Powershift Primary Oil Filter Replacement

[AlanM]

A really poor bit of design: The primary oil filter in the Getrag 6DCT450 (officially) cannot be replaced without removing and completely dismantling the transmission. Even worse, with the valve body cover and the valve body itself removed, you can see and get hold of the filter.

But it can be done. All you need is a bit of determination and a heat gun. The torx screw that retains the filter is where the determination comes in. It's quite tricky to access, you can only move it a fraction of a turn at a time, and it is RIDICULOUS how long it is, given the job it does.

But eventually it'll come out.

Then, to get the old filter out you just remove the magnets, which gives a bit more clearance, and use the heat gun to soften the plastic top half of the filter a bit. Then push it down while levering it out. You have to deform the top half by enough to get the spigot out of the oil pump inlet. It's actually not much, maybe about 10mm.

Getting the new filter in is pretty much the reverse process. A bit of heat (I had the gun set to 150C) to allow the filter top to flex without cracking and a blunt lever, (I used the handle of a small hammer) you push the top of the filter down and in, getting the spigot under the oil pump pick up.

Once it's under you can push it back and forth until the spigot pops up into the pick up. Then a couple of screwdrivers under the filter to push the spigot all the way in.

Now comes the hard part: getting that ridiculously long screw back in. I actually ground the tip of the screw into a bit of a point, since there's no way of seeing when the screw hole in the filter is aligned with the hole in the oil pump pick up. Grinding a point helps it to align itself.

Then it's just another 45 minutes screwing it in a 16th of a turn at a time... it probably wasn't that long but it seemed longer.

So anyway, it can be done, and a lot quicker and less work than removing and splitting the transmission.

[oldgun]

the question is , do you have to replace that main filter which is only for big chunk of particles.

[AlanM]

Originally Posted by oldgun

the question is , do you have to replace that main filter which is only for big chunk of particles.

It's a paper filter, not a strainer, so it would get at least partially blocked by just the material that comes off the clutch plates. The magnets in these boxes get a thick coating of sludge on them, and they certainly wouldn't be as effective once covered like that. So that leaves the other two filters to keep the muck out. But the external one is in line with the oil cooler so only actually works when the oil is hot. All the oil constantly circulates through the internal one so having a clean one in there certainly can't hurt.

These transmissions rely on oil pressure to properly engage the clutches. The internal filter is on the suction side of the oil pump so restrictions here could quite possibly impact on the operation.

[AlCan]

Sounds like a real mission.


Did you happen to take any photos while you had it apart?


I had no idea that filter was paper. I totally agree, really lousy design. No wonder Getrag changed their name. Such a shame, as some parts of the transmission are very smart. But it can't be allowed to last too long, right!?

[AlanM]

The hardest part is getting the screw out and then back in. There's not much access to it.

Actually getting the filter out and in isn't so bad, once you heat it up a bit to get a bit more flex.

The filter element itself is like a bag, with the opening at the intake hole, which effectively doubles the surface area.

Sorry, I didn't take any photos, but there is a YouTube video on a channel called "Life on octane".

[oldgun]

Managed to get the job don, took 3 hours with heat gun.

[AlCan]

Thanks Alan,

This is very helpful, especially the video pointer.

For ref, it's here: https://youtu.be/ULCgqmGZ9tY

Hand held camera which is very busy, but you do get a few glimpses of the paper element inside the plastic and steel filter box. Looks awfully thin!

Originally Posted by AlanM

The filter element itself is like a bag, with the opening at the intake hole, which effectively doubles the surface area.

Sounds very like a disposable vacuum cleaner bag.

I guess this construction explains why the transmission suffers mechatronic faults after 1-200,000km or so of not getting transmission servicing. Still guessing, but my guess is that once that paper bag gets thoroughly clogged and the pressure drop goes up, it tears open...

Hmmm. Is that external filter even in the oil flow path to the control components, or is it just a bypass filter? Maybe that's why the primary, paper bag filter is so much finer than a steel mesh or similar pickup would be.

Like it's designed to punish those who don't pay for regular transmission servicing.

So, many thanks for this post, I'm off to buy a primary trans filter asap!

Anyone have any idea of what the oil pressure is at the pump outlet? Maybe that plastic external filter housing wouldn't be up to it.

[AlCan]

Uhh... Can't edit last post, but I see now that the external filter is connected via low pressure hose and hose clips, so can't be much pressure there. Must be a bypass filter.