Will do. Not sure how useful it will be to save this "used" gear 300, but I have a friend with an Alfa where it could be put !
Motul gear 300
- Thread starter Popsy
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I imagine it can't be that old....just filtrate the oil through gaze and you're good.
I didn't realize this is rear wheel drive and the fluid of the transaxle is mixed with the differential correct. In that case I would use a "GL-4/5" fluid with MT-1 specs...this way you get the extra additives for the diff but the buffering adds for the synchronizers in the transmission.
It's FWD. Transaxle literally means transmission on the axle in same casing as diff. All modern cars feature this architecture no matter FWD or RWD.
People get confused with the name because in the old days when transaxle first started in high end cars like Alfa most others had traditional setup with gearbox in front and diff at back.
Modern FWD cars didn't exist back then.
People get confused with the name because in the old days when transaxle first started in high end cars like Alfa most others had traditional setup with gearbox in front and diff at back.
Modern FWD cars didn't exist back then.
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For some reason I recalled that the Barchetta was RWD....
we never had this model or any FIAT product made from the mid 80s onwards until the return of the new 500 a few years ago.
Most modern FWD cars call for the use of GL-4 spec fluids today and for the past several decades, not that there aren't some exceptions but for the best health for the fragile synchronizers GL-4 only is the best application.
we never had this model or any FIAT product made from the mid 80s onwards until the return of the new 500 a few years ago.
Most modern FWD cars call for the use of GL-4 spec fluids today and for the past several decades, not that there aren't some exceptions but for the best health for the fragile synchronizers GL-4 only is the best application.
Barchetta was a FWD, but nonetheless a good handling car. It was featured in TGs Three Wise Men episode.
Regarding FWD and GL4 oils, I guess it depends upon perspective. You are based in NA so most of your contact with cars are of domestic or Asian. Asian FWD cars are weak and torque less when compared with European cars. Friends 09 Civic Type R is as fast as a VW diesel or Renault diesel on steel wheels. With half the torque.
Most Euro use GL4+ these days.
Regarding FWD and GL4 oils, I guess it depends upon perspective. You are based in NA so most of your contact with cars are of domestic or Asian. Asian FWD cars are weak and torque less when compared with European cars. Friends 09 Civic Type R is as fast as a VW diesel or Renault diesel on steel wheels. With half the torque.
Most Euro use GL4+ these days.
Originally Posted By: chrisri
Barchetta was a FWD, but nonetheless a good handling car. It was featured in TGs Three Wise Men episode.
Regarding FWD and GL4 oils, I guess it depends upon perspective. You are based in NA so most of your contact with cars are of domestic or Asian. Asian FWD cars are weak and torque less when compared with European cars. Friends 09 Civic Type R is as fast as a VW diesel or Renault diesel on steel wheels. With half the torque.
Most Euro use GL4+ these days.
Good observations chrisri.
Technically there should be NO issue using GL-4+ or GL-4/5 in any typical FWD manual transmission car that have spec'd the GL-4 only product, they are supposed to have enough protective buffering additives in them that they should not cause any harm to yellow metals in the synchronizers. I believe that those products also meet MT-1 specs as well, which again indicates that they are totally safe for any synchronized manual gearbox and will not damage those yellow metals.
The problem is mostly likely me, I'm still not totally convinced that those products will provide the best shift quality and protection for those car gearboxes. Do I have documented proof for my concerns? No.
Barchetta was a FWD, but nonetheless a good handling car. It was featured in TGs Three Wise Men episode.
Regarding FWD and GL4 oils, I guess it depends upon perspective. You are based in NA so most of your contact with cars are of domestic or Asian. Asian FWD cars are weak and torque less when compared with European cars. Friends 09 Civic Type R is as fast as a VW diesel or Renault diesel on steel wheels. With half the torque.
Most Euro use GL4+ these days.
Good observations chrisri.
Technically there should be NO issue using GL-4+ or GL-4/5 in any typical FWD manual transmission car that have spec'd the GL-4 only product, they are supposed to have enough protective buffering additives in them that they should not cause any harm to yellow metals in the synchronizers. I believe that those products also meet MT-1 specs as well, which again indicates that they are totally safe for any synchronized manual gearbox and will not damage those yellow metals.
The problem is mostly likely me, I'm still not totally convinced that those products will provide the best shift quality and protection for those car gearboxes. Do I have documented proof for my concerns? No.
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Originally Posted By: chrisri
Popsy, you are right, FIAT changed specification on those gearboxes few times (C514 as well).
There were some modifications on c510 depending on applications, and linkages are different. Alfa Romeo has more refined ones which is no surprise since they are more expensive cars.
Nonetheless I'm surprised 300V didn't do it's "magic" in your FIAT. It worked well in my AR. Currently I have none of c510, but I have c514 filled with Syntrans Transaxle. Previous fill was ZC75 Synth. I had exactly the same problem with Tutela as your with Motul; very smooth on coldest mornings (4-5*C), but as soon as at temp. very notchi with difficult first gear engaging.
Castrol cured most of the problem, but not all. Way better though, I'm satisfied for a 250k, 17 years old car.
I believe ZC 75 has massive amounts of additives, and it is on the thinner side. Old synchros simply don't work as well as new with these oil.
Most current spec is Car Technyx 75w85, a GL4+ lubricant. DO NOT use plain GL4 if you don't want to see your diff OUTSIDE of your gearbox casing.
Edit; I'm using ZC75 in Getrag in my Stilo. It works brilliant even though it was never specified for GL5 MTF.
You mentioned OP's is a manual transaxle gearbox, which presumably comes with hypoid bevel gears.
It makes perfect sense for a typical manufacturer like Fiat to upgrade from GL4 to GL4+ and/or GL5 that comes with enhanced EP additives for improved components protection ,an oil specs as preferred by hypoid gear application in Europe ....... unlike a typical NA manufacturer.
Besides OP, you too encounter notchy gearbox shift when oil is warm ...... it's baffling ....
Popsy, you are right, FIAT changed specification on those gearboxes few times (C514 as well).
There were some modifications on c510 depending on applications, and linkages are different. Alfa Romeo has more refined ones which is no surprise since they are more expensive cars.
Nonetheless I'm surprised 300V didn't do it's "magic" in your FIAT. It worked well in my AR. Currently I have none of c510, but I have c514 filled with Syntrans Transaxle. Previous fill was ZC75 Synth. I had exactly the same problem with Tutela as your with Motul; very smooth on coldest mornings (4-5*C), but as soon as at temp. very notchi with difficult first gear engaging.
Castrol cured most of the problem, but not all. Way better though, I'm satisfied for a 250k, 17 years old car.
I believe ZC 75 has massive amounts of additives, and it is on the thinner side. Old synchros simply don't work as well as new with these oil.
Most current spec is Car Technyx 75w85, a GL4+ lubricant. DO NOT use plain GL4 if you don't want to see your diff OUTSIDE of your gearbox casing.
Edit; I'm using ZC75 in Getrag in my Stilo. It works brilliant even though it was never specified for GL5 MTF.
You mentioned OP's is a manual transaxle gearbox, which presumably comes with hypoid bevel gears.
It makes perfect sense for a typical manufacturer like Fiat to upgrade from GL4 to GL4+ and/or GL5 that comes with enhanced EP additives for improved components protection ,an oil specs as preferred by hypoid gear application in Europe ....... unlike a typical NA manufacturer.
Besides OP, you too encounter notchy gearbox shift when oil is warm ...... it's baffling ....
GL4+ and GL5 MTF, not gear oil, are yellow metal friendly. Most oils for manual gearboxes that require EP additive are GL4+. Would I used it in a gearbox requiring GL4 fluid?
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
Originally Posted By: chrisri
GL4+ and GL5 MTF, not gear oil, are yellow metal friendly. Most oils for manual gearboxes that require EP additive are GL4+. Would I used it in a gearbox requiring GL4 fluid?
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
I doubt that most shops here know what you have posted above.
I'm pretty well versed on light vehicle manual transmissions, and I didn't realize what you posted either.
Thanks!
GL4+ and GL5 MTF, not gear oil, are yellow metal friendly. Most oils for manual gearboxes that require EP additive are GL4+. Would I used it in a gearbox requiring GL4 fluid?
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
I doubt that most shops here know what you have posted above.
I'm pretty well versed on light vehicle manual transmissions, and I didn't realize what you posted either.
Thanks!
I've always wondered about GL5 being bad for yellow metal, my ECHO has brass synchros (I've seen them with my own eyes) and yet the owner's manual says GL5 is fine - which is what I used for the first 150,000 miles until I tore it apart for a noisy output shaft bearing. They looked fine at that time.
Maybe different types of brass with different alloys react differently.
Maybe different types of brass with different alloys react differently.
Modern GL5 MTF pass yellow metal scuffing test, and provide normal EP protection as GL5 gear oil for differential.
Wear on synchros is higher (slightly) compared to a GL4 or GL4+, but that is not an issue .
Poorer shiftability is, but sometimes manufacturers need to make compromise between keeping diff intact and overall drivability.
A friend of mine rebuild gearboxes for a living, he says nine out of ten faults are either diff graneding or bearings. It seems synchros are strong today.
Wear on synchros is higher (slightly) compared to a GL4 or GL4+, but that is not an issue .
Poorer shiftability is, but sometimes manufacturers need to make compromise between keeping diff intact and overall drivability.
A friend of mine rebuild gearboxes for a living, he says nine out of ten faults are either diff graneding or bearings. It seems synchros are strong today.
Originally Posted By: GiveMeAVowel
Originally Posted By: chrisri
GL4+ and GL5 MTF, not gear oil, are yellow metal friendly. Most oils for manual gearboxes that require EP additive are GL4+. Would I used it in a gearbox requiring GL4 fluid?
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
I doubt that most shops here know what you have posted above.
I'm pretty well versed on light vehicle manual transmissions, and I didn't realize what you posted either.
Thanks!
Including Bitogers ......
At the prospect of being flamed, I had been reading here in Bitog every now so often ..... GL5 corrodes synchronizers manual trans .....then you have Manuals monsters advocating manufacturer knows best in recommending GL4 ...... then there are dogmas that GL4 only for manual trans and GL5 only for differential(where specified) and mutually exclusive etc......
Originally Posted By: chrisri
GL4+ and GL5 MTF, not gear oil, are yellow metal friendly. Most oils for manual gearboxes that require EP additive are GL4+. Would I used it in a gearbox requiring GL4 fluid?
Only if I've put additional strain on the differential by turbocharging, remap, etc.
All other being equal GL4 fluid will always shift better than GL4+ and especially GL5 MTF.
I doubt that most shops here know what you have posted above.
I'm pretty well versed on light vehicle manual transmissions, and I didn't realize what you posted either.
Thanks!
Including Bitogers ......
At the prospect of being flamed, I had been reading here in Bitog every now so often ..... GL5 corrodes synchronizers manual trans .....then you have Manuals monsters advocating manufacturer knows best in recommending GL4 ...... then there are dogmas that GL4 only for manual trans and GL5 only for differential(where specified) and mutually exclusive etc......
I thought GL5 used to have suphur EP additives which were corrosive to brass/yellow metal, but for at least the past 15 years there are now "buffered" additives which are yellow metal safe.
Gear oil with MIL-L-2105 rating are also supposed to pass some copper corrosion tests
http://my.umbc.edu/system/shared/attachm....pdf?1334852745
(correct me but MIL-L-2105D is supposedly GL5 equivalent)
I understood the issue with GL5 and yellow metal could also be that the EP protective layer formed by oil bonds so strongly to the metal so when there is friction it isn't the protective layer formed by additives that strip but some parts of the metal itself => in UOA you can find more copper with a GL5 lubricant than a GL4 (but less iron).
I replaced the gearbox oil in the Marea by Castrol Syntrans transaxle yesterday (only 2 bottles in stock so the Barchetta will wait a bit, I won't be using it), and the oil that I drained looked so dirty I dumped it (even if it was like a month old). Guess Castrol Syntrans GL4 has good cleaning abilities!
The gearbox is less smooth now, and feels slower (so that helps the gearss not to grind !), but the feeling is still very correct so I'm good with it.
Gear oil with MIL-L-2105 rating are also supposed to pass some copper corrosion tests
http://my.umbc.edu/system/shared/attachm....pdf?1334852745
(correct me but MIL-L-2105D is supposedly GL5 equivalent)
I understood the issue with GL5 and yellow metal could also be that the EP protective layer formed by oil bonds so strongly to the metal so when there is friction it isn't the protective layer formed by additives that strip but some parts of the metal itself => in UOA you can find more copper with a GL5 lubricant than a GL4 (but less iron).
I replaced the gearbox oil in the Marea by Castrol Syntrans transaxle yesterday (only 2 bottles in stock so the Barchetta will wait a bit, I won't be using it), and the oil that I drained looked so dirty I dumped it (even if it was like a month old). Guess Castrol Syntrans GL4 has good cleaning abilities!
The gearbox is less smooth now, and feels slower (so that helps the gearss not to grind !), but the feeling is still very correct so I'm good with it.
Originally Posted By: Popsy
I thought GL5 used to have suphur EP additives which were corrosive to brass/yellow metal, but for at least the past 15 years there are now "buffered" additives which are yellow metal safe.
Gear oil with MIL-L-2105 rating are also supposed to pass some copper corrosion tests
http://my.umbc.edu/system/shared/attachm....pdf?1334852745
(correct me but MIL-L-2105D is supposedly GL5 equivalent)
I understood the issue with GL5 and yellow metal could also be that the EP protective layer formed by oil bonds so strongly to the metal so when there is friction it isn't the protective layer formed by additives that strip but some parts of the metal itself => in UOA you can find more copper with a GL5 lubricant than a GL4 (but less iron).
I replaced the gearbox oil in the Marea by Castrol Syntrans transaxle yesterday (only 2 bottles in stock so the Barchetta will wait a bit, I won't be using it), and the oil that I drained looked so dirty I dumped it (even if it was like a month old). Guess Castrol Syntrans GL4 has good cleaning abilities!
The gearbox is less smooth now, and feels slower (so that helps the gearss not to grind !), but the feeling is still very correct so I'm good with it.
Could be that the new Castrol Syntrans additives will eventually be re-bonding with the synchros and some of the smoothness you had will return with more miles.
I thought GL5 used to have suphur EP additives which were corrosive to brass/yellow metal, but for at least the past 15 years there are now "buffered" additives which are yellow metal safe.
Gear oil with MIL-L-2105 rating are also supposed to pass some copper corrosion tests
http://my.umbc.edu/system/shared/attachm....pdf?1334852745
(correct me but MIL-L-2105D is supposedly GL5 equivalent)
I understood the issue with GL5 and yellow metal could also be that the EP protective layer formed by oil bonds so strongly to the metal so when there is friction it isn't the protective layer formed by additives that strip but some parts of the metal itself => in UOA you can find more copper with a GL5 lubricant than a GL4 (but less iron).
I replaced the gearbox oil in the Marea by Castrol Syntrans transaxle yesterday (only 2 bottles in stock so the Barchetta will wait a bit, I won't be using it), and the oil that I drained looked so dirty I dumped it (even if it was like a month old). Guess Castrol Syntrans GL4 has good cleaning abilities!
The gearbox is less smooth now, and feels slower (so that helps the gearss not to grind !), but the feeling is still very correct so I'm good with it.
Could be that the new Castrol Syntrans additives will eventually be re-bonding with the synchros and some of the smoothness you had will return with more miles.
I hope you are right
I haven't had the opportunity to warm up the gearbox on a long trip, maybe that will help the oil to "settle"
I haven't had the opportunity to warm up the gearbox on a long trip, maybe that will help the oil to "settle"
Originally Posted By: Popsy
I hope you are right
I haven't had the opportunity to warm up the gearbox on a long trip, maybe that will help the oil to "settle"
A lot of the advanced additive packs will develop a film which actually bonds with the metal, it could be that the additive packae from the previous gear oil was removed with the syntrans and now will be replaced by its own over a small period of time. Yes, I would think that some heat will help the process.
I hope you are right
I haven't had the opportunity to warm up the gearbox on a long trip, maybe that will help the oil to "settle"
A lot of the advanced additive packs will develop a film which actually bonds with the metal, it could be that the additive packae from the previous gear oil was removed with the syntrans and now will be replaced by its own over a small period of time. Yes, I would think that some heat will help the process.
Originally Posted By: Popsy
Hi there,
Long story short, my car got a "new" (only 217K Km) gearbox, so I have now two cars with Fiat C510 gearboxes.
In one I put some Motul gear 300 75W90 like 2000Km ago, and I am not impressed. When cold everything is ok, no problem shifting, everything is smooth, etc, but when hot, the gearbox is very notchy, difficult to put into any gear, if you are silly enough to push the engine above 4000rpm you can almost say goodbye to do 3-4 or 4-5, and when you are stopped at a red-light, you have to think twice before engaging the first speed.
I admit I am much more delicate with the engine and gearbox when cold, but there's definitely something happening with heat, the longer I travel, the more horrible the gearbox becomes. I am surprised because Motul gear 300 is usually highly regarded, and someone on the forum said he had better luck with gear 300 than OEM liquid (Selenia ZC 75 synth).
The other C510 gearbox is currently filled with Castrol syntrans multivehicles 75W90 and is perfectly smooth, cold or hot.
Should I dump the gear 300 and replace with something else? I'd be a bit disgusted to do that, considering the price of this oil
Yes dump the motul and put the oil with correct viscosity, ZC75 is 75w-80 oil, where motul is 75w-90. Transmission is very particular on viscosity.
Hi there,
Long story short, my car got a "new" (only 217K Km) gearbox, so I have now two cars with Fiat C510 gearboxes.
In one I put some Motul gear 300 75W90 like 2000Km ago, and I am not impressed. When cold everything is ok, no problem shifting, everything is smooth, etc, but when hot, the gearbox is very notchy, difficult to put into any gear, if you are silly enough to push the engine above 4000rpm you can almost say goodbye to do 3-4 or 4-5, and when you are stopped at a red-light, you have to think twice before engaging the first speed.
I admit I am much more delicate with the engine and gearbox when cold, but there's definitely something happening with heat, the longer I travel, the more horrible the gearbox becomes. I am surprised because Motul gear 300 is usually highly regarded, and someone on the forum said he had better luck with gear 300 than OEM liquid (Selenia ZC 75 synth).
The other C510 gearbox is currently filled with Castrol syntrans multivehicles 75W90 and is perfectly smooth, cold or hot.
Should I dump the gear 300 and replace with something else? I'd be a bit disgusted to do that, considering the price of this oil
Yes dump the motul and put the oil with correct viscosity, ZC75 is 75w-80 oil, where motul is 75w-90. Transmission is very particular on viscosity.
A small update, after ~1500Km, Castrol Syntrans transaxle is doing great in the Marea. Shifting is smooth and there's no grinding. I noticed with time (and heat?) I can now shift a bit faster.
All in all I'm very satisfied, for a ~220000Km old gearbox it is still very satisfying (compared with other gearboxes from friend's cars with low mileage)
On the other hand, still waiting for the oil to arrive for the Barchetta...I made the mistake of ordering some 300V to share the shipping costs and it is on back order (my local dealer now only sells Fuchs oil and rusty Mahle filters
)...
All in all I'm very satisfied, for a ~220000Km old gearbox it is still very satisfying (compared with other gearboxes from friend's cars with low mileage)
On the other hand, still waiting for the oil to arrive for the Barchetta...I made the mistake of ordering some 300V to share the shipping costs and it is on back order (my local dealer now only sells Fuchs oil and rusty Mahle filters
After a looong time, finally put Castrol Syntrans Transaxle in the Barchetta (had a minor accident with it, didn't help).
I didn't notice a difference when cold (was already smooth), but it is definitely smoother when hot. We'll see how it evolves with time!
Oh, and Gear 300 I drained wasn't foamy at all (unlike the Mobil oil I put before Motul gear 300).
I didn't notice a difference when cold (was already smooth), but it is definitely smoother when hot. We'll see how it evolves with time!
Oh, and Gear 300 I drained wasn't foamy at all (unlike the Mobil oil I put before Motul gear 300).
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