Punto mk2 gear oil query

[gadge]

I've been thinking of doing a box oil change on my punto mk2 (8V) seen as though it's on 101000 miles and I'm certain it's never had one so I've been doing some research on it but hit a snag. The hand book - and the Haynes manual - states I need to use 1.7 litres of 75w80 synthetic based oil with a GL5 specification. So with that I hit the Internet to find a some and can't seem to find any that match the exact spec that's recommended. I can find plenty of 75w80 fully synth or 75w80 semi sythetic but with only a GL4 spec but none to semi synth with a GL5 spec. Even the TUTELA brand which Fiat recommends is fully synth.

I'm not good on oil knowledge so my question (or should I say questions!) are:

What is GL mean and can I use a GL4 in a gearbox that requires a GL5?

Does it have to be semi synthetic or can I go fully synthetic?

Any advice will be very great fully received

 

[judderbar]

I've been thinking of doing a box oil change on my punto mk2 (8V) seen as though it's on 101000 miles and I'm certain it's never had one so I've been doing some research on it but hit a snag. The hand book - and the Haynes manual - states I need to use 1.7 litres of 75w80 synthetic based oil with a GL5 specification. So with that I hit the Internet to find a some and can't seem to find any that match the exact spec that's recommended. I can find plenty of 75w80 fully synth or 75w80 semi sythetic but with only a GL4 spec but none to semi synth with a GL5 spec. Even the TUTELA brand which Fiat recommends is fully synth.

I'm not good on oil knowledge so my question (or should I say questions!) are:

What is GL mean and can I use a GL4 in a gearbox that requires a GL5?

Does it have to be semi synthetic or can I go fully synthetic?

Any advice will be very great fully received

I have seen a few you tube gearbox experts saying the recommendation to use GL5 in cars with yellow metal synchromesh parts like the punto was due to the composition of the earlier Gl4 products. My local reputable motor factor recommends their own Gl4 oil for the punto but it is too thick and makes for a stiff change.


I am intending to use Total Gear 8 75W/80 GL4+ when I get around to changing the oil.

 

[gadge]

I have seen a few you tube gearbox experts saying the recommendation to use GL5 in cars with yellow metal synchromesh parts like the punto was due to the composition of the earlier Gl4 products. My local reputable motor factor recommends their own Gl4 oil for the punto but it is too thick and makes for a stiff change.


I am intending to use Total Gear 8 75W/80 GL4+ when I get around to changing the oil.

So a GL5 grade is essential then. Well that makes my choice a lot easier I'll go for a fully synth GL5 then

 

[Pugglt Auld Jock]

The simple answer is, use Petronas Tutela 75w80 which is to API GL4-plus. You can buy it at a reasonable price from S4p. It's what Fiat recommend. I'm running both our 2010 1.2 8 valve Panda and my boy's 2012 (mk2) Punto 1.4 8 valve on it with excellent results.

So, what's all the rest of it about? Well, API is the American Petroleum Institute who have been testing and accrediting oils for as long as I can remember. The, slightly, newer "kid on the block" is the ACEA Association des Constructeurs Europeens d'Automobiles. Whose specs are actually more relevant to European operation, but the API has been around and is so well known by us all that it still commands great respect.

The GL stands, very simply, for Gear Lubricant as far as I know? and the number refers to the particular "brew" This is actually the most important part of the whole thing. It used to be that if you put a GL5 into a box that needed a GL4 you were almost certainly going to quickly regret it as the additives in the GL5 would slowly dissolve the softer "yellow" metals in the gearbox!! Very quickly you would have crashing gears as the synchro rings wore out and it affected selector forks and bronze bushings etc, etc, too. I believe this was such a problem that some of the big names have now changed their formulations to stop this happening but who knows who has and who hasn't? there's also old stock around which might catch you out so I wouldn't risk it myself.

The 75w80 is the viscosity (thickness) in this case it behaves like a 75 weight oil when cold and an 80 weight oil when that 80 weight oil is hot. - Think about that for a minute if you like, it's slightly subtle.

The GL4 - Plus is a bit weird though. API don't seem to list it - they go from GL4 to GL5. My best guess, and I'm not alone in this, is that it's an oil which has some of the anti friction and other advantages of a GL5 oil but without the yellow metal "eating" disadvantages? Petronas seem to be the only one I've yet found quoting this actual spec. Maybe a wee bit of a marketing ploy to comply with Fiat's exact spec?

You ask if you can use a GL4 in a box for which a GL5 is specified. Well, i suppose it's not going to "eat" the soft metal internals but I wouldn't, and I definitely wouldn't do it the other way round. ie a GL5 in a GL4 specific box.

Lubricants now a days are very finely honed products with very specific applications. In the past I've found using an incorrect spec of oil in a gearbox, even if you've got the GL spec correct, can make for less than perfect gear change action consequently I'm only really happy if I can get EXACTLY the spec the manufacturer calls for (for our 8valve Punto and Panda's that's API GL4 75w-80.) Doesn't need to be Petronas manufactured - although I think they are currently the only supplier of this GL4-plus "stuff" but if Shell or BP or Castrol or Comma or pretty much anyone else I trust starts putting API GL4-plus on the tin I would be happy to use it. Oh, synthetic vs semi synthetic? Well, pretty much everything on the shelves in my local factor is now synthetic. I think the synthetic product is preferable for many reasons but a big one is that it will almost certainly stay "in spec" for longer.

There are others on this forum Schumi? who know a great deal more about the technicalities of lubricants and maybe one of them will pick up on this and take us further (or tell me I'm speaking a load of absolute twaddle!)

A very involving subject so good luck. There are some interesting sites if you want to know more "Oilem" "Bob is the oil guy" and others, well worth a few minutes of your time.
Regards
Jock

 

[Pugglt Auld Jock]

So a GL5 grade is essential then. Well that makes my choice a lot easier I'll go for a fully synth GL5 then

No, no, no! It's the GL5 which did the damage to boxes, like ours, which need GL4, as your supplier rightly says. What's probably wrong with the stuff he's giving you is it sounds likely, from your description, that it's too thick. I don't know but maybe it's a 75w-90 or 80w-90 (which are common grades). The lower the number the thinner the oil so a 75 is a LOT thinner than a 90 and the thicker oil will make it difficult to get into gear especially in 1st and 2nd and especially when cold.

By the way, just looked in my Haynes and it specifies 75w-80 GL4 (that's GL4 NOT GL5)

PS sorry, It was judderbar who said their factor's oil was too thick. I can assure you the Tutela Technyx https://www.shop4parts.co.uk/?name=..._Panda_III_(09_to_12)_1.2_8v_Transmission_Oil Works just fine

 

[gadge]

No, no, no! It's the GL5 which did the damage to boxes, like ours, which need GL4, as your supplier rightly says. What's probably wrong with the stuff he's giving you is it sounds likely, from your description, that it's too thick. I don't know but maybe it's a 75w-90 or 80w-90 (which are common grades). The lower the number the thinner the oil so a 75 is a LOT thinner than a 90 and the thicker oil will make it difficult to get into gear especially in 1st and 2nd and especially when cold.

By the way, just looked in my Haynes and it specifies 75w-80 GL4 (that's GL4 NOT GL5)

PS sorry, It was judderbar who said their factor's oil was too thick. I can assure you the Tutela Technyx https://www.shop4parts.co.uk/?name=..._Panda_III_(09_to_12)_1.2_8v_Transmission_Oil Works just fine

Great stuff now I'm getting somewhere. I will say though that it's the officail fiat hand book that is telling me to use GL5 and I'm sure my version of Haynes says the exact same thing. The tutella stuff is very close to what that said hand book recommended with the exception that it's fully synthetic not semi synthetic but given that the handbook was written in the early 2000s then maybe gear oil technology has moved on.

 

[Pugglt Auld Jock]

Just turned up a recommendation for Tutela Gearforce which is a later recommendation for these gearboxes. It's still a GL4 but it's a straight 75 weight viscosity so even thinner than the 75w-80. Probably it'll give very slick gearchanging, especially on very cold winter mornings, but I'm "old school" and prefer the idea of an oil with a little bit of "body" to it.

My almost new SEAT IBIZA runs a straight 75 weight oil in it's gearbox and I never have the slightest sign of any baulking even on the coldest of days whereas my 20 year old Cordoba, which ran a thicker "traditional" oil, was always quite reluctant to go into 1st on cold mornings. About 5 years before he (TONY he was called) bit the dust I did a gearbox oil change using the newer transmission fluid (They didn't call it gear oil any more) recommended as an "upgrade" for him. I was very dubious about it because it looked like water compared to what I drained out! Boy was it THIN! But the gear changing was wonderfully light and she did at least another 30'000 miles with that oil in and nothing bad happened. The only effect I noticed was a very slight whine which wasn't there before, especially in 3rd and there was a small amount of gear "rattle" at tick over. The other thing I noticed was a very small clunk - you had to have an ear for it - when selecting gears which I think was the synchro picking up the gear as you were exerting force on it and using up the backlash which you were hearing because of the thinness of the oil. My new Ibiza does it too - I'd love to put some of the older thicker oil in it just to see if the noise went away but I won't because there are a lot more things to consider like oil starvation to bushes and synchro function etc, etc, if you put a thicker oil in.

 

[Pugglt Auld Jock]

Great stuff now I'm getting somewhere. I will say though that it's the officail fiat hand book that is telling me to use GL5 and I'm sure my version of Haynes says the exact same thing. The tutella stuff is very close to what that said hand book recommended with the exception that it's fully synthetic not semi synthetic but given that the handbook was written in the early 2000s then maybe gear oil technology has moved on.

Just checked back with the S4p catalogue and it is indeed the Gearforce (straight 75 weight to GL4) recommended by them for your year! Probably for my boy's Punto too? Although I just double checked the Haynes and it's Technyx for them (75w-80 to GL4- plus) I guess the only significant difference compared with the Technyx is it's thinner - which is what everyone is doing now to reduce drag and up the fuel economy to say nothing of the "holy grail" of reduced emissions!

Now I'm getting to the outer limits of my knowledge but it may well be that the specific GL5 oil recommended by FIAT is one of the "safe" GL5s, or maybe they've changed some of the metals used in the box? From what I've read there do seem to be advantages in terms of wear protection etc with the GL5 spec so if you can rid it of it's voratious appetite for "yellow, soft" metals then there would seem to be advantages to be had. However as GL4 has run very happily in the Panda for nearly 70'000 miles and the Punto for coming up on 50'000 I think I'll just stick with what I know!
Good luck
kind regards
Jock

 

[Pugglt Auld Jock]

Oh, hang on fella, Mk2 you say? what year is that? I've been thinking about my son's 2012 Punto which was the model that came in after the EVO. Mark 2? are we talking here about a car produced before the Punto Grande? If so I doubt if GL5 would even have been around when it was rolling out the showroom!

Here's a pretty definitive paper on the subject in almost understandable language, If you've got the time and inclination to read it! Well worth it if you're interested though.
https://www.widman.biz/uploads/Transaxle_oil.pdf

Ps. It's worth remembering whilst reading that the paper is for the Corvair Club so makes reference to these cars but there's loads of more generaly useful info for the likes of us - at the end of the day though you need to be guided by the manufacturer's full spec for the oil you need.

 

[gadge]

Oh, hang on fella, Mk2 you say? what year is that? I've been thinking about my son's 2012 Punto which was the model that came in after the EVO. Mark 2? are we talking here about a car produced before the Punto Grande? If so I doubt if GL5 would even have been around when it was rolling out the showroom!

Here's a pretty definitive paper on the subject in almost understandable language, If you've got the time and inclination to read it! Well worth it if you're interested though.
https://www.widman.biz/uploads/Transaxle_oil.pdf

Ps. It's worth remembering whilst reading that the paper is for the Corvair Club so makes reference to these cars but there's loads of more generaly useful info for the likes of us - at the end of the day though you need to be guided by the manufacturer's full spec for the oil you need.

Great I'll give that a read through However we're definatley not talking the same bananas here on the car version. The MK2 was the second model made by Fiat between 99-06 and to made it even more confusing there were two versions - MK2 and the MK2b which was a face lifted model with a few more engines. My car is a 2003 pre face lifted MK2 with the evergreen 8V FIRE engine.

As for the GL rating I have no knowledge on when or how long ago they were introduced I'm only saying GL5 as that's what the Fiat punto handbooks tells me to put in (see below)



Strange thing is that the recommended brand (tutela ZC75) that's available today is fully synth and is a GL4 plus so seen as though I'm having trouble finding the exact spec I'm leaning towards perhaps a 75w80 oil (of which there is plenty about) with a GL5 rating (of which there's NOT so many about).

 

[Eklipze3k]

For Jock

 

[judderbar]

oops. So Jock and bob the oil man have told me I got the direction of corrosion potential reversed by favouring GLF. GL5 being worse than GL4. The mk2b punto does specify GL5 though. Presumably GL5 is being specified because of the extreme pressure requirements of the differential.


Even so I will change to total gear 8 and see what happens.

 

[Pugglt Auld Jock]

For Jock
View attachment 204081

Thanks Eklipze. I always thought the Mk 2B - as I now know it to be! - was the best looking. In fact when I was looking for a replacement for our old Panda Parade I nearly bought one but Mrs J really really wanted another Panda. So, of course, we bought a Panda.

 

[Pugglt Auld Jock]

oops. So Jock and bob the oil man have told me I got the direction of corrosion potential reversed by favouring GLF. GL5 being worse than GL4. The mk2b punto does specify GL5 though. Presumably GL5 is being specified because of the extreme pressure requirements of the differential.


Even so I will change to total gear 8 and see what happens.

Hello judderbar. I've been "off the grid" on holiday but now I'm home so catching up on the forum. The difference between a 75w-80 and a straight 75 weight oil is going to be almost negligible in terms of viscosity and you will be avoiding the possibility of damage to any yellow metals by using the GL4 spec. So, in the short term, this is the "sensible" choice (especially as this grade is used in so many other Panda/Punto models with similar boxes?)

However, Just to throw a "spanner" in the works I just came across this: https://www.shop4parts.co.uk/?name=store&op=Details&ProdID=72&sku=25170
Looking on Petronas own site it confirms that it's a GL5. Looks like the info you found in your manual is correct? None of which invalidates the historic cautions about GL5 and yellow metals, but it would seem that your box is compatible with the GL5 - Wonder why our, later model, Pandas take the GL4?