C5 (Series 1) AL4 Auto Oil Change Questions

JAJEA

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300K (actually 290K) kilometres on the odometer about to click over and since it's a while since it has had an ATF oil (or should say ah half) change, I thought that it's about time as with some very hot recent days here in Melbourne - its been misbehaving at times.
Up to now, I've been a great believer if it ain't broke; don't fix it!
So, upon "attempting to do so" and under the great advise of some AF'r some time ago, don't drain the oil, until you locate the filling point. That was a task in its own right. Only after degreasing the top of the AL4, was I able to see it let alone get to it, nevertheless I knew where it was and thus attempted to remove the drain plug.
Armed with the 27mm 3/4" drive socket, I attempted to remove the drain plug but found no 27mm drain plug (and no 19mm oil level plug by the way).

What was/is there is a standard oil drain plug WITH a 8mm Square Drive. I had modified a standard 3" 3/8" extension drive to 8mm by grinding and filing it to 8mm square. This drain plug is so tight that the 8mm square drive started to distort and no doubt shear off if I had continued. So, I sought a proper Chrome Vanadium 8mm plug tool and to my disbelief, (I went to five [5] stores that I expected to have it), they did not know what I was talking about. On Monday, the Bearing place I visit will have enjoyed its holiday and will open - I hope they have *8mm or 5/16" key bars available so I can adapt to another home made tool.

Questions,
1. Why no oil level set up, does this mean, simply drain and add 3l of ATF?
2. Is it possible that previous (dealer) workshops dispensed with the 27mm drain plug and 19mm levelling plug and simply replaced them with a single drain plug.? I can assure you that the previous one owner never touched anything under the bonnet.
3. Is this contrary to available documentation as to how to correctly top up oil level on a AL4 Auto G/B?
4. Our C5 is a late 2004 model, was there a change from the 2 drain plugs to a single drain plug?
5. Why did they do it up so tight that my home made tool failed? My home made tools don't fail by the way.

Best regards,
John
 
Some al4s have a plastic sleeve inside the box for level checking so once that bolt is out you remove it with an Allen key. I believe from memory the one bolt type was a revision. Once you get it apart it will be obvious. I’ve had them pretty tight in the past normally from people over doing it not the factory.
 
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Ah the AL4 oil change process....search AF its all documented. You will need at least 8L to complete the drain and fill process 3 times to remove the contaminated oil from the torque converter and can take 2 - 3L each time.
Never found a 8mm square socket either always cut a 8mm square door handle rod but never that tight to completely distort the rod. A 9mm socket fits over the 8mm square rod.

Penrite is on special ATM at the usual suspects
 

The square sockets are standard tools for PSA cars. If you can't get one at a tool shop, try one of the specialist spare parts places.

The one I most use came from a car parts and tool shop down the road, and is a rattle gun version with 1/2in drive. There was nothing special about it.
 
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Please leave questions on the forum so other people get the benefit of answers.

So David, will I find that plastic sleeve within the filler port upon removal of the filler plug or is it within the drain plug?

The sleeve will be in the drain area it needs to be removed to fully drain the gearbox it takes the place of the large bolt in the other setup.
 
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Hi JAJEA :)
The later models had a revision as said and have a square recess plug, that you found, and up the hole is a plastic tube with a hex hole in it so it can be removed for draining the oil. Then you replace the tube as far as it will go up(not too tight) and that will give the oil fill level. By memory the allen key required is 8MM using the long end.
For 30 years I have used a home made square tool. Renaults use them. I found a high tensile bolt, (check the head markings), and cut off the thread. Check that it is big enough so when grinding the round shank to square it is the correct size with full corners. Do not soften it by getting it hot, use water dipping. Then use a socket on the head. I had found that the cheaper small socket drivers did distort on tight plugs as they have a ball hole in them and are cheap shit too.
Good luck. Do not forget that the level must be done WITH THE ENGINE RUNNING and quite warm(almost too warm to hold your hand on). So prepare before you start the job. And leave it several hours to drain and that will get a bit more out. Use Penrite FS auto fluid.
Jaahn
PS I note the search function is now shite and cannot find any old threads IMHO.
 
Thanks Gents.

I thought I had done my homework on this but I do not recall any reference to what appears to be a "standard" drain plug.

Dmccurtayne is obviously right - there has been a design change. (And also right, that some over zealous guy/gal over tightened it.) I just hope that I don't strip the 8mm key hole and have to drill the plug out.

I propose to leave the new oil a few thousand Km's before changing again and will decide on a 3rd on how it behaves after the second change.
I actually got a spare 9mm socket ready before running off to CBC and was going to epoxy the key steel in and keep as a permanent tool. Just hope that my local CBC store has it or can get it.

Sign of the times that all the sales people in stores (including a humongous "JustTools" and Bursons) did not know what I was talking about despite having the damaged home made tool to show them. No PSA car owners amongst them, that's for sure.

Aliexpress have hundreds at around AU$3.00 each. If I'm unsuccessful in acquiring 8mm key steel, I'll be chasing Aliexpress - any body interested in one if I go down that path as it will cost more in postage that the item itself.

John

PS: On reflection I remember that I did not grind it but filed it down to ensure no loss of strength - it's b@#$dy tight!
 
Thanks jaahn, just noted upon sending previous post.

PS: I actually bypassed the hole and filed onto the shank of the 3/8" drive but you are spot on, it is a cheap shite one as I did not want to destroy my Sidchrome set.
PPS: And yes, I did consider filing down a high strength bolt but the 3/8" drive was readily available and would have worked if not so tight.
 
5/16" or 8mm key steel is soft steel.
It is made to be a shear point as a protection for the mechanical device.

It is not suitable as a driving tool.
Door handle square is probably no better.

My suggestion is to buy a 1/2" drive 10mm hex driver, and grind it back to 8mm square. When grinding don't let it overheat, or the temper of the steel will be lost. Grind a little, dip it in water, measure, grind a little more, dip it in water, measure......etc.
Be patient, and you will get a tool better than any available of the shelf.
 
Hi JAJEA :)
The later models had a revision as said and have a square recess plug, that you found, and up the hole is a plastic tube with a hex hole in it so it can be removed for draining the oil. Then you replace the tube as far as it will go up(not too tight) and that will give the oil fill level. By memory the allen key required is 8MM using the long end.
For 30 years I have used a home made square tool. Renaults use them. I found a high tensile bolt, (check the head markings), and cut off the thread. Check that it is big enough so when grinding the round shank to square it is the correct size with full corners. Do not soften it by getting it hot, use water dipping. Then use a socket on the head. I had found that the cheaper small socket drivers did distort on tight plugs as they have a ball hole in them and are cheap shit too.
Good luck. Do not forget that the level must be done WITH THE ENGINE RUNNING and quite warm(almost too warm to hold your hand on). So prepare before you start the job. And leave it several hours to drain and that will get a bit more out. Use Penrite FS auto fluid.
Jaahn
PS I note the search function is now shite and cannot find any old threads IMHO.
Hi Here is an old thread about the oil change. All I could find. There is some BS said but go to the end P4 for some pictures of the plug and level tube , and removal of tube.
https://aussiefrogs.com/forum/index.php?threads/al4-auto-finally-smooth-shifting.105534/page-3
Jaahn
 
5/16" or 8mm key steel is soft steel.
It is made to be a shear point as a protection for the mechanical device.

It is not suitable as a driving tool.
Door handle square is probably no better.

My suggestion is to buy a 1/2" drive 10mm hex driver, and grind it back to 8mm square. When grinding don't let it overheat, or the temper of the steel will be lost. Grind a little, dip it in water, measure, grind a little more, dip it in water, measure......etc.
Be patient, and you will get a tool better than any available of the shelf.
Thanks Buttercup, that's one method I did not think of. I like it.

Nevertheless, I need to correct you in that key steel is not "soft" steel. It can't be as it needs to transfer power from shaft to pulley/gear and vice versa. It may not be too high in UTS but certainly higher than mild steel.
 
I disagree....... strongly!
Keysteel is made to shear.
I didn't say it was mild.
It has very low toughness which means it is the exact opposite of the steel you need for a driving tool.
Keys are designed such that the key will shear before other parts are damaged. This is achieved by using a soft steel, softer than the parts it connects, and the shear area is calculated to provide the drive needed, but not much more.
If a key was harder than the parts it connects, the edges of the keyways would be deformed.
There are a variety of keysteels available, and are selected according to the hardness of the components being connected, but none of them is tough or appropriate to from a driving tool.
Your El Cheapo 3/8" socket extender bar would be better steel than any key.

Another option is to use a piece of HSS toolsteel.... available as a 5/16" bar...
 
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What's so hard about buying an 8mm tool? You can buy them at tool shops, Peugeot/Citroen parts sellers, some wreckers, ebay, etc. I think I remember French Connection having them.
 
Hi Here is an old thread about the oil change. All I could find. There is some BS said but go to the end P4 for some pictures of the plug and level tube , and removal of tube.
https://aussiefrogs.com/forum/index.php?threads/al4-auto-finally-smooth-shifting.105534/page-3
Jaahn
Thanks jaahn, I had read / studied bdlow's advice but did not understand the 8mm(?) allen key "up the drain pipe" removes the level tube within the AL4's sump as it is so different to the 27/19mm drain plugs. I do know.
John
 
This is my lathe chuck key that I made 28 years ago, from the shank of a broken 1" HSS thread tap.

That is VERY tough steel!
20210110_135003.jpg
 
Update.

Drained 3 litres, put in 3 litres. No time to add the extra 500ml and drain while running (I had to vacate workshop).

For anybody interested in the "8mm" square drive to remove plugs. French Connection not open (I believe are on their well earned break) and JustTools Tullamarine is one of the biggest around and they did not have. Hence, as there are some trips for the C5 coming up, ATF change quite appropriate and necessary as previously advised, it has been misbehaving on occasions and it has not had an oil change for years [not broken, don't fix].

Without any further ado, I had little to lose in adopting and adapting key steel plus 9mm socket plus epoxy putty, tool was ready in no time.

Happy to report that whilst the home made ground down to 8mm square 3/8" extension previously failed, this one did not. The 9mm socket used had the 3/8" drive and hence I used the Sidchrome 3/8" ratchet with no luck; far too tight. Grabbed and adapter and used the Sidchrome 1/2" 300 mm drive bar, again no luck - too tight. The 600 mm long tube did the trick even though, the "crack" when it gave way gave me a fright in that I thought it sheared off. It DID NOT. I reckon I used considerable effort at ~ 500 mm moment length compared to my maximum ability at the standard 300 mm long 1/2" bar.

So, key steel will do the trick (or maybe not if the plug been done up harder than mine - but I don't think that anybody could have done it up any tighter without damaging the AL4 case).

Once again, thank you all for your assistance,

Regards,

John

PS: PS: Quite happy to part with a 20mm length of key steel as I had to purchase the full 300mm bar.
 
I just bought an 8mm square tool.

There are plenty on eBay and they are not difficult to find or expensive.
 
I just bought an 8mm square tool.

There are plenty on eBay and they are not difficult to find or expensive.
Yes, but the issue was timing with me with the failure of the home made one - boy was that sump plug tight. You have to wait for it to be delivered unless you are lucky enough for the supplier to be near by and allows pick up , my job is finished,
Regards,
John
 
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