DIY: 2004 V70 2.5T Axle and Seal (110K miles) Volvo 6843112; Corteco 19033885B R side: Volvo 9495018; Corteco 19034

[cn90]

...The axle seal on these cars is there to keep water (and other debris) out, not to keep ATF in...

This is NOT true.

I have done so many seals in P80 and P2 cars.
I am speaking from experience.

The P2 axle seal is there to keep ATF in.

The design of P80 and P2:
- P80: Axle shaft is in direct contact with seal.
- P2: Axle shaft is inside a "cup". The "cup" is in direct contact with the seal.

For both P80 and P2 cars, once the seal is removed, ATF will leak out, maybe around 1/4 qt or so.

[erikv11]

...The axle seal on these cars is there to keep water (and other debris) out, not to keep ATF in...

This is NOT true.

I have done so many seals in P80 and P2 cars.
I am speaking from experience.

The P2 axle seal is there to keep ATF in.

The design of P80 and P2:
- P80: Axle shaft is in direct contact with seal.
- P2: Axle shaft is inside a "cup". The "cup" is in direct contact with the seal.

For both P80 and P2 cars, once the seal is removed, ATF will leak out, maybe around 1/4 qt or so.

Yes, most people who post suggestions here are doing so from experience.

In this case I've swapped probably 20 P80 axles, I know well about ATF leaks, so when I pulled my first two XC70, P2 axles I was surprised to see that in both cases the axles have zero contact with ATF. Not a drop of ATF leaks out and the axle tips are dry or have grease on them. Seems to me that neither one, dry or with old grease remnants, is possible if there is ATF in the cup, but I'm all ears if you can explain it otherwise.

Maybe we both over generalizing by saying "P2" generically. In this thread anyway, we are talking about different P2 transmissions. Devil is in the details!

On XC70 P2 cars with AW55 transmission the axles comes out bone dry, usually with rust patina where the grease has dried up. See pics below. Even the driver's side (shinier one) has rust spots in the grooves among the grease remnants.

07 XC70 axles

[erikv11]

Oh, and TF-80SC passenger axle is the same - comes out bone dry, no ATF in the cup.

[erikv11]

I think I get it: the seal does NOT seal against the axle shaft, it seals against the outside of the cup, right?

So your diagram, and especially the red arrow, in the pic, is wrong? And any text about "the seal groove in the axle shaft" etc. If not, please explain.

Volvo-Seal-02.jpg (198.15 KiB) Viewed 878 times

Volvo-Seal-02.jpg

[cn90]

1. As above - axle seals on these cars will not leak ATF, the ATF is sealed inside the transmission.

2. So fortunately, a right side axle seal leak can *not* mimic a RMS leak.

Seriously,

You go to this forum to spread misinformation?

You are very stubborn, posting wrong info, ppl say it is wrong and you still refuse to see it?

1. That is a wrong statement. Why did the engineers place a seal there? For fun?

2. A RIGHT axle seal CAN mimic a RMS leak, been there done that.

Don't believe me. Fine. Watch the video below.
In contrast to P80, P2 trans has a "receiving cup" (which has a blind end). This is why during a simple axle swap, no ATF comes out. But when the seal is removed, ATF leaks out.
When I have time, I will post a cutaway view later.

For now, this video should be obvious...

[cn90]

The diagram was just for illustrative purpose.

Conceptually, in terms of sealing surfaces:
P2 Axle + blind end cup = equivalent of P80 shaft side.

The blind end cup in P2 has a "shaft side" that is in contact with the seal.

[cn90]

For those interested in the anatomy of P80 vs P2 Axle seal design.
For practical purpose, I call the receiving end "cup" (GREEN color).

Regarding the sealing area:

1- First photo shows the difference between P80 and P2:
---> P80 has a wider shaft area (where it meets the seal).
---> Note that P2 shaft area (where it meets the seal) is smaller. Inside the P2 cup, there is a rubber O-ring to supposedly
keep dirt out of the splines. Good in theory, I always find some rust in there, not a big deal as I always add some grease
during installation.

2- Cutaway diagram to show the difference.
---> This is why when the P80 axle is removed, ATF will leak out.
---> This is why when the P2 axle is removed, ATF will NOT leak out.
---> During seal replacement, BOTH P80 and P2 designs will leak ATF out, not much but about 1/4 qt, maybe 1/2 qt,
depending on the ATF level to start with.

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[erikv11]

@cn90: Thanks for confirming the initial diagram of the seal for P2 cars had a mistake with the red arrow. We are on the same page here.

Updated cartoon P80 vs P2 is way more useful - I get it now!

[cn90]

The RED arrow in the initial diagram is not a mistake.
It simply labeled the "O-ring", which has nothing to do with ATF sealing effect. The "O-ring" is the source of confusion for ppl. The O-ring sits INSIDE the GREEN cup in the above diagram.

All the O-ring does is: to keep dirt out of the splines.

But again, during reassembly, I always add a bit of grease to both the splines and O-ring, which should have been done at factory.

[cn90]

Installing new seal can be tricky as it must be in the correct depth to avoid subsequent ATF leak.

I am thinking about making installation tool (different for L and R side seals). Does anyone know the dimensions of the Volvo factory tools?

I am thinking making the tools using:

1. Wood cut/lathed to correct shape/depth...versus

2. PVC coupler but drill holes (at correct depth) so a long nail can go through. The nail would stop the PVC tool from going deeper than factory.

Attached is just a GENERIC seal installation tool. You can see it is designed for a specific application with certain O.D. (which is a tiny bit smaller than bore diameter) and certain depth...

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