C5 4HP20 oil level

[andybsmith]

How on earth do you check the oil level on this box, there is no dipstick and I cannot find a level plug, reading various other forums there is some mention of a combined drain/level plug mine just has a single piece drain. Also the oil I have bought for it from GSF is Carlube Fully Synthetic ATF-U, having read horror stories about using the wrong oil I need to know that this is the right stuff.
Any help/advice would be really usefull guys (and gals)thnx.

[Bandit12]

Hi Andy

Checking and changing the oil on this particular gearbox is a bit of a faff requiring a lexia.

The oil you need is Mobil LT71141

http://www.opieoils.co.uk/p-69401-mobil ... fluid.aspx" onclick="window.open(this.href);return false;

ANTHING else will destroy the gearbox. Do you have gearbox issues at the moment?

As it is such a pain to just check the oil level you might as well just change the fluid at the same time. You will need

A lexia diagnostic tool to check the oil temperature in the gearbox.
5 litres of oil (only 4 will drain out but its best to be prepared.
very small funnel
spirit level to make sure car is level in all axis
A couple of hours with nothing else planned.

Ensure car is completely level both front to back and side to side.
Remove the airbox which will reveal a small blue plastic plug ontop of the gearbox, this is where the oil goes in. Underneath and on the side of the gearbox are 2 plugs with allen key slots.
Warm the engine up and remove the blue breather cap ontop of the gearbox, it is just a push fit so a pair of needle nose pliers carefully placed underneath it will lever it up.
Loosen the level one first then loosen the drain plug and drain the oil. It should come out very dark or even black. After about half an hour put both plugs back in, the drain plug tight and the level plug finger tight.
Hook car up to the lexia and select the correct page for the gearbox oil.
Carefully put in 4 litres of oil into the gearbox(dont spill any on yourself cos it smells like cats wee!)
Start car and warm up. When gearbox oil temperature is between 55-60 degrees C (might need to double check that as working from memory) Still with the engine running undo the level drain plug and prepare to catch about half a litre of oil.
Keep the engine running
When the oil slows to a drip and it still between 55-60 degrees C put the level drain plug back in and do it up tight. Double check both drain plugs, put breather plug back in to top of gearbox, put airbox back and unhhok the lexia thentake car for a steady drive for a few miles to make sure its working then park up and look underneath car for any sign of fresh gearbox oil leaks.
It now should be ok to drive.

One vital thinkg to remember is cleanliness. Make sure that no dirt or grit goes into the gearbox especially around the breather cap. These gearboxes are great but they are fussy and susceptable to grit damage.

Have fun:-)

Bandit

[1997V6]

I didn't have a Lexia, so, as I had no leaks from the gearbox, I replaced like with like.
Draining is only partial, since the converter cannot be totally drained, (there should be around 7.7 to 8.3 litres in the box). The more changes you do, the more old oil gets exchanged for new. I did 3 changes, using 10 x 1 litres of Mobil ATF LT71141.

After taking the car for a drive to warm up the gearbox oil, I removed the small blue plastic plug on top of the gearbox (as per Bandit12), then drained as much as possible from the drain plug (see below for volumes removed/replaced each time).
I used a glass measuring jug to check the exact volumes removed. Each time I drained the box, I marked the glass jug with a felt-tipped pen with the levels of old oil, and, after cleaning out the jug, replaced to the same marked level with fresh, prior to filling the gearbox with it. I did this 2 years ago, and, touch wood, everything is fine.

My gearbox drain sequence:
Date: 20130609
Drain 4 Litres and Fill at 100,400 miles. Engine cranked for extra oil.
Date: 20130616
Drain 3.75 Litres and Fill at 100,770 miles. 3 new put in, plus 0.75 litres from drained.
Date: 20130728
Drain 3.75 Litres and fill 102364 miles. 3 new put in, plus 0.75 litres from drained.

I got my oil from Opie Oils, the same as Bandit12's link, as they had an offer at the time. At the moment, you can get it cheaper on Ebay:
http://www.ebay.co.uk/sch/i.html?_nkw=m ... 141&crdt=0" onclick="window.open(this.href);return false;

Final notes, filling the box through the funnel via the small hole where the blue plastic plug is removed, can take a long time, as pressue builds in the box when the air cannot be displaced. When this pressure stopped the oil draining through the funnel, I used a drinking straw, placed my finger over the top, inserted the straw through the oil filled funnel, removed my finger and the excess air came out. I used Halfords Small Orange Funnel.

[andybsmith]

Thanks for the advice guys, I'm now thoroughly confused as the carlube oil gfs sold me is up to LT71141 spec, I don't have a lexia yet so my plan was to drain 2 litres at a time and run for a hundred miles or so inbetween changes. The box doesn't seem as silky smooth as it was especially when cold.

[1997V6]

I wrote to ZF UK, they confirmed that the ZF 4HP20 autobox should use ZF Lifeguardfluid5 (ZF No. S671 090 170), and recommend an oil change at 60,000 miles.
They also listed vehicle manufacturer's part numbers to be used in the ZF 4HP20, which can be looked up in this PDF:
http://www.zf.com/global/media/en_de/lu ... -ML_11.pdf" onclick="window.open(this.href);return false;

One of ZF's frequently asked questions:
Q. Can I fill my ZF automatic passenger car transmission with aftermarket fluids?
A. It is not recommended by ZF to use any lubricant other than those specified (see lubrication list). Use of any lubricant other than those specified by ZF may cause extensive damage to the clutch plates, torque converter and mechatronic adaptions resulting in poor shift quality and shortened transmission life.

Here's an interesting video from ZF on changing the Oil/Filter. The pump is a useful item!
http://www.zf.com/na/content/en/united_ ... ts_us.html" onclick="window.open(this.href);return false;

[andybsmith]

Thanks to all you respondents especially 1997v6 for your very informative reply, on balance I think that the fluid GSF supplied can go back and I'll order some Mobil fluid instead.

[CitroJim]

Thanks to all you respondents especially 1997v6 for your very informative reply, on balance I think that the fluid GSF supplied can go back and I'll order some Mobil fluid instead.

Yes, definitely use only genuine LT71141...

If you want, PM me with an email address and I can send you the official words on checking HP20 oil levels and more besides...

[Oxbridge1996]

Hi folks - I'm new to FCF and appealing for your help and advice. I have a 2003 C5 2.2 SX with a ZF4HP20 auto gearbox. The valve block cover [sump] has weathered badly over the years and is now weeping ATF from the lower half. I've got a new cover and a new gasket, but I would appreciate some advice on the oil. Here's where I'm at: the original Citroen part number is 9736.22 which as I understand it = LT71141. I spoke to Citroen a few days ago, they said this has been superseded to 9730AF. However, ZF now recommend 'Lifeguard Generation 5', but all the old oil would need to be drained, which would mean the transmission would need to come out to get the oil in the torque convertor. My gut feeling is to stick with the original spec LT71141. Westway Lubricants list LT71141 on ebay [6 litres for £42.00] - https://www.ebay.co.uk/itm/114262929867 ... SwExVe6c7i - so my question is 'will this do the job?'

[GiveMeABreak]

Why would you need to take the gearbox out?

I appreciate you cannot completely drain the gearbox when refilling as about a third will remain in the TC, so it usually takes 3 drain and refill procedures over a few months to get as near a full change as you can.

I would suggest you consider a drain and refill using the correct procedure which is done in situ, then repeat the change in a few months if the oil is still grotty.

[CitroJim]

Yes, definitely stick to LT71141. And as Marc advises.

These 'boxes are quite sensitive to oil and problems can result in using alternatives...

It's usual for the valve cover to look 'weathered' but I've never seen one rust through... Yet!

Be aware that when you change the cover absolute clinical cleanliness is required as no dirt or debris must be allowed to enter the gearbox.

[Oxbridge1996]

Hi folks - thank you for the excellent replies and advice - I'm very grateful. I'll post a pic when I get it off. The top half of the pan is fine - looks like new, the bottom half not so.

[CitroJim]

I'm very grateful. I'll post a pic when I get it off. The top half of the pan is fine - looks like new, the bottom half not so.

Looking forward to seeing it! And I trust you'll not find the job too difficult...