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Wildthings
Samba Member
Joined: March 13, 2005
Posts: 52376
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 Posted: Thu Feb 04, 2010 12:48 pm Post subject: |
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| Wildthings wrote: |
| raygreenwood wrote: |
Many folks in the far north do indeed use ATF in their trannys....but are you sure they drain them in the spring and refill them with 90 weight...or are you just assuming that they do?
Most places where this is necessary at all.....do not get much warmer than 40F in the summer....and are freezing again at night.
Also...I know for absolute 100% fact....that ATF WILL destroy the EP lubricity of hypoid gear oil. Been there...done that...several times. |
Gets a lot hotter than that in much of the north country and there is no night for many months so there isn't much in the way of freezing to be had.
ATF will run fine in these boxes, even in much warmer climes. I have run ATF in both 091s and 091-1 that had existing synchronizer problems and were hard to get into gear when running the spec oils. Each of the boxes I have done this to have gotten over 150K miles of additional service, or are still in service. More recently I have gone to running 0W-40 motor oil in lieu of the ATF.
BTW there are GL-4 rated ATF's available these days as well. |
| Greenwood wrote: |
| Running 0-W 40 as auto tranny fluid is not a great idea either. Why?...because though it performs the hydraulic function perfectly well (a fluid is a fluid in that respect), real dedicated auto tranny fluids must resist oxidization, hydraulic shear thinning and oil film failure at temperatures over 450F in the torque converter (in not so odd cases 550F is common). There are no 0-W 40's that meet the temperature and viscosity control level for automatic transmissions. These are some of the hall marks of automatic transmission fluids and why there are so many specific ones. ATF...does not shear-thin or heat thin in exactly the same manner as motor oil. |
Wow, suddenly my 091s and 091-1s have become autoboxes. Nobody mentioned anything about running motor oil in the automatic transmission section of an automatic. I worked in a transmission shop long enough years ago to have a good feel for what standard hypoid gear lubes often do to manual trannys. I don't care what the books say to use, that stuff will often fry the H out of a tranny whereas a tranny in the same service that is filled with motor oil typically looks beautifully clean inside when taken apart. I don't think that I have used hypoid gear lube in any of my non transaxle manual trannys in the last 20 years. As for manual transaxles I am well on my way to eliminating all hypoid gear lube there as well, though the use of a GL-4 rated ATF sounds tempting. If I do swap to a GL-4 rated ATF I won't be able to really give a good opinion for a decade or so, so don't wait up. |
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SGKent 
Samba Member
Joined: October 30, 2007
Posts: 42612
Location: at the beach
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| Posted: Thu Feb 04, 2010 3:44 pm Post subject: |
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| Quote: |
| No...metal filings like that are NOT normal. You should have little or no normal wear on gear faces. The only real wear parts in the tranny....if its running well....are non-magnetic. Those look like what you get when you have destroyed bearing cages. |
It is reasonably normal to have ferrous debris in a trans. Most Synco hubs are ferrous and although the brass cones engage, there is some wear on the hubs. Also where the shifter forks ride the hubs there can be ferrous wear. Last small itsy bitsy parts wear on the gears over time and that shows up too on the magnetic trap.
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Last edited by SGKent on Thu Feb 04, 2010 5:24 pm; edited 1 time in total |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 23153
Location: Oklahoma City
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| Posted: Thu Feb 04, 2010 3:47 pm Post subject: |
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| Wildthings wrote: |
| Wildthings wrote: |
| raygreenwood wrote: |
Many folks in the far north do indeed use ATF in their trannys....but are you sure they drain them in the spring and refill them with 90 weight...or are you just assuming that they do?
Most places where this is necessary at all.....do not get much warmer than 40F in the summer....and are freezing again at night.
Also...I know for absolute 100% fact....that ATF WILL destroy the EP lubricity of hypoid gear oil. Been there...done that...several times. |
Gets a lot hotter than that in much of the north country and there is no night for many months so there isn't much in the way of freezing to be had.
ATF will run fine in these boxes, even in much warmer climes. I have run ATF in both 091s and 091-1 that had existing synchronizer problems and were hard to get into gear when running the spec oils. Each of the boxes I have done this to have gotten over 150K miles of additional service, or are still in service. More recently I have gone to running 0W-40 motor oil in lieu of the ATF.
BTW there are GL-4 rated ATF's available these days as well. |
| Greenwood wrote: |
| Running 0-W 40 as auto tranny fluid is not a great idea either. Why?...because though it performs the hydraulic function perfectly well (a fluid is a fluid in that respect), real dedicated auto tranny fluids must resist oxidization, hydraulic shear thinning and oil film failure at temperatures over 450F in the torque converter (in not so odd cases 550F is common). There are no 0-W 40's that meet the temperature and viscosity control level for automatic transmissions. These are some of the hall marks of automatic transmission fluids and why there are so many specific ones. ATF...does not shear-thin or heat thin in exactly the same manner as motor oil. |
Wow, suddenly my 091s and 091-1s have become autoboxes. Nobody mentioned anything about running motor oil in the automatic transmission section of an automatic. I worked in a transmission shop long enough years ago to have a good feel for what standard hypoid gear lubes often do to manual trannys. I don't care what the books say to use, that stuff will often fry the H out of a tranny whereas a tranny in the same service that is filled with motor oil typically looks beautifully clean inside when taken apart. I don't think that I have used hypoid gear lube in any of my non transaxle manual trannys in the last 20 years. As for manual transaxles I am well on my way to eliminating all hypoid gear lube there as well, though the use of a GL-4 rated ATF sounds tempting. If I do swap to a GL-4 rated ATF I won't be able to really give a good opinion for a decade or so, so don't wait up. |
Because of this quote...........More recently I have gone to running 0W-40 motor oil in lieu of the ATF.
I thought you were stating that you were now running 0-W-40 in place of ATF in autoboxes.
My mistake.....and I believe I mentioned that possibility down below....right here as a matter of fact, when I said this..............
"If you were speaking of using synthetic 0-W-40 in the differential section....thats actually a better idea than using ATF"
By differential section, I mean in any differential section for cold weather.
Hypoid lube ..."fry the heck out of the inside of a transmission"?...in what respect? Surface case corrosion is the only vague possibility of that...and that only happens when hypoid oil entrains moisture. That only happens when its used in very humid environments and never gets fully warmed up. Change it more often.
Other than that....what parts are we speaking of "frying"? Don't confuse "shiner" because of detergent properties with properly protected for extreme pressure...which no motor oil on this planet is listed for.
I will ride along on this one and say....you seem to be pretty well versed on what you have figured out to be excellent lubricnats that work for you.
The vast majority of those reading this.....including the gentleman who started the thread are not. Do you want to give this level of specialized lube advice right here wit hteh vast potential of not getting it right?
Maybe you should read up on a few things (i'm not being rude...I had to read up and I'm still not fully up on the world). What I am trying to point out is that there are various additives that do various things in manual transmissions.
The GL ratings are NOT for viscosity they are for EP modifier ratings. Gl-4 and other GL rated oils have no specific viscosity ratings whatsoever. EP additives (extreme pressure additives for hypoid gearing)...generally are also corrosive to the synchro mechanisms. Correct fluids for the use of manual transmissions MUST have the anti-corrosion inhibitors....that GL-4 ATF's ...do need or have. Here is an excerpt I picked up on line that I will find who stated if I can.
Pay close attention to the highlighted areas:
Most GL5 differential and GL4 Manual Transmission oils contain sulfur-phosphorous EP packages. GL4 does NOT refer to any specific viscosity, but it refers to a level of AW/EP protection for the gearing and bearings in a transmission. GL4-rated oils contain about 40% to 60% of the EP additives that GL5 oils contain.
Both differential and manual transmission fluids use chemical compounds that subdue or inhibit the corrosive effects of sulfur and phosphorous such as calcium, magnesium, boron, potassium or other basic compounds. Emulsifiers, corrosion and rust inhibitors also are included to do their respective jobs.
GL5 differential lubes use friction modifiers to reduce mechanical and fluid friction and add some anti-shudder friction modifier for limited slip, both very different chemical compounds.
Manual Transmission fluids use a different friction modifier for synchro engagement, a modifier that does NOT contain the same Friction Modifier chemicals as differential lubes. (Ray edit: they are talking about modern manuals seperate from differentials... not ours)
Most manual transmission "specific" fluids (GL4) contain about 40% to 60% of the EP additive of differential lubes (GL5) with inactive or buffered sulphurs. GL4 has come to infer a gear lube with the above percentages of EP additive. The exception of course is ATF fluid used in some of the newer transmissions.
Therefore, both lubes contain the same EP additives, just in different strengths or additive ratios.
Ever since the synchromesh-type fluids appeared on the scene (such as the GM Synchromesh fluid), drivers have had better shifting due to better synchro engagement, attributed to the specialized friction modifier used in these lubes. This specialized friction modifier is better for metallic and composite synchros in terms of shifting and life.
Manual Transmission fluids use a different friction modifier specifically designed for synchro engagement, a modifier that does NOT contain the same chemical compounds as do differential lubes.
A synchromesh fluid usually refers to a specialized fluid that contains special friction modification additives for transmissions that use mechanical synchronizer assemblies; those synchronizer assemblies may be made of carbon fiber composites, sintered metal.
[b]You also have to consider the viscosity of the fluid that the transmission was designed for. The spectrum now ranges from ATF to 75W90 viscosities and therefore a synchromesh GL4 Manual Transmission Lubricant (MTL) can be any viscosity from 7.0 cSt (ATF equivalent viscosity) to a 75W90 type viscosity of approx. 14.5 cSt, and contains special friction modification additives for synchronizer assembly engagement.
brass/bronze, or steel-steel materials. [/b]
Current MTL GL4 viscosites are:
1. ATF Series - Type; 6.5 to 8.5 cSt (Equivalent ATF viscosity; Note: ATF additive package is weak compared to most GL 4's)
2. Synchromesh Series -Type; 9.3 - 9.5 cSt (such as Amsoils MTF, Texaco's MTL, Pennzoil's Synchromesh, GM and Chrysler's Synchromesh)
3. 75W85 Series-Type; 9.8 to 11.5 cSt ( Redline's MTL, RP's Synchromax LT, Nissan's MTL, Honda MTL, Castrol Syntorq LT)
4. 75W90 Series-Type; 12.8 to 14.5 cSt (Amsoil's MTG, Redline's MT-90).
MTL specific lubes we're developed for manual tranny's and transaxles, and not for differentials or industrial gear boxes. A differential lube may not kill your tranny, but it is not the optimum lube for it. A diffy 75W90 (GL5) usually has a higher viscosity than does an mtl in the same advertized weight.
All I'm saying....is that with the potentially rusted ass gear box this gentleman has....which could mean pitted bearings, needles, gear faces etc......using a fluid of a viscosity that the box was not designed for is not optimum.
GL-4 ATF fluids...I am not that knowledgeable about....but what I do know is that "GL-4"...does notspecify viscosity....and viscosity is very important with a hypoid gearbox. Also bear in mind...that many front drive transmissions are NOT hypoid gearing and can use a much differnt oil package than a hypoid box like ours. I'm just stating that....in case anyone gets the idea that they can use the same GL-4 manual gearbox lubricant that their modern car uses. It aint necessarily so.
I am actually impressed that they make ATF's with GL-4 ratings of EP additives. I learn something new all the time. I still would not use them in my gearbox unless I could verify viscosity and anti-corrosion properties for ALL of the parts in the box.
Its also worth it bear in mind.....while reading that excerpt....that the gentleman writing is largely speaking of American rear drive cars. You can tell this because he notes.....differences in oils for differentials...and manual gearboxes. In any car with a rear drive and seperate differential from the gear exchange box...you can run whatever is friendliest inside with the gears. many are straight cut and the rest are skew bevel....none of them are semi-hypoid (types 1,2,3) or fully hypoid (type 4 and autobox type 3 and 4). because of having both types of gears in our transmissions...we have to have specific viscosities and additive packages. We run differntial oil through the whole thing.
Oh! found it. this is a great thread. you should read it all. There are lots of wear and EP concerns with using ATF's in manual trannys. Ray
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1231182 |
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Malokin Martin
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Joined: August 19, 2007
Posts: 3281
Location: E-burg
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| Posted: Thu Feb 04, 2010 5:22 pm Post subject: |
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| ratwell wrote: |
| The metal on the magnet is more than normal for 100k miles. |
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SGKent
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Joined: October 30, 2007
Posts: 42612
Location: at the beach
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| Posted: Thu Feb 04, 2010 5:30 pm Post subject: |
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re RAtwell - I can't read Richard's mind but this is my best GUESS what he meant:
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