Want to change the gear oil in my 60's manual trans, need 80w90, considering these two conventional oil options, not looking for synthetic (considered more appropriate and some report leakage with syn). Anyone have experience or a recommendation of one over the other? The Driven is a few dollars more per quart, not really an issue though, interested more in what's best.
PennGrade 1 Classic or Driven Racing Conventional GL-4 Manual Trans Gear Oil
- Thread starter ras61
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Welcome to BITOG 
Driven seems to cost twice as much as PennGrade, so I'd use the PG.
What kind of car is it?
Driven seems to cost twice as much as PennGrade, so I'd use the PG.
What kind of car is it?
I use this in my old manual transmission cars, shifting is fine, no mechanical issues after years of use. The boxes were all GM Muncies and I am not familiar with the design of your transmission but if the service / owner's manual is calling for a conventional GL4 this is good stuff. I can get it at US NAPA stores no problem.
https://www.crcindustries.com/products/api-gl-4-multi-purpose-gear-oil-1-gal.html
https://www.crcindustries.com/products/api-gl-4-multi-purpose-gear-oil-1-gal.html
Interesting, I like CRC products, will check it out, thanks
Would a 75w90 GL-5 work in your application?
I read somewhere on the internet that modern GL-5s have a "buffered" P/Su additive package that's yellow metal friendly.
I read somewhere on the internet that modern GL-5s have a "buffered" P/Su additive package that's yellow metal friendly.
I don't think I want to risk it, and frankly can get GL4 for pretty much the same price, so will just play it safe
This is what Redline recommends: https://www.redlineoil.com/mt-90-75w90-gl-4-gear-oil
Yes, pricy ($23 qt) but a good product that many folks use, but is synthetic and there's many reports of messy leaks in old transmissions (gets by seals, etc). Decided to go with the PennGrade Classic, after further research it's highly recommended by those that rebuild these transmissions - thanks for the help everyone!
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Synthetic won't cause a leak. I'd use the Amsoil, RedLine, MPT, or Ford 75w90 GL4. I would want the best protecting fluid along with the best shift quality, and I find the synthetics work the best.
https://vpracingfuels.com/product/vp-classic-gear-oil-gl-4-sae-80w-90/?c=394&
Year/make/model, transmission, fluid spec requirements, and location.. since possibly other grades might be more appropriate depending on location
I don't understand why some have a possibly classic/cool/collectible/sentimental vehicle, and want to use some conventional swill when there are premium synthetics.
https://vpracingfuels.com/product/vp-classic-gear-oil-gl-4-sae-80w-90/?c=394&
Year/make/model, transmission, fluid spec requirements, and location.. since possibly other grades might be more appropriate depending on location
I don't understand why some have a possibly classic/cool/collectible/sentimental vehicle, and want to use some conventional swill when there are premium synthetics.
I guess all the owners of these classic cars reporting leaks are just making up stories for fun, go to AustinHealey Exp and do a search? I'm not an engineer, but I listen to them, and the folks with decades of experience maintaining and rebuilding these old engines and tranies; if they say to use conventional oil instead of synthetic in the sump or gearbox that's fine with me. If synthetic is superior why does Valvoline have conventional VR1 for race cars? Driven developed by Joe Gibbs for racing and NASCAR also has conventional oil options. I have no doubts about being ignorant, so I'll let the experts determine the right product for the right application
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Most didn't even try to use synthetic.... they just keep blabbering the anti synthetic rhetoric from 30 years ago. Leaks are there. Synthetic costs more. That means its a more expensive drip that cheapskate owners cry about more often
Companies cater to demand, no matter how ignorant it is. Why does everyone gobble up unhealthy food that causes obesity, diabetes, heart disease, high blood pressure....... from the drive thru? I expect conventional oil to be around for many years. My favorite is watching owners buy PQIA failure oils at the local gas station, and poor it into their classics and muscle cars. Fools will always be fools.
If you have any leaks, fix it. Don't blame the oil. Its not 1970 anymore.
Companies cater to demand, no matter how ignorant it is. Why does everyone gobble up unhealthy food that causes obesity, diabetes, heart disease, high blood pressure....... from the drive thru? I expect conventional oil to be around for many years. My favorite is watching owners buy PQIA failure oils at the local gas station, and poor it into their classics and muscle cars. Fools will always be fools.
If you have any leaks, fix it. Don't blame the oil. Its not 1970 anymore.
MolaKule
Staff member
Synthetic MTF's do not cause leakage.
Leakage is caused by worn seals or cracked gaskets. Shaft seals finally wear out.
Excessive "wobbling" of shafts, due to worn bearings, can beat seals to death.
Insufficient swelling of seals around rotating shafts can result in leaks. Modern Synthetic MTF's have seal swell chemistry that exceeds any '60's technology.
In addition to the above, modern dedicated MTF's have friction modifiers for synchro-assemblies that many 60's oils did not have.
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Marketing works, along with a side of extrapolation from incorrect data.
Yes. Some are new here and some have been around a while.Wow, a lot experts here on 50-60 year old British transmissions
You’re new here, and asking questions. Let’s just say that MolaKule has been an industry formulator for many years and knows many of the “dark secrets” that led to a majority of what you’ve read on the internet against synthetics.Wow, a lot experts here on 50-60 year old British transmissions
You can put money on what MolaKule shares with you is true, regardless if he’s actually touched a 50-60 year old British transmission. BTW, what makes you think Joe Gibbs or anybody at Driven has touched one for you to call them experts? Just wondering…
What I've read is from multiple actual owners with actual experience. I don't doubt leaking is due to wear, but if you have an old trans with wear shouldn't you use the best product for that situation? And I'd bet the tolerances in these old gearboxes, with technology that goes back to the 50's if not the 40's, is a lot looser than what's made today. Bottom line is these same people with real world experience report a lot less leaking problems with conventional. If there's a way to use synthetic and prevent it from leaking please let me know.
Concerning Driven, all I know is they specialise in oils for all kinds of racing, old cars and new, including Nascar programs that spend and invest millions. But maybe the whole company is nothing more than a smoke and mirror act?
Yes I came here for advise, not a pissing match or an argument, so thanks and goodbye
So looser tolerances cause leakage?
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Looser tolerances... No no no no never
The word "synthetic" causes leakage. Worn out seals, transmissions, gaskets, and gargantuan wear looseness in the transmission, are never never never at fault. Just don't let the synthetic plumbing, synthetic flooring, or synthetic roofing, in my house learn about their required reputation since I might be living in a gusher from all directions.
Too many 'car forums' out there spewing bad info that so many eat up.
Being a 50-60 year old British transmission doesn't mean squat.
The word "synthetic" causes leakage. Worn out seals, transmissions, gaskets, and gargantuan wear looseness in the transmission, are never never never at fault. Just don't let the synthetic plumbing, synthetic flooring, or synthetic roofing, in my house learn about their required reputation since I might be living in a gusher from all directions.
Too many 'car forums' out there spewing bad info that so many eat up.
Being a 50-60 year old British transmission doesn't mean squat.