What Gearbox oil to use?

[begins]

Hi all,

I have a pre-owned C5 (Year 2007).

I'm wondering whether there is an alternative beside using the Esso AL4 gearbox oil.

Any gurus here who have successfully used other ATF with satisfaction?

Kindly advise me and Thank you very much.

Regards,

[CitroJim]

Welcome begins

No, no and thrice no. Look at my signature

No, basically there is no substitute at all for the LT71141 ATF used in the AL4 and 4HP20 'boxes.

This subject has been discussed in intimate detail on here several times but always the conclusion is the same: there is no substitute.

Sorry

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Hi Jim,

Thank you very much for the prompt reply.

I guess I must be trying my luck here. Do you guys add gearbox vitalizer or stop leak liquid to prolong its life span? What is the better way to maintain it? Keep changing AL4 at regular intervals (how frequent)?

Thank you very much.

Regards,

[CitroJim]

Do you guys add gearbox vitalizer or stop leak liquid to prolong its life span?

No, no additives at all, just nice, fresh expensive LT71141 and fairly frequent changes. In the case of a car with no history a couple of changes will be done in quick succession to flush out as much of the old stuff as possible. This is especially important if there is any suggestion that Dexron has been used in the past. Sadly, too many garages think all ATF is the same and if it's red that's OK and it'll do for any automatic... 'Fraid not

I'd say every 15,000 miles is fine once you know you have good, fresh LT71141 in there and maintaining the level very carefully,

For the old-school 'box on my XM it gets a change of ATF when the engine has an oil change.... It's easy and Dexron II is very cheap; sadly two things that don't apply to the AL4 and LT71141 ATF

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Hi Jim,

Is there such thing like a gearbox oil filter that has to be changed as well?

By the way, I find the car jerky when the gearbox shift itself between 1st and 2nd gear other wise it is smooth at higher gear. I'm quite confused here as some said this is how citroen gearbox behaved and some said the gearbox is going to kaput. So which is correct?

Thank you very much for your patience in answering my questions.

Regards,

[CitroJim]

No problem at all. Yes there is a filter but it's internal and to get to it means having the 'box apart. They are 'sealed for life' and strictly never need servicing. Their life is 100,000 miles or ten years. If they reach that then they've met their target.

I'm not skilled on the AL4 but I do believe there are some known problems with the valve block electrovalves, particularly the one that regulates pressure. I'm sure one of our members who is wise on the AL4 will be along to advise soon.

My speciality lies with the AL4's big sister - the 4HP20 used with the V6 engines...

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Hix Jim,

Is there a way to prolong the lifespan of the gearbox? For example, by installing an external ATF cooler?

Thank you.

Regards,

[CitroJim]

For example, by installing an external ATF cooler?

Not easily but that raises, indirectly, a very good point. I'm of a belief that all but one of the blown-up HP20s I've rebuilt failed because of cooling system problems. Rad sealant had been used in at least two cases and that evil stuff appears to block the transmission cooler.

Therefore, knowing these 'boxes run hot I'd say definitely the cooling system should be kept in top condition always. Keep the coolant changed every year, topped up to level and if any distress is evident anywhere in the cooling system then rectify it.

NEVER use any radiator sealant except perhaps Forte Stop Leak which I believe may be safe but even then I'd be cautious.

That and keeping the ATF changed at regular intervals is all you can really do to make sure the 'box lives as long as it possibly can.

[addo]

You can fit a sandwich type oil cooler adapter to most AL4 installations. EG: http://www.ebay.com/itm/360484288546" onclick="window.open(this.href);return false; Then add a seven row stacked plate cooler and flex lines between.

What country are you in? ATF doesn't get overly hot for long periods in the UK, compared to warmer countries.

I would like to see the boxes adapted for band adjustment. This is possibly not feasible without some dismantling, but would then allow better control of transmission behaviour as it wears.

[CitroJim]

ATF gets hot enough in a 4HP20 on a fine Pom summer day Adam...

Just feel the heat coming off a V6 Xantia after a good run. It's quite enlightening.

[Mandrake]

Normal maximum oil temperature for the HP20 with prolonged "spirited" driving is 100-105 degrees, and I've measured that on mine here in the UK nearing winter...for more casual driving its more like 80 degrees mind you. Since the cooling is provided by the engine cooling system with its thermostat regulation, it shouldn't matter too much what the ambient conditions are as to the final operating temperature, it will just take longer to get there in colder conditions...(assuming the cooling system is in fact working properly)

[begins]

You can fit a sandwich type oil cooler adapter to most AL4 installations. EG: http://www.ebay.com/itm/360484288546" onclick="window.open(this.href);return false; Then add a seven row stacked plate cooler and flex lines between.

What country are you in? ATF doesn't get overly hot for long periods in the UK, compared to warmer countries.

I would like to see the boxes adapted for band adjustment. This is possibly not feasible without some dismantling, but would then allow better control of transmission behaviour as it wears.

Hi there! I'm in Malaysia (average about 30c during the day).

Pardon my ignorance, is this adapter a must in order to perform an ATF cooler installation?

I bought an ATF that looks like the one in the attachment. Mine is a smaller 6 fins model (meat for full size sedan). The one in the picture is a 9 fins model.

This was bought for almost 5 months and I have yet to find someone to fit this for me.

Thank you very much for your information.

Regards,

[addo]

There is a small fluid-to-water oil cooler already mounted on the gearbox; look from the passenger side wheel arch at back of the gearbox following the water hoses. Trans fluid is permitted by the internal thermostat, to pass through this cooler only when up to temperature. To supplement it, you need something like the adaptor I linked.

Make sure you use good quality transmission fluid-rated hose.

[begins]

There is a small fluid-to-water oil cooler already mounted on the gearbox; look from the passenger side wheel arch at back of the gearbox following the water hoses. Trans fluid is permitted by the internal thermostat, to pass through this cooler only when up to temperature. To supplement it, you need something like the adaptor I linked.

Make sure you use good quality transmission fluid-rated hose.

Hi there,

Thank you very much for the advice.

I'm just wondering whether anyone here have added an aftermarket ATF cooler and is kind enough to show me an example? Not many workshops here know about the car .

Regards,