Oil: I'm Not Convinced It Ever Needs To Be Changed

WilliamBos · Sep 16, 2012

I completely agree. The more I hear of extended intervals, aftermarket programmers, and the like, the more I would rsther bite th bullet and buy new. I would be the same lucky guy to have it blow up on me. No thanks.

Deere Dude said:
This thread kind of reassures me to always buy new, unless I know the owner. I had an acquaintance who bragged about hardly ever changing his oil in his car and that he never greased the front end joints (Back when cars had greaseable joints) and that the car had 130,000 miles on it. The body looked fine and nothing was breaking down, so he figured he must be doing something right. It would be my luck to buy one of those cars or tractors that look good on the outside but ready to fall apart on the inside.

ray66v · Sep 17, 2012

CBW1999 said:
........he who lives near Barlows- trades often.

Slight shift in the conversation- any difference in trans/hydraulic fluid? does "it" ever need to be changed? You mention earlier owners manuals having it part of the 50 hour service but not currently. Although not part of internal combustion, it is still subjected to high heat. Interestingly enough, the "hydro" transmission in my toro 217-d, uses 10w30 not hydraulic fluid. This is where I get utterly confused........

Same unit, the gear box for the mower deck uses 30w, not gear oil.

My dad's Landpride zero turn used 30w in the hydros. I have concluded, the only reason they do this that makes sense, is for their convenience.

Sure, the engine oil works. But hydraulic trans oil has an additive package that is made for hydros, 10w30, or 30w is certainly not going to do a better job.

So far, I have not heard of a manufacturer objecting to swapping the 10w30, or 30w oil, for hydraulic trans oil, in a hydro. Landpride didn't, so we did.

Same for the gear boxes, there are additives in the gear oil that make it much better at protecting your gears than engine oil, or hydraulic trans oil, because that's all gear oil has to do.

Recently, someone posted that MF had stopped using hydraulic oil, in the front diff of their compact tractors. Although, their manual did offer the option of switching to gear oil when servicing it.

I am extending the interval on my my hydraulic trans oil. I switched it to synthetic, and don't run it in dirty conditions, so I don't see a need to replace it.

CBW1999 · Sep 17, 2012

Well then, I guess i'll switch fluid type in the spring tune up.

I have such a hard time balancing my inner woes- I hate having to keep a bunch of different fluid types around to serve the same function but in different equipment. I also hate the possibility of screwing something up.

The Toro is a 1986 commercial grounds keeping unit I got for free because it needed work. I suppose i can't do much worse to it than it has already been through!

SDT · Sep 17, 2012

Nonsense.

SDT

ccsial · Sep 17, 2012

ray66v said:
My mom has a North Star V8, which from the day it was made, uses a quart of oil every 500 miles, (GM said that is acceptable). At that rate of replenishment, I suppose you could consider it a continuous oil change. :confused3:

This is interesting. One of my customers had the same problem on North Star V8 Caddy. He finally insisted they do somthing or he would sue. After they tore down the engine they found one cylinder with no rings. He got a new engine.

megaboz · Sep 17, 2012

SDT said:
Nonsense.

SDT

So very helpful. Not.

OK, so back to topic. Changing to a different fluid may not hurt the gears, but could have an affect on seals.

Extended drain intervals in most case won't hurt, unless your definition of extended is your life time.

Oils get dirty from combustion of the engine and other environmental conditions. Based on situations, you may need to adjust to the situations.

I know first hand that some older engines may last 200k mileage wise without oil changes, but I wouldn't temp fate for a long trip with such an engine. But I would consider 200k abuse and not an extended drain interval.

ray66v · Sep 17, 2012

ccsial said:
This is interesting. One of my customers had the same problem on North Star V8 Caddy. He finally insisted they do somthing or he would sue. After they tore down the engine they found one cylinder with no rings. He got a new engine.

Her Deville has almost 80k on it now, I have to assume it would have failed by now, if that was the case.

Conversely, the Nissan engine in my Villager has 208,000 miles on it, and it has never used a single drop of oil.

94BULLITT · Sep 17, 2012

ccsial said:
This is interesting. One of my customers had the same problem on North Star V8 Caddy. He finally insisted they do somthing or he would sue. After they tore down the engine they found one cylinder with no rings. He got a new engine.

Those Northstar engines are junk. When you change the coolant in them you have to use gm sealant tabs in them or you will have a leak.

crazyal · Sep 17, 2012

newbury said:
I've been reading BTOG and I think you have the synthetics and mineral oil characteristics reversed.http://www.bobistheoilguy.com/motor-oil-103/

and

My TDI runs a synthetic and the oil change interval is 10,000 miles. Per VW. My F350 runs either with a mfg recommended interval of 5,000, but it looks like I could run mineral oil 8,000 miles and I'm waiting to find out my expectancy on synthetic.

I've read what he wrote and it's not the way I was taught (I'm not saying he's wrong). I started thinking he could be right but then he put this in the middle of his "motor oil 103".
"At temperatures below zero you will not be able to start your car with mineral oils while the synthetic oils may be used to -40ï½° or -50ï½°F. Oils are so thick that the normal method of viscosity measurement is not possible. Instead we measure if the oil can even be pumped or poured. Again, we are only discussing a single category of oil, the multi-grade 10W-30 API / SAE grade."

You're from Vermont, did you ever start your car on a -30° or -40° morning with non synthetic motor oil? I know I have.

Oil gets thicker with age, even Bob agrees (it's on that same page). Bob doesn't go into detail as to why it gets thicker or if he does I missed it. Bob talks about waxes that thicken in cold weather but that's not due to age. What I was taught is that conventional oil is made up of different size molecules while all the molecules in synthetic oils are the same size. The smaller the molecule the easier it will burn off. In conventional oil that will leave the larger ones behind thus making the oil thicker. Some of the additives are design to slow this down from happening and other chemical changes that thicken the oil from happening.

Bob could be right, clearly I'm not an expert. When I read his motor oil university I found it lacking. It seams like he focuses on new oil. I couldn't find much of anything going into detail as to why he thinks oil gets thicker with use. If you can find it, please post a link.