Which of these 3 oils would you chose for the differential?

[SalvadorP]

All are synthetic, hypoid, GL5, Mil L 2105 B or C.
I'm inclined to get the Valvoline, but I have Liqui Moly on my M90 and I have had no issues. What would you choose?

18,25€/L


14,85€/L


12,25€/L

[baggy798]

The cheapest one! Splitting hairs but 80w90 is what the owner's manual calls for.

[SalvadorP]

Originally Posted by baggy798

The cheapest one! Splitting hairs but 80w90 is what the owner's manual calls for.

still need to check whether or not the diff has LS. I can't find the damn sticker. I am assuming it doesn't. because if it does, i heard it needs LS oil

[SalvadorP]

Originally Posted by baggy798

The cheapest one! Splitting hairs but 80w90 is what the owner's manual calls for.

btw baggy, you are a resourceful dude, have you by any chance come accross any way to fix replace the heater vacuum bellow/servo?

I'm pretty sure mine is done for and I've been searching all day. If you don't know what I'm talking about, it's this part: 9463042
The rubber diaphragm goes bad and the part ain't available anymore. Some german or dutch guy found out a GM part is pretty similar but it is expensive (about 60 pounds plus shipping from US). I'm looking at diaphragms on aliexpress that might fit or be repurposed, but no luck yet. Some german dude did have the same idea and sucessfully used a rubber nipple but didn't reveal where he took it from.
I already have the measurements of the thing, more or less, so I might do a mold and cast a few of those suckers in silicone, if I don't find another way, that is.

[Forrest]

If you can get the thing apart in a non-destructive way then you have two options. Either repair the existing diaphragm with a patch and/or plasti-dip or fashion a new diaphragm out of suitable thickness nitrile rubber sheet.

I have quite a collection of failed VW/Pierburg 2e2 throttle actuators which I plan to try to repair one day along the lines of this method.

https://www.landrovermonthly.co.uk/a...e-unit-repair/

Not sure whether the plastic body would make the job easier or worse. On balance, I’d probably go for new AC Delco units.

The single-port vacuum bellows is Delco part number 15-71503. The twin-port vacuum bellows is Delco part number 15-71438. This Finnish forum has pictures of them and the Volvo parts side by side.

https://www.vrcf.fi/foorumi/index.php?topic=25022.60

[SalvadorP]

Originally Posted by Forrest

If you can get the thing apart in a non-destructive way then you have two options. Either repair the existing diaphragm with a patch and/or plasti-dip or fashion a new diaphragm out of suitable thickness nitrile rubber sheet.

I have quite a collection of failed VW/Pierburg 2e2 throttle actuators which I plan to try to repair one day along the lines of this method.

https://www.landrovermonthly.co.uk/a...e-unit-repair/

Not sure whether the plastic body would make the job easier or worse. On balance, I’d probably go for new AC Delco units.

The single-port vacuum bellows is Delco part number 15-71503. The twin-port vacuum bellows is Delco part number 15-71438. This Finnish forum has pictures of them and the Volvo parts side by side.

https://www.vrcf.fi/foorumi/index.php?topic=25022.60

Yes forrest, i've seen that.

Look at this. This fella dismantled the thing. It is in german, but the translator does a good enough job:
https://volvo.reparaturanleitung.inf...anleitung-pdf/

And more pictures the same guy published. Here you can see how he disassembled the thing:
https://volvo.reparaturanleitung.inf...kuummotor-pdf/

Mine is a twin-port, I guess. ECC. I'm gonna try to see if someone has any from a parts car. But chances it is still good seem to be slim.

[Forrest]

I like his method of fixing it back together with machine screws and nuts around the edge. I think I’d have used J-B Weld though.

[SalvadorP]

Originally Posted by Forrest

I like his method of fixing it back together with machine screws and nuts around the edge. I think I’d have used J-B Weld though.

That was a weird choice wasn't it? But the guy says he stress tested the assmbly with this nipple 10k times in a lab setting. Maybe he is an engineer. And that would explain the screws. It's because he had to test several diaphragm solutions, so screws and silicone were the answer. He couldn't just weld it together. He does say in the text that it wasn't even necessary to open the servo. And i've seen other prople do it without opening the servo.
I've also found a guy that did this but replaced the diaphragm with the GM one. Because while the parts are not exactly the same, the diaphragm is.
https://volvo700vereniging.nl/interi...o-ac-ventielen

How do you recon he did the metal tip/hook? I can't figure it out from the text. It has to come out for the new diaphragm to go in. It looks like it is a different part. Can't understand if he welded it. The part doesn't even look to be the same. I think it might be possible to cut the welds out with a dremel and jbweld it back together.

[360beast]

I used Castrol transmax 80W90 EPX in the diff of my 940.

If you have a G80 don't use LSD oil as it isn't a Limited Slip Diff it is an automatic locking differential, I'm pretty sure the G80 uses the same conventional 80W90 GL5 oil, I could be wrong on the oil grade for a G80 but definitely don't use LSD oil.

[SalvadorP]

Originally Posted by 360beast

I used Castrol transmax 80W90 EPX in the diff of my 940.

If you have a G80 don't use LSD oil as it isn't a Limited Slip Diff it is an automatic locking differential, I'm pretty sure the G80 uses the same conventional 80W90 GL5 oil, I could be wrong on the oil grade for a G80 but definitely don't use LSD oil.

I don't know what G80 refers to. is it the 1041 diff? I know if it is marked 1041, it is a auto lock. If it is marked 1031 it can have the dealership installed Limited Slip option. I heard they normally put a plate on the diff case alerting to use LS oil, but the only way to be sure is to read the tag, which I can't find on mine. Either I'm not seacrhing in the right place or it is gone.