What's so special about gear oil that it's 70 bucks a gallon?

[Bram van den Heuvel]

What's so special about GL4 manual transmission gear oil that it's 70 bucks a gallon?

[clare]

You are looking at a high end synthetic oil. GL4 is getting a bit harder to find, but lots of GL5 for uder $25 a gallon in the USA - a bit more in Canada. Walmart USA carries LubKing GL4 90 weight for $32 a gallon.

[Bram van den Heuvel]

I'm told to get either Amsoil or Redline GL4 because it's for a Toyota W59 transmission with yellow metal that can be stripped off by GL5 additives (plus there are no hypoid gears in the manual transmission).

So it's going to be GL-4 but which one?

Even the Amsoil is $70 per gallon.

What's so special about these two fluids that makes them "worth" 70 dollars a gallon?

[Dean Hoffman]

Have you checked Amazon, NAPA, or farm supply stores like Tractor Supply, Rural King, or Orscheln? The first one that pops up at Amazon is $35.

[Ed Pawlowski]

Synthetics last longer and lubricate (reduce friction) better. Most of us don't need it but if you are planning yo keep the vehicle for a long time, use it under harsh conditions, it is worth the extra money.

Corvettes come from the factory with synthetic engine oil. The Cruze does not.

[Stormin' Norman]

The Redline can be purchased for as low as $56 / gallon through Amazon, with free shipping. See:

[Bram van den Heuvel]

I admit I'm running off of fear since all the Toyota guys say that you must use either Amsoil or Royal Purple or Redline GL4 75W90 in the manual transmission.

Even the Royal Purple 75W90 gear oil is $60 per gallon.

All I want to know is what's so special about these gear oils that they cost $60 to $70 a gallon (where I need about a gallon)?

Looking up the gear oils, I find technical information but nothing answers my question which is why I asked here.

A study of automotive gear lubes

[Stormin' Norman]

The specific products you mentioned above are all synthetic lubricants and cost more to manufacture, hence, they are more expensive at retail than their non-synthetic counterparts.

[Bram van den Heuvel]

I didn't realize these are "synthetics" as compared to whatever "normal" gear oil is. Is that what's so special about what everyone seems to recommend on the Toyota forum?

They all recommend mostly Redline, but sometimes Amsoil and less often Royal Purple, all of which are over $60 and closer to $70 per gallon.

Looking up what I'm supposed to use, I found this paper which said not to use GL5 and yet the Royal Purple is GL4/GL5 which this paper says is GL5.

All I'm looking for is information to make a decision as to what to put in a very old (decades) W59 Toyota 5-speed which has synchronizers and yellow metal.

[Bram van den Heuvel]

I think I have the answer as to "why" now, which is that the synthetics cost about $70 per gallon while the not synthetics cost about half that, at around $35/gallon.

But why, when motor oil is commonly half that still, is gear oil at even $35 per gallon, but much more importantly, what would be a reason to choose between the $35/gallon SAE 75W90 GL-4 gear oil versus the $70/gallon stuff.

Is it all due to synthetics? Are synthetics better for a two-decade old 5-speed manual transmission?

The reason I'm looking is that the shifting is getting harder to get into gear lately, so someone suggested putting the high end transmission fluid.

[Bill]

Forum "blowhard know-it-alls" are a dime a dozen. I use whatever the mfg recommends.

[Stormin' Norman]

Is the shifting problem your real issue? You are asking questions about why item A is more expensive than item B and that takes us off on tangents about refining, manufacturing, etc.

If you are having a shifting issue on your 20 year old transmission, I would start by thoroughly inspecting the clutch assembly including the actuator. There are a number of other reasons why the manual transmission might be hard to shift. You can start replacing things willy-nilly, but that gets expensive. It is far more logical to diagnose the actual cause of the problems.

[clare]

Rerally nothing of you don't need synthetic. All you NEED is a simple GL4 gear oil like the Walmart LubKing GL4. Synthetic doesn't thicken as much in the cold, or thin as much in the heat, and MAY last a little longer, but not enoughlonger to make it worth 4 times as much (there isGL4 oil available for as little as about US$16 a gallon)

[Ed Pawlowski]

One factor is volume. Regular motor oil is made in much larger quantities. I don't know about the differences in distilling and processing to comment about other factors.

It may help, but it may not do a damned thing. You have to find the real cause of the shifting problem. IMO, better lube will have minimal effect. It does not put metal back on worn parts, it does not straighten bent linkage.

You would get better results if you describe the actual problem. Hard to move the shift lever? Gears grinding? Synchronizer slow? Clutch adjustment? After 20 years a lot of things can be worn. Could be as simple as a worn pin in the linkage or as compex as main gears worn out.

[Bram van den Heuvel]

I was hoping to get good information like that so I thank you because all the guys on the Toyota forum are saying to only use Amsoil or Redline but they don't really know why.

I'm looking at GL4 and SAE 75W90 as those are the specs from Toyota.

My one question to you is if the synthetic doesn't thicken as much in the cold, how does it keep the 75W and if it doesn't thin out in the heat as much, how does it keep the 90 rating?

Isn't that what the rating is all about? So doesn't one 75W90 act the same at cold/hot as another 75W90?

[Scott Dorsey]

Well, then buy that.

There are plenty of cheaper GL4 oils out there. Most of the cheaper ones are not synthetics. They will not have sulfur additives that will damage nonferrous metals the way GL5 does. But, they also will not last as long and be as slick as the synthetics.

The synthetics are much more expensive. If they are formulated well, it is possible to make synthetics that cling to surfaces better, don't degrade as much with time, and keep junk in solution better. The Red Line will definitely do these things. Do you need any of these characteristics? I don't know, but it sounds like "all the Toyota guys" think you do.

That's not particularly expensive for a synthetic oil.

They are synthetic oils, actually genuine synthetics where the base oil materal has been made from a pure short-chain stock. Whereas natural petroleum oils are always going to be a mixture of paraffins, napthas, and napthalines no matter how well they are purified, these are pretty damn pure. But, it's more expensive to make an oil from ethylene gas than it is to take an existing oil and purify it.

If you think $70/gal is expensive, you should see what the high purity instrument oils for rebuilding speedometers costs.

The answer is mostly that a dollar isn't worth a dollar anymore. Back when gas was a quarter a gallon, gear oil cost about 25 times what gas did. Today gas is $2/gal. and gear oil costs about 25 times what gas does.

--scott

[Bram van den Heuvel]

Good point where the answer is that I'm going to change the 20-year-old oil anyway, just in case that solves the shifting problem and even if it doesn't solve the shifting problem, it's well past its due date, don't you think?

So, I have two separate (but combined) issues which are that I have a shifting problem getting into gear when the clutch seems to be engaging OK (a bit late in the pedal arc, but still ok) and where it's time to change the gear oil.

I'll probably do the differential at the same time but that's a different question because I think that takes GL5.

I agree with you so that's why I would like this thread to just be how to intelligently choose the transmission gear oil for a twenty-year-old transmission.

[Scott Dorsey]

The problem with older cars is that what the manufacturer recommended has likely been unavailable for decades.

We have this issue with motor oils that don't have the ZDDP levels that older lifter designs expected.

--scott

[clare]

When I put synthetic in my ranger it GOT hard to shift

[clare]

I was a Toyota service manager for a long time. Synthetic NOT REQUIRED