GL-4 vs GL-5
01-18-2010, 06:50 AM
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GL-4 vs GL-5
I'm in the process of draining my manual transmission oil and refilling it. I searched a few different auto stores and could only find GL-4 gear oil. I saw a lot of threads here where people recommend gl-4 over gl-5. Why is gl-4 any better? I was google searching and found various answers for other brands, but nothing related to the reason Toyota drivers use gl-4. The reason I read was that it makes shifting too sloppy or it does something to the synchros.
Any info?
Any info?
01-18-2010, 07:32 AM
#2
There was a discussion on here not too long ago about this. I think historically GL-5 oils had additives that were harsh toward the brass in the synchros but it may or may not be the case today. Just run a high-quality gear oil of either flavor and trust in Toyota's overengineering to make it last.
01-18-2010, 08:29 AM
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One is not better than the other, they have some different uses based on the materials in the transmissions, gears, etc. Just use what the manual says, which I seem to recall is GL-4 for the transmission.
01-18-2010, 08:30 AM
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I got Valvoline 75w90. It was that, or Mobil for $20 a quart or royal purple for $20 a quart. I wanted to see how GL-5 worked before I spend that money on another Gl-5 brand that's 4 times the cost. I also heard redline is good, but the motorcycle/bike store that deals it was out of stock and I didn't feel like hunting all day for redline AND Gl-4.
01-19-2010, 04:10 PM
#7
I bought some of that stuff from NAPA. It's fine...a little heavy on the low end weight though for these transmissions. The only noticeable difference there is how much longer it takes for my transmission to get warmed up on really cold mornings with the 85W vs. 75W-90. So it shifts a little stiffer into 2nd & 3rd for a few miles or so with the 85W(vs. a few blocks with the 75W). No big deal.
Sidenote: I switched from synthetic to that stuff. Didn't notice a huge difference, so I've been runnin' it for awhile just to make use of my money. I might switch back to some of the synthetic GL-6 for manual transmissions from Richmond Gear.
http://en.wikipedia.org/wiki/Gear_oil
http://www.lubrizol.com/DrivelineAdd...arOil/GL5.html
Sidenote: I switched from synthetic to that stuff. Didn't notice a huge difference, so I've been runnin' it for awhile just to make use of my money. I might switch back to some of the synthetic GL-6 for manual transmissions from Richmond Gear.
API GL-4, oils for various conditions - light to heavy. They contain up to 4.0% effective antiscuffing additives. Designed for bevel and hypoid gears which have small displacement of axes, the gearboxes of trucks, and axle units. Recommended for non-synchronized gearboxes of US trucks, tractors and buses and for main and other gears of all vehicles. These oils are basic for synchronized gearboxes, especially in Europe.
API GL-5, oils for severe conditions. They contain up to 6.5% effective antiscuffing additives. The general application of oils in this class are for hypoid gears having significant displacement of axes. They are recommended as universal oils to all other units of mechanical transmission (except gearboxes). Oils in this class, which have special approval of vehicle manufacturers, can be used in synchronized manual gearboxes only. API GL-5 oils can be used in limited slip differentials if they correspond to the requirements of specification MIL-L-2105D or ZF TE-ML-05. In this case the designation of class will be another, for example API GL-5+ or API GL-5 LS.
API GL-6, oils for very heavy conditions (high speeds of sliding and significant shock loadings). They contain up to 10% high performance antiscuffing additives. They are designed for hypoid gears with significant displacement of axes. Class API GL-6 is not applied any more as it is considered that class API GL-5 well enough meets the most severe requirements.
API GL-5, oils for severe conditions. They contain up to 6.5% effective antiscuffing additives. The general application of oils in this class are for hypoid gears having significant displacement of axes. They are recommended as universal oils to all other units of mechanical transmission (except gearboxes). Oils in this class, which have special approval of vehicle manufacturers, can be used in synchronized manual gearboxes only. API GL-5 oils can be used in limited slip differentials if they correspond to the requirements of specification MIL-L-2105D or ZF TE-ML-05. In this case the designation of class will be another, for example API GL-5+ or API GL-5 LS.
API GL-6, oils for very heavy conditions (high speeds of sliding and significant shock loadings). They contain up to 10% high performance antiscuffing additives. They are designed for hypoid gears with significant displacement of axes. Class API GL-6 is not applied any more as it is considered that class API GL-5 well enough meets the most severe requirements.
What’s the difference?
The performance requirements for automotive gear lubricants depend on their intended use.
API Category GL-1 (inactive*) designates the type of service characteristic of manual transmissions operating under such mild conditions of low unit pressures and minimum sliding velocities, that untreated oil may be used satisfactorily. Oxidation and rust inhibitors, defoamers and pour depressants may be used to improve the characteristics of lubricants intended for this service. Friction modifiers and extreme pressure additives shall not be used.
API Category GL-2 (inactive*) designates the type of service characteristic of automotive type worm-gear axles operating under such conditions of load, temperature and sliding velocities, that lubricants satisfactory for API GL-1 service will not suffice.
API Category GL-3 (inactive*) designates the type of service characteristic of manual transmissions and spiral-bevel axles operating under mild to moderate to severe conditions of speed and load. These service conditions require a lubricant having load-carrying capacities greater than those that will satisfy APL GL-1 service, but below the requirements of lubricants satisfying the API GL-4 service.
API Category GL-4 designates the type of service characteristic of spiral-bevel and hypoid gears in automotive axles operated under moderate speeds and loads. These oils may be used in selected manual transmission and transaxle applications.
API Category GL-5 designates the type of service characteristic of gears, particularly hypoids in automotive axles under high-speed and/or low-speed, high-torque conditions. Lubricants qualified under U.S. Military specification MIL-L-2105D (formerly MIL-L-2015C), MIL-PRF-2105E and SAE J2360 satisfy the requirements of the API GL-5 service designation.
API Category GL-6 (inactive*) designates the type of service characteristic of gears designed with a very high pinion offset. Such designs typically require (gear) score protection in excess of that provided by API GL-5 gear oils. The original API GL-6 test equipment is obsolete.
API Category MT-1 designates lubricants intended for non-synchronized manual transmissions used in buses and heavy-duty trucks. Lubricants meeting API MT-1 provide protection against the combination of thermal degradation, component wear, and oil seal deterioration which is not provided by lubricants meeting only the requirements of API GL-4 and API GL-5.
MIL-PRF-2105E this specification released in 1995 combines the performance requirements of its predecessor (MIL-L-2105D) and API MT-1. MIL-PRF-2105E maintains all existing chemical/physical requirements, stationary axle test requirements, field test requirements and data review by the Lubricants Review Institute that were required under MIL-L-2105D. It also adds the stringent oil seal compatibility and thermal durability test requirements under API MT-1. MIL-PRF-2105E has been re-written as SAE Standard J2360.
SAE J2360 standard is a new global quality standard that defines a level of performance equivalent to that defined by MIL-PRF-2105E, a U.S. military standard for approval that was not available to oil blenders in all parts of the world. It includes all of the most recent axle and transmission testing requirements identified in API GL-5, API MT-1, and MIL-PRF-2105E including the need to demonstrate proof-of-performance through rigorous field testing.
* API Categories GL-1, GL-2, GL-3 and GL-6 were declared inactive by SAE Technical Committee 3 in 1995, even though oils may be marketed with these designations. Similarly, ASTM does not plan to maintain the performance tests associated with these categories, as in a number of cases these tests can no longer be run because parts or test installations are not available.
The performance requirements for automotive gear lubricants depend on their intended use.
API Category GL-1 (inactive*) designates the type of service characteristic of manual transmissions operating under such mild conditions of low unit pressures and minimum sliding velocities, that untreated oil may be used satisfactorily. Oxidation and rust inhibitors, defoamers and pour depressants may be used to improve the characteristics of lubricants intended for this service. Friction modifiers and extreme pressure additives shall not be used.
API Category GL-2 (inactive*) designates the type of service characteristic of automotive type worm-gear axles operating under such conditions of load, temperature and sliding velocities, that lubricants satisfactory for API GL-1 service will not suffice.
API Category GL-3 (inactive*) designates the type of service characteristic of manual transmissions and spiral-bevel axles operating under mild to moderate to severe conditions of speed and load. These service conditions require a lubricant having load-carrying capacities greater than those that will satisfy APL GL-1 service, but below the requirements of lubricants satisfying the API GL-4 service.
API Category GL-4 designates the type of service characteristic of spiral-bevel and hypoid gears in automotive axles operated under moderate speeds and loads. These oils may be used in selected manual transmission and transaxle applications.
API Category GL-5 designates the type of service characteristic of gears, particularly hypoids in automotive axles under high-speed and/or low-speed, high-torque conditions. Lubricants qualified under U.S. Military specification MIL-L-2105D (formerly MIL-L-2015C), MIL-PRF-2105E and SAE J2360 satisfy the requirements of the API GL-5 service designation.
API Category GL-6 (inactive*) designates the type of service characteristic of gears designed with a very high pinion offset. Such designs typically require (gear) score protection in excess of that provided by API GL-5 gear oils. The original API GL-6 test equipment is obsolete.
API Category MT-1 designates lubricants intended for non-synchronized manual transmissions used in buses and heavy-duty trucks. Lubricants meeting API MT-1 provide protection against the combination of thermal degradation, component wear, and oil seal deterioration which is not provided by lubricants meeting only the requirements of API GL-4 and API GL-5.
MIL-PRF-2105E this specification released in 1995 combines the performance requirements of its predecessor (MIL-L-2105D) and API MT-1. MIL-PRF-2105E maintains all existing chemical/physical requirements, stationary axle test requirements, field test requirements and data review by the Lubricants Review Institute that were required under MIL-L-2105D. It also adds the stringent oil seal compatibility and thermal durability test requirements under API MT-1. MIL-PRF-2105E has been re-written as SAE Standard J2360.
SAE J2360 standard is a new global quality standard that defines a level of performance equivalent to that defined by MIL-PRF-2105E, a U.S. military standard for approval that was not available to oil blenders in all parts of the world. It includes all of the most recent axle and transmission testing requirements identified in API GL-5, API MT-1, and MIL-PRF-2105E including the need to demonstrate proof-of-performance through rigorous field testing.
* API Categories GL-1, GL-2, GL-3 and GL-6 were declared inactive by SAE Technical Committee 3 in 1995, even though oils may be marketed with these designations. Similarly, ASTM does not plan to maintain the performance tests associated with these categories, as in a number of cases these tests can no longer be run because parts or test installations are not available.
Last edited by MudHippy; 07-26-2010 at 12:08 PM.
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01-19-2010, 04:45 PM
#8
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GL-5 oils are more slippery, and often don't work well with the synchros, leading to hard shifting. My tranny shifted MUCH easier after switching from a GL-5 to Red Line MT-90. The other factor is that there is a sulphur compound in most GL-5 products that corrodes the brass synchros.
Yet another factor is cold weather performance. The GL-5s are thicker, and the mineral GL-5s are A LOT thicker in the cold. They don't flow anywhere near as well as the MT-90: https://www.yotatech.com/forums/f116.../#post51338384
The differentials need a GL-5. Transfer case can use either; for very cold winters use the MT-90 but in mild winters use GL-5 for a bit better protection.
Yet another factor is cold weather performance. The GL-5s are thicker, and the mineral GL-5s are A LOT thicker in the cold. They don't flow anywhere near as well as the MT-90: https://www.yotatech.com/forums/f116.../#post51338384
The differentials need a GL-5. Transfer case can use either; for very cold winters use the MT-90 but in mild winters use GL-5 for a bit better protection.
Last edited by sb5walker; 01-19-2010 at 04:47 PM.
01-20-2010, 11:40 AM
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GL-5 has nothing to do with the weight of the oil. It is related to sliding forces, such as found in a ring and pinion.
Toyota (and dealers) use GL-5 dino oil in diffs, transfer cases, and trannies all the time (Pennz, Valvoline, etc.). No problem, though GL-4 is a better choice for trannies due to the 'gription' needed by the synchros. HOWEVER, when you get into synthetic oils, the GL rating starts making a big difference, and so does the manufacturer.
With synth, use GL-4 in the trannies, and of course nothing BUT GL-5 in the diffs. The tcase doesn't care (no ring gear and no synchro).
I used Pennz synthetic GL-4 in the tranny as an experiment and got disastrous (and expensive) performance. Mobil1 80W90 (GL-5) also sucked. Redline MT90 was great, and so was plain ol' dino 80W90 GL-5.
I run Redline MT90 FWIW. Very little will make an R151 shift like a sportscar tranny, but Redline does fine.
Toyota (and dealers) use GL-5 dino oil in diffs, transfer cases, and trannies all the time (Pennz, Valvoline, etc.). No problem, though GL-4 is a better choice for trannies due to the 'gription' needed by the synchros. HOWEVER, when you get into synthetic oils, the GL rating starts making a big difference, and so does the manufacturer.
With synth, use GL-4 in the trannies, and of course nothing BUT GL-5 in the diffs. The tcase doesn't care (no ring gear and no synchro).
I used Pennz synthetic GL-4 in the tranny as an experiment and got disastrous (and expensive) performance. Mobil1 80W90 (GL-5) also sucked. Redline MT90 was great, and so was plain ol' dino 80W90 GL-5.
I run Redline MT90 FWIW. Very little will make an R151 shift like a sportscar tranny, but Redline does fine.
01-20-2010, 01:21 PM
#11
Well put!
I'll verify that the R150F ain't no sports car shifter either. It don't matter what oil's in it. Some oils are just slightly better shift quality wise I've noticed. Having tried quite a few different kinds myself. I'm leaning more toward synthetic these days to try and make the internals last vs. how good I want it to shift, or not...
01-20-2010, 01:46 PM
#12
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Check www.bobistheoilguy.com
read all about the differences
read all about the differences
01-20-2010, 02:49 PM
#13
I just recently had some issues with my transmission and having hard shifting, especially in the winter. I had been running Mobil 75-w90 in it and when it was really cold it just had a really hard time getting into the gears so as I searched I read that a lot of guys liked the MT-90 and other GL-4 fluids. So after some research I found some BG synchroshift II which is a GL-4 75-w80 which as you know from the oil weight numbers it it significantly lighter in winter-time temps. I called BG just for the heck of it and told them about the symptoms I was having and they said that the 75-w90 was just too thick in the cold and second of all that the Mobil wasn't really designed to be in ALL transmissions, which I found was very interesting. Not only that but they told me that if you have a new vehicle and you document that you have always ran their product through your transmission that they will warranty your transmission. Now I'm sure there is some fine print on this "warranty" but I thought that was pretty unusual. Anyways I put the stuff in my tranny and overfilled just a little and I have to say that in the cold it shifts much much better. My transmission have like 230,000 miles on it and has never been worked on and I think I can feel that Ill need some synchros someday, but I have to say this fluid really did help.
01-21-2010, 05:21 AM
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I am a firm believer in BG products. Few other similar products, if any, make the mark IMHO. This is from experience with motorcycle engines primarily, and real temperature reduction. BMW endorses NO aftermarket additives... except BG. Or that was the story with the older aircooled motors. I also experienced noticeable temperature reduction in a hot blooded Honda motor. Said all that to say this... you cannot go wrong with BG IMHO. I won't use any other additives**.
Redline MTL is a lighter version of MT90 and would also help in winter. Roger Brown says it is a tad noisier though.
**[edit] well, I have considered using Ford Friction Modifier to help my R151 shift more like a sportscar tranny... LOL (based on a conversation with Marlin). I understand I will need a noseplug when I do it. ;-)
Redline MTL is a lighter version of MT90 and would also help in winter. Roger Brown says it is a tad noisier though.
**[edit] well, I have considered using Ford Friction Modifier to help my R151 shift more like a sportscar tranny... LOL (based on a conversation with Marlin). I understand I will need a noseplug when I do it. ;-)
Last edited by Red_Chili; 01-21-2010 at 05:24 AM.
07-25-2010, 04:21 PM
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here I am again about to do the clutch and replace the transmission fluid. again, all i can find is gl5. I just got done checking napa, autozone and advanced stores in 2 cities and cannot find gl5. Has anyone had problems with the metals being eaten away by gl5 oils?
07-25-2010, 09:05 PM
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07-26-2010, 06:32 AM
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How long have you been running Gl-5 in your transmission? I would go to the dealer, but I just bought 2 seals for about $55 (transmission seal and the rear main seal) and don't feel like getting screwed over on the price again. Maybe once the funds aren't so tight I'd go to the dealer for the GL-4.
Also, what's the difference between the slip and limited slip fluids? Which one would be required when using GL-5 oils?
Last edited by DupermanDave; 07-26-2010 at 06:40 AM.
07-26-2010, 08:55 AM
#18
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Sorry, I cannot find GL-4. I typed that on my phone and guess I typed it out wrong.
How long have you been running Gl-5 in your transmission? I would go to the dealer, but I just bought 2 seals for about $55 (transmission seal and the rear main seal) and don't feel like getting screwed over on the price again. Maybe once the funds aren't so tight I'd go to the dealer for the GL-4.
Also, what's the difference between the slip and limited slip fluids? Which one would be required when using GL-5 oils?
How long have you been running Gl-5 in your transmission? I would go to the dealer, but I just bought 2 seals for about $55 (transmission seal and the rear main seal) and don't feel like getting screwed over on the price again. Maybe once the funds aren't so tight I'd go to the dealer for the GL-4.
Also, what's the difference between the slip and limited slip fluids? Which one would be required when using GL-5 oils?
I used to run mobile1 syn 75/90 GL5.. I was having syncro issues and actually ended up changing the clutch due to it. Switched to GL4 at the same time. Only ran that for about 15K miles. It seemed to me like that GL4 was too thin and wouldn't stick to the gears. Btw, I've found the same gl4 at my local napa. Just can't find it at the more convienant autozone. Then, about 6k miles ago I switched back to a GL5 synthetic and the syncros seem like they like this Valvoline 75/90 Gl5 stuff. I was having issues with similar spec mobile 1 stuff
Check out redlin Mt90, or the amsoil manual trans stuff.
Not to sure what you mean by slip and limited slip.. But it sounds like your referencing stuff that's for a limited slip rear end. Probably wouldn't be best in your transmission
07-26-2010, 09:29 AM
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The gl5 is backwards compatible with GL4. Though, alot of these Toyota transmissions are very picky (as you may know.)
I used to run mobile1 syn 75/90 GL5.. I was having syncro issues and actually ended up changing the clutch due to it. Switched to GL4 at the same time. Only ran that for about 15K miles. It seemed to me like that GL4 was too thin and wouldn't stick to the gears. Btw, I've found the same gl4 at my local napa. Just can't find it at the more convienant autozone. Then, about 6k miles ago I switched back to a GL5 synthetic and the syncros seem like they like this Valvoline 75/90 Gl5 stuff. I was having issues with similar spec mobile 1 stuff
Check out redlin Mt90, or the amsoil manual trans stuff.
Not to sure what you mean by slip and limited slip.. But it sounds like your referencing stuff that's for a limited slip rear end. Probably wouldn't be best in your transmission
I used to run mobile1 syn 75/90 GL5.. I was having syncro issues and actually ended up changing the clutch due to it. Switched to GL4 at the same time. Only ran that for about 15K miles. It seemed to me like that GL4 was too thin and wouldn't stick to the gears. Btw, I've found the same gl4 at my local napa. Just can't find it at the more convienant autozone. Then, about 6k miles ago I switched back to a GL5 synthetic and the syncros seem like they like this Valvoline 75/90 Gl5 stuff. I was having issues with similar spec mobile 1 stuff
Check out redlin Mt90, or the amsoil manual trans stuff.
Not to sure what you mean by slip and limited slip.. But it sounds like your referencing stuff that's for a limited slip rear end. Probably wouldn't be best in your transmission
I may just go ahead and order some redline MT-90 from Amazon, but I'm going to check one more local dealer.
Are the W56 transmissions Gl-5 rates? According to 4crawler's website, they are: "You want to avoid running a GL5 oil in the transmission. The EP additives in a GL5 oil can attack the brass synchro rings on transmissions not rated for GL5 oil (the Toyota transmissions are rated GL4/GL5) and they can make the oil too slippery for proper synchro operation (shifting will feel sluggish - and this does apply to Toyota transmissions). " http://www.4crawler.com/4x4/index.sh...ntheticGearOil
Last edited by DupermanDave; 07-26-2010 at 09:37 AM.
