P38A ZF4HP24/22 Fluid Change Procedure.. "How To"

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Think outside, no box required.
somewhere else
Right I've finally got around to doing a proper change on my Autobox in my 4.6 P38..

The first port of call is to choose what oil to put in, if you're a nerd "like me" you look at the Technical data sheet of each particular oil to mainly check

A- Viscosity index
B- Brookfiled Test
C Pour point

etc etc
The main one IMO is A the higher the viscosity index the better the Oil, in simple terms..

Many will say "oil is oil" regardless of brand, and if you buy expensive you're wasting money because it is just a label.

However you'd be both wrong and right, depending on the brand... ;)

In my particular case I spent a good week researching particular oils, looking at prices vs quaility.

My final decision was ELF ELFMATIC for 3 main reasons...

#1 Viscosity index of 186
#2 Brookfield Viscosity of 9828
#3 it meets ZF TE-ML 04D/14A

Those are my reasons, if you go to Opie Oils it lists the Technical data sheets and the MSDS, which is nice..

Compare this ELF VI of 186 https://www.opieoils.co.uk/search/go?p=R&srid=S4-2AWSP&lbc=opieoils&w=dexron 3&url=https://www.opieoils.co.uk/p-205914-elf-elfmatic-g3-automatic-transmission-fluid-atf.aspx&lgsku=205914&rk=22&uid=289255215&sid=2&ts=custom&SLIPid=1595528364378&rsc=vbbq:Hdm1n7n19g3&method=and&isort=score&view=grid

To this Castrol which is very expensive at £11 a litre compared to £7.99 a litre with a VI of 175 https://www.opieoils.co.uk/p-746-ca...tomatic-gearbox-oil-atf-formerly-tq-diii.aspx

Or this Amsoil at £17 a litre with a VI or 165!!!! https://www.opieoils.co.uk/p-1052-a...-transmission-fluid-signature-series-atf.aspx

it is amazing, how they can vary, and how some cheaper alternatives can actually be a far better oil, however don't assume the cheapest shít you can find will be any good..

Engine Oil by comparison is a totally different ball game... ;)

So after all that waffle, to the JOB!! ;)

#1 You need the Fluid and a Filter in my case a set off off Amazon did the trick, sold by JGS 4x4 IIRC

#2 Tools required
1- 3/8 Ratshít with a long extension
2- UJ socket to get access to the awkward bolts at the back of the sump
3- Allen Keys for the sump and filler plug
4- Torx T25 for the Filter and Valvebody screws
5- Plenty of Brake Clean
6- Rags etc.

Climb underneath with a drain pan and drain the fluid, a good piece of advice is to crack off the filler plug first. - Oh and to help yourself later grab a 15mm socket and remove the bolt near the tail end of my Allen, it is for the gearbox mount, this helps with installation of the sump.

Once it has gone from torrential downpour to incontinent poodle, bung the plug back in to prevent the oil dripping down your armpit while you wrestle with the sump bolts.


The sump is secured to the tranny "ha" with 6 10mm bolts, these can be a pain in the arse and they're known to snap off, i've done it twice, on different gearboxes so be careful. :)
the rear most ones which are in close proximity to the gearbox mount/crossmember need a UJ and they can be extra annoying!


Once all these bolts are out and the clamps removed the sump should fall off..
If you're anything like me you were hoping to not see any chunks of **** in there, I however was surprised to see it wasn't too bad..

The Last time this gearbox was serviced - April 2003 at 26k now she is at 127k I did a drain and refil at 125k as a flush, but that doesn't really count as I didn't drop the sump.

In an ideal world "that doesn't exist" you'd want no crap in there at all, however no matter how nice you're to the gearbox it will still wear and you will get material in the sump and on the magnet..
What you don't want is chunks and/or the entire pan covered with what looks like CV grease.. :)

Clean it out properly with brake clean, and lint free rags.

Chuck the seal on.

Now this is done climb back underneath and tackle the filter, this is held on with 3 T27 torx bolts.
seen here.

Pull the screws out and drop the filter, be warned though around 40ml of oil might drip into your mouth or face if you're lying under the pan, or at best it goes down your armpit.. ;)

Once off toss it to one side.

Next up is the thing nobody tells you to do, grab your torque wrench and while the filter is off Re-torque the Valvebody to gearbox securing bolts, I guarantee atleast a few of them will be loose. - 8nm is the setting! DO IT!! If they are loose you bleed Line pressure and your gearbox will slowly become lazy to a point of slurring or worse!

Next up is the Filter, this needs 2 new O rings, they should slip right on, lube them first. - Filter to VB securing bolt TQ figures 8NM

Once done it is time to fit the pan, you remember that pesky bolt i mentioned on the crossmember?
This one? Wind it out to stop the bastard fowling the sump when you're refitting makes life a bit easier eh? ;)

Refit the Sump and torque the bolts down to 8nm

The blurryness isn't tears ;)

Once all done, check around the sump to make sure the clamps are even all the way around and that the seal is still seated..

Next up the Filling procedure...

#1 With the Engine off remove the filler plug and fill with fluid, until it drips out the hole, usually around 2.2 litres is required
#2 Loosely fit the fill plug and start the car, with your foot firmly on the brake go through every gear halting in each for 3 seconds, this allows the pump to suck the fluid up..

#3 Climb back underneath WITH THE CAR RUNNING and remove the filler bolt, add fluid until it steadily pours out the filler plug.

#4 Repeat #2

#5 Recheck, this is for extra OCD points.. ;)

#6 Done!!! ;) :)


Just to put the Strawberry on the cake I'm going to talk a little bit about Lucarse Transmission fix which seems to be a Libation of choice for many with issues.

Most will preach it fixes sticky solenoids, stops clutches disintegrating etc etc

What Transmission fix is in a nutshell is a THICK Atf designed to raise the line pressure in the gearbox to allow whats left of the Clutches to grip, lets face it if you need the stuff your box is either knackered or wearing rapidly, more than likely due to neglect or abuse..

If you read the Blurb " won't fix the gearbox if the clutches/Bands are totally burnt out" ;)

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When I did mine I discovered that two of the bolts had no heads on them. No wonder it leaked. Had to use a stud remover to get 'em out. Luckily replacements are cheap.
Just a Little Addition to the above..

The fluid was changed at 125k now 127k

This is why it is worth running a particular fluid though it for only a few hundred miles to pull the old crap out..
You could do this several times to achieve a 90% change "probably".


New ATF on the right - Old on the left.


A slight colour difference eh! ;)
When i did mine, i disconnected the atf radiator and ran the engine briefly let oil sump from one pipe and filled from the other until it started coming out cleaner. Put it all back together and then checked the level, got through 10 litres and didn't seem to go out any harm. Didn't let it run dry!
GEMS engine you will need to disconnect the dip stick tube prior to dropping the sump and of course fill through said tube. Fluid level checking procedure is the same, except using the dip stick of course.
I drop the gearbox oil every year. The filter every two years.
Lucasfix gave me a sticky second gear solenoid... Ever since I've been rincing it out slowly... Nice heads up for the folks @Henry_b ;)
Who are the mods now?

That AG certainly gets heated sometimes. Must be dealing with it day after day.

I think the tip of the iceberg was some of the comments when all this BLM stuff kicked off, he found it hard to keep neutral with so off the stuff posted and personal stuff that was going on, shame as he was doing a very hard job and i think he did a very good job of it.
at the moment it looks like we have no mods at all.
I think the tip of the iceberg was some of the comments when all this BLM stuff kicked off, he found it hard to keep neutral with so off the stuff posted and personal stuff that was going on, shame as he was doing a very hard job and i think he did a very good job of it.
at the moment it looks like we have no mods at all.

Ah, yes. I did notice some strong emotions going around.