Technical Gearbox oil change

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Technical Gearbox oil change

Alpine26

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I'm thinking of doing a gearbox oil change, I have worked out where the drain and filler plugs are.

I understand the car has to be level to refill.

Is it possible to refill without having to lift the car up? I guess that could be difficult.

If I have to lift the car up but get it level, how do I best do that? I have a set of ramps, a trolly jack and 2 stands but I think I'd be a bit nervous about lifting it level. Can anyone give any advice?
 
Ideally it should be level, but if the front wheels are on the ramps, the slight slope will not make a huge difference to the oil level inside, It will cause you to add a little extra, but not enough to do any harm.

When raising it, or working underneath, always have someone else nearby, in case of problems. If nothing else, they can call for help.

Always consider where it will go if it moves, and have space there, and keep yourself out of that space.

To get it level, put the front wheels on the ramps. Put it in 1st gear to help prevent the front wheels turning. Apply the handbrake.
Now raise the rear, trolley jack under the centre of the rear axle beam. Do this slowly, and apply forward pressure to keep the car on the ramps, as the trolley jack will tend to pull the car towards you. When high enough, place the stands under it.

The surface you are working on needs to be level.
Keep space behind, enough for the car if it rolls off the stands, the gear and handbrake will stop it.
If it rolls while jacking, release the jack to get the rear wheels back on the ground.
Filling with oil really needs a big syringe and pipe. It will get messy.
 
As long as your car isn't lowered too much, it's simple to refill with it on the ground.

I just used a funnel with some garden hose on the bottom. I can stick it in the filler hole and top up from the engine bay. Once the oil starts to trickle out the filler hole, your are done.
 
many thanks for the replies guys

Can I just check I have located the correct plugs. I think the filler plug is a 12mm hex front of the engine facing forwards, and the drain is an 8mm at the lowest point in the centre of the car, is that right?

I think if I lift the car to undo the plugs, I can then lower it and then refill from above using a section of hose I have, as suggested.

Is it full when the filler plug overflows?

What oil should I use? The handbook refers to 80/90 non-EP, but also 80 EP. And what quantity?

My car has had a new clutch just before I bought it, so would a gearbox oil change had to be done as part of that, or not necessarily?

Sorry in advance about all the question!
 
gearbox oil is rarely changed in the UK, don't know why but I'd be amazed if the oil in there isnt factory.

And yes, lift car, undo the fill plug first cause you don't want to drain it and then not be able to get it out. Then drain, refit drain plug. Drop car down and as above get a pipe that fits in the fill hole, stick a funnel on end and slowly fill until it just start coming out the fill hole, refit fill plug. done.

I use this stuff normally, is what fiat use. https://www.shop4parts.co.uk/?name=store&op=Product&ProdID=72
 
gearbox oil is rarely changed in the UK, don't know why but I'd be amazed if the oil in there isnt factory.

And yes, lift car, undo the fill plug first cause you don't want to drain it and then not be able to get it out. Then drain, refit drain plug. Drop car down and as above get a pipe that fits in the fill hole, stick a funnel on end and slowly fill until it just start coming out the fill hole, refit fill plug. done.

I use this stuff normally, is what fiat use. https://www.shop4parts.co.uk/?name=store&op=Product&ProdID=72
blu's pretty much got it covered here. I'm very particular about lubricants and in particular what I put in transmissions - almost exclusively I'll use the manufacturer's recommended product - which is what S4p will sell you (see blu's post above). I also agree with his puzzlement about why we don't change transmission oils on a regular basis (I try to do our family vehicles around every 50,000 miles). There's a lot about lubricants on the forum but, in particular relating to transmission oils if it specifies an API GL4 oil don't even think about putting a GL5 in it!

It's not unusual to renew or partially renew gearbox oil when the clutch is done as some will have been lost when/if a drive shaft is pulled. The question then becomes what did they put back in? Probably something compatible - but who can say? It doesn't take much to completely renew it so why wouldn't you?

When I'm doing this, as my drive slopes gently down to the roadside, I reverse it onto the drive and, with the hand brake firmly applied, I chock the back wheels. Then I jack the front up until putting a spirit level on the sills shows the car to be level (I don't get too anal about being exactly level) and put axle stands on both sides at the front - it's going nowhere now and the front is just at a very comfortable height for me to wriggle under. I wouldn't be doing this on anything more than a slight slope like mine as I would be worried it might move.

For years I've struggled with "squeezy" oil bottles, lengths of pipe and funnels (which actually works quite well, but dribbles a bit and can get fiddly to judge when to stop pouring so as not to waste oil) then I saw this: https://www.machinemart.co.uk/p/cgg...l8wolKiLt0nYH7PLrOqCf1jHCgdXtO9hoCAiQQAvD_BwE which I bought in one of their VAT free events and I've never looked back. You can use it to suck the old oil out too but I prefer to pull the drain plug to let any solids in the bottom of the box come out with the oil. I also like to get it good and hot, so probably a 10 mile trip or so (put a hand on the casing to see how hot it is) Doing this will make the oil much thinner and tend to "stir" up any solids so they will be in suspension in the oil when you pull that plug. Oh, by the way, check you can get the filler plug out before you pull the drain plug won't you!

As I'm not too familiar with your model's rear axle I looked it up and found this: https://www.b-parts.com/en/store/pr...84hq2Um9-112AtQfxTFORiimjiAAnAyRoCq74QAvD_BwE If yours is like this I think it will be robust enough to do as PB advises by jacking in the middle of the axle. However - sorry PB - I'm not a fan of jacking in the middle of axles generally and especially not in the middle of torsion beams like those used on many modern vehicles. If they bend, even by quite a small amount you'll wish you hadn't. I prefer to jack on a chassis box section - with a piece of wood to spread the load and stop slipping - or suspension mounting point.
 
Just a thought. Why are you considering a gearbox oil change? Is there an issue that you think might be fixed by this? As said above, the oil is probably original, so a change will be beneficial, but almost certainly will not fix anything that is not working properly now.

If you have gear selection problems, these are most likely to be the clutch on its way out. A heavy to operate clutch is a symptom of this. The cables get a hard time, and are a little tricky to change due to the RHD dash restricting access.
 
For years I've struggled with "squeezy" oil bottles, lengths of pipe and funnels (which actually works quite well, but dribbles a bit and can get fiddly to judge when to stop pouring so as not to waste oil) then I saw this: https://www.machinemart.co.uk/p/cgg...l8wolKiLt0nYH7PLrOqCf1jHCgdXtO9hoCAiQQAvD_BwE which I bought in one of their VAT free events and I've never looked back. You can use it to suck the old oil out too but I prefer to pull the drain plug to let any solids in the bottom of the box come out with the oil. I also like to get it good and hot, so probably a 10 mile trip or so (put a hand on the casing to see how hot it is) Doing this will make the oil much thinner and tend to "stir" up any solids so they will be in suspension in the oil when you pull that plug. Oh, by the way, check you can get the filler plug out before you pull the drain plug won't you!

Been meaning to buy something like that for at least 15 years but never got around to lol.
Actually, on these gearboxes though, i've found your common garden hose is the perfect size pipe to fit in the fill hole. I then run that up and cable tie it to the bar that holds the bonnet up. Steal a funnel of the wife from the kitchen, they seem to fit in a garden hose perfect lol.
Then its a matter of checking how much oil should go in from empty so you know when to stop just pouring.
Takes a while as the stuff is so thick but you don't have to hold anything up so you can even just do other stuff while it fills (y)
 
Back in the seventies and eighties, gear oil bottles sometimes came with a double ended spout in the cap, with a tube to the bottom of the bottle as well as the one out the top. Bottle can be kept upright, adn when squeezed, will push oil up the tube.

I still have one, not split yet, which happily tops up gearboxes and rear axles when necessary. (Rear axle, Suzuki Carry van, belongs to a friend. Must be due another service.)
 
my handbook says I should use Tutela zc 80/s but I understand it is no longer produced.

Will this suffice (although its 75W): https://www.morrislubricants.co.uk/products/auto/gear-transmission-oils/lodexol-mtf-75w-90.html

can anyone confirm what quantity I will need?

Some gearboxes use EP additives, some don't. Putting in the wrong stuff can lead to poorer gearhange quality. The Morris stuff may well be fine, but actual additive package is difficult to determine.
See post #5 and the link to Shop4Parts, that's genuiine Fiat stuff, so no problem with the formula. Don't go looking for better prices, any oil is cheaper than a gearbox.
2 litres should be enough. Box takes around 1.5 I think.
 
Some gearboxes use EP additives, some don't. Putting in the wrong stuff can lead to poorer gearhange quality. The Morris stuff may well be fine, but actual additive package is difficult to determine.
See post #5 and the link to Shop4Parts, that's genuiine Fiat stuff, so no problem with the formula. Don't go looking for better prices, any oil is cheaper than a gearbox.
2 litres should be enough. Box takes around 1.5 I think.

Thanks Bill, but the Shop4Parts link above to Tutela is GL5 spec, https://extranetpli-eu.pli-petronas.com/dsp/pdf/eng/scat/1475_scat_eng.pdf but my handbook says I need GL4

I understand getting the wrong GL can cause damage too. Pretty complicated stuff, oil! The Morris is GL4.
 
Thanks Bill, but the Shop4Parts link above to Tutela is GL5 spec, https://extranetpli-eu.pli-petronas.com/dsp/pdf/eng/scat/1475_scat_eng.pdf but my handbook says I need GL4

I understand getting the wrong GL can cause damage too. Pretty complicated stuff, oil! The Morris is GL4.
Almost anything mechanical, and especially if it's to do with IC engines, interests me but I've always had a special interest in tyres (I suppose due to my earlier employment) and over the last decade I've become more and more interested in lubricants. So I'm always looking for info and articles on that subject. Opie Oils is a highly respected supplier/specialist and they have this article on their website which you might like to read: https://www.opieoils.co.uk/t-api-car-gear-oil-specifications-explained.aspx Right at the bottom there is a small reference to the GL4 vs GL5 problem.

Some years ago, when GL5 first appeared on the scene, there were reports of it causing damage to the soft metals, some call them "yellow" metals, in gearboxes (so brass and phosphor bronze typically used in bushings and synchro rings). I've read a lot about the problem and if you want to go into it in much greater detail without getting too ridiculously technical this article explains it all quite eloquently: https://www.widman.biz/uploads/Transaxle_oil.pdf Although it refers to the Corvair (a vehicle which interests me greatly which is how I came across it) the problem caused by the oil would be applicable to any vehicle.

Today though there are anomalies. Some (possibly many) of the manufacturers claim their GL5 is now completely compatible with older boxes which needed GL4 but I've been unable to find anything definitive as to why and then there is a "rogue" spec, not quoted in any official API list I've seen, of API GL4+

In fact the Tutella Technyx https://www.shop4parts.co.uk/?name=..._Panda_III_(09_to_12)_1.2_8v_Transmission_Oil which I use in my Panda and my boy's Punto is rated GL4+ So, personally, I always use the actual oil recommended by the manufacturer. I think if you go by Shop4parts recommendation for your vehicle you won't go far wrong and if you're feeling unsure please do just give them a ring. They are very helpful and approachable people (who all seem to be called Mike or Mick!) I've rung them a few times to sort something out which wasn't listed on their website - they seem to stock, or are able to get, a lot more than they list on line - and they've always been extremely anxious to help.

Finally though I would say, that unless I had very strong evidence to the contrary, I would not be putting a GL5 oil in a box for which the manufacturer's original recommendation was for a GL4. - But then I'm a confirmed "feardie"!
 
I have tried on numerous occasions to get my head around all the different acronyms, grades, API numbers etc etc with oils and it is a minefield of information. Pretty hard to get your head around it all and for that reason i tend to stick to the exact recommended oils (which in itself can be a challenge if the car and as such the manual is really old and never been updated).

And lets not forget manuals arent always even right... is it the gearbox oil capacity thats wrong in the haynes for a cinq? one of them is wrong and always has been and was never revised.
 
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I have tried on numerous occasions to get my head around all the different acronyms, grades, API numbers etc etc with oils and it is a minefield of information. Pretty hard to get your head around it all and for that reason i tend to stick to the exact recommended oils (which in itself can be a challenge if the car and as such the manual is really old and never been updated).

And lets not forget manuals arent always even right... is it the gearbox oil capacity thats wrong in the haynes for a cinq? one of them is wrong and always has been and was never revised.

So much worse now a days too - Oh for the days when it was an EP80 in the gearbox and then you had to check if the back axle was a 90 or 140! If in doubt give Opie a ring. Really helpful and knowledgeable people.

Many years ago I helped a couple of friends, one with a Mirafiore and one with a wee 500. There was a 128 too, but that's another story. I don't remember what any of their capacities were. Since then there's been a succession of Pandas and my boy's Punto for me to play with. To the best of my recollection a couple of litres does the job with a little to spare in case you spill some. Fortunately both our current cars '10 plate Panda 1.2 and '12 plate Punto 1.4 take the Technyx which is very convenient.
 
most my fluids tend to come from opie actually. Not always but great service, decent prices. They even sent me another bottle of coolant once when a courier delivered to the wrong house cause they said it'll be quicker than waiting for them to sort it. Can't complain about them at all (y)
 
Having looked into this further, there is a further complication which is that the correct specification oil for my car should be a mineral based oil. Some of the oils I have been looking at are synthetic or semi-synthetic, which I suspect is suitable for more modern cars.

This is the best matched spec I can find, and it also refers to MIL-L-2105 which is quoted in my handbook https://www.mpmoil.co.uk/products/11000/gearbox-oil-sae-80w-gl-4-mineral

Euro Car Parts sell it. I've just ordered some online and with a weekend discount code its £6 for 1 litre
 
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