PSD diff oil spec
Former Vendor
Joined: Feb 2005
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From: Anaheim
I am convinced there is something in what you said- not sure if I mentoned it earlier but after I found the Mobil 1 locally and not sure whether I was being taken for a ride, I immediately cross checked pricing on Amazon UK and Amazon.com. In the UK no sign of LS, On the US website the first two entries were LS variants and then a third Mobil variant called Delvac 1 whatever that is but no sign of the variant I purchased.
Mayb ein the States obsessed by low sugar maybe" LS" means more from a marketing psychology point of view?
Mayb ein the States obsessed by low sugar maybe" LS" means more from a marketing psychology point of view?
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From: Oman
Given that the LS variant is perfectly useable in an open diff maybe they simply market the same thing differently in different markets. At the end of the day they are offering a fixed volume of the product and who knows maybe the additive is cheaper than the unit cost of the oil!
Either way what I have is going in the diff as soon as I can resolve the seal issue one way or another.
Either way what I have is going in the diff as soon as I can resolve the seal issue one way or another.
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From: Oman
Well I was under the car this afternoon preparing for the tasks I have in mind for the rear of the car that including changing the ATF and diff oil and replacing rubber section of the two ATF cooler lines. I noted tha tone of the lines has a union but the other does not soI will have to cut off the crimp ferrule in-situ as it were.
Anyway I am still contemplating my next course of action with the half shaft seals and whilst under the car I then realised that something strange appeared to be the case. Although there are clear signs of oil mist on the half shaft hub the outside of the stub axle shows no signs of oil whatsoever and same on the other side. This lead me to conclude that if it is diff oil it can have come from the inside [erhaps via the mouunting bolt stem or could it be that some oil has migrated from the grease pack that /i pumped in there are few years ago and it is seeping out?
Anyway I am still contemplating my next course of action with the half shaft seals and whilst under the car I then realised that something strange appeared to be the case. Although there are clear signs of oil mist on the half shaft hub the outside of the stub axle shows no signs of oil whatsoever and same on the other side. This lead me to conclude that if it is diff oil it can have come from the inside [erhaps via the mouunting bolt stem or could it be that some oil has migrated from the grease pack that /i pumped in there are few years ago and it is seeping out?
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From: Oman
Today I started work on my general service itemsand started with the diff oil change. I had previously loosened the plugs as per GB's advice and opened the top plug, a little oil oozed out suggesting correct fill levels and it was a clear brown colour- good I thought.
I then dropped the drain plug and caught the oil that came out- I was shocked! The plug had no particulate matter stuck to it - just this thick sludgy black stuff. I caught aobut 2.5 litres of oil and being cold, i figured more will still slowly drain so left that accumulate before trying to drain some more.
I was totally dismayed by the visual appearanc eof the oil- of course the car has been static sat on my home brew liftbars/axle stands for over two weeks so can understand some settlement as it were but now the $64 question is what is that black gunge? I suppose it is feasible it could be caused by clutch plate material gradually wearing but is tis a normal thing when draining diff oil? Now I am wondering the oil was ever changed out when I instructed them to do so 10 years ago.
Any thoughts?
I then dropped the drain plug and caught the oil that came out- I was shocked! The plug had no particulate matter stuck to it - just this thick sludgy black stuff. I caught aobut 2.5 litres of oil and being cold, i figured more will still slowly drain so left that accumulate before trying to drain some more.
I was totally dismayed by the visual appearanc eof the oil- of course the car has been static sat on my home brew liftbars/axle stands for over two weeks so can understand some settlement as it were but now the $64 question is what is that black gunge? I suppose it is feasible it could be caused by clutch plate material gradually wearing but is tis a normal thing when draining diff oil? Now I am wondering the oil was ever changed out when I instructed them to do so 10 years ago.
Any thoughts?
Burning Brakes
Joined: Jun 2004
Posts: 894
Likes: 230
From: The Great White North
Today I started work on my general service itemsand started with the diff oil change. I had previously loosened the plugs as per GB's advice and opened the top plug, a little oil oozed out suggesting correct fill levels and it was a clear brown colour- good I thought.
I then dropped the drain plug and caught the oil that came out- I was shocked! The plug had no particulate matter stuck to it - just this thick sludgy black stuff. I caught aobut 2.5 litres of oil and being cold, i figured more will still slowly drain so left that accumulate before trying to drain some more.
I was totally dismayed by the visual appearanc eof the oil- of course the car has been static sat on my home brew liftbars/axle stands for over two weeks so can understand some settlement as it were but now the $64 question is what is that black gunge? I suppose it is feasible it could be caused by clutch plate material gradually wearing but is tis a normal thing when draining diff oil? Now I am wondering the oil was ever changed out when I instructed them to do so 10 years ago.
Any thoughts?
I then dropped the drain plug and caught the oil that came out- I was shocked! The plug had no particulate matter stuck to it - just this thick sludgy black stuff. I caught aobut 2.5 litres of oil and being cold, i figured more will still slowly drain so left that accumulate before trying to drain some more.
I was totally dismayed by the visual appearanc eof the oil- of course the car has been static sat on my home brew liftbars/axle stands for over two weeks so can understand some settlement as it were but now the $64 question is what is that black gunge? I suppose it is feasible it could be caused by clutch plate material gradually wearing but is tis a normal thing when draining diff oil? Now I am wondering the oil was ever changed out when I instructed them to do so 10 years ago.
Any thoughts?
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From: Oman
Burning Brakes
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From: The Great White North
If you were to put anything other than the proper gear oil in there and drive the car, it would destroy the clutch plates in short order. If you were going to flush it, I'd do it with new gear oil, drive for 100 miles (and do a lot of tight figure 8s in a parking lot) and then do another fluid change.
I usually take the diff apart every ~5 years to replace the clutch plates so it gets cleaned at that time, but I have the mechanical LSD which doesn't have the hydraulic fluid lines pressurized to ~2600 psi so I don't know how much more difficult it would be to remove and open up the PSD diff. Do you do the PSD fluid flush every 2 years?
I usually take the diff apart every ~5 years to replace the clutch plates so it gets cleaned at that time, but I have the mechanical LSD which doesn't have the hydraulic fluid lines pressurized to ~2600 psi so I don't know how much more difficult it would be to remove and open up the PSD diff. Do you do the PSD fluid flush every 2 years?
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From: Oman
The key word was flush- not drive- something along the lines of a thinner fluid to pick up any residual crap.
I do the PSD flush every couple of years or so along with the brakes - will probably do mine in the next day or two while the fuel tank is still out of the car- makes it a lot easier to get at the bleed nipple on the slave unit- no impact on the rest of the task- just have to purchase some brake fluid. I have one of those pressure bleeder kits so may actually try to use it!
I do the PSD flush every couple of years or so along with the brakes - will probably do mine in the next day or two while the fuel tank is still out of the car- makes it a lot easier to get at the bleed nipple on the slave unit- no impact on the rest of the task- just have to purchase some brake fluid. I have one of those pressure bleeder kits so may actually try to use it!
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