 80's).

My oil changes? 12 - 18k, with a filter or 2 plus top off.

I once tried to kill an 87 16V Scirocco engine. Reasons? I wanted to upgrade the abused and well over 150k mile noisey liftered 1.8 to a 2.0L. 60k+ HARD miles with a few filter changes and top offs later, the tranny blew. The engine ran just as good, though the lifters made less noise. No smoke, no consumption.... Draw your own conclusions. It went to a friend for parts.

 

[Pete112]

I'm glad some people stuck up for synthetics... I was surprised before. I knew they were far superior!

What are you using for synthetic tranny and transfer case fluid? I don't remember coming across many of them.

 

[cruiser_guy]

I've heard that synthetics find any leaky seals better than mineral based oil so if you're putting it in the tranny/transfer make sure you have no leaks between the two (a common split case problem). I run Shell Syntec in my tranny/transfer and it seems to work well. I can't say I can notice any HUGE improvement though! I use standard mineral oil (Shell Rotella T 15W/40) in my 3B turbocharged diesel. I'll likely switch to straight 30W or 40W for the summer season.

 

[Guest]

Different Engine Oils that are Availible:
Mineral - Base Oil
Mineral - Base Oil / Mineral - Additive
Mineral - Base Oil / Synthentic - Additive
Synthetic - Base Oil / Synthetic - Additive

The best Oil and most Exspensive is Mineral - Base Oil / Mineral - Additive and is only avalible from Singapore.

The best Oil per Money is Mineral - Base Oil / Synthentic - Additive, that is made near where you live. eg. http://www.Penrite.com.au/ would be the best for me.

If it were possible to totally filter the Oil, Mineral would last for ever; But Synthetic will wear out.