i read in a pi motorsports mag that i should use a lsd oil, i have my doubts though.
please anyone know.
cheers
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Castrol 80W90 Hypoy C GL-5 gear oil. Butfoy told me this 20 years ago when he rebuilt mine. Never had a problem.
quote:Castrol 80W90 Hypoy
This is the old name & was renamed in Nov 2011 to AXLE LIMITED SLIP 80W-90.
Kev, welcome aboard.
What you read was correct, the gearbox lubricant does indeed need to satisfy the requirements of a limited slip differential ... plus the spiral/bevel ring and pinion gears, bearings of all types, transmission gears and the synchronizer rings. The lubricant must also be non-corrosive to steel, aluminum, and "yellow' metals (i.e. copper, brass or bronze).
ZF's recommended viscosity was SAE 80 or SAE 80W90. The synchronizers, brass/bronze parts and limited slip differential within the gearbox has traditionally meant lubricants rated API GL-4 are the best lubricants for the ZF. GL-4 lubricants are medium load lubricants in which the additive package has been specifically formulated to meet the requirements of limited slip differentials and synchronizer rings, while being non-corrosive to aluminum and yellow metals. API GL-4 lubricants are common lubricants for transmissions and transaxles. The Castrol 80W90 Hypoy Gear Oil (GL-4) was among the lubricants ZF originally recommended to Ford.
GL-5 lubricants have a higher load rating than GL-4 lubricants, but the GL-5 additive package is usually not compatible with limited slip differentials or synchronizer rings; the GL-5 additive package is usually corrosive to yellow metals too. However, some API GL-5 lubricants contain friction modifying additives specifically added for limited slip differential usage (the label should specify it has a modified API rating such as GL-5+ or GL-5-LS). API GL-5 lubricants are common lubricants for axles that are independent from the transmission. Even when modified for limited slip differentials GL-5 lubricants are not usually considered suitable for the synchronizer rings & yellow metals in a transmission or transaxle. However in the case of Castrol's current 80W90 Hypoy Gear Oil (which is rated API GL-5) Lloyd's recommendation indicates to me it must be OK for the ZF. 
At least now you understand the issues.
i still have this from a delivery limited slip differential for my SRT10 Viper at the time...
http://www.xentxsynergyn.com/s...12-1-qt-bottles.html
the bottles claim suitable for LS and GL3,4 and 5
know ?
http://www.xentxsynergyn.com/s...12-1-qt-bottles.html
the bottles claim suitable for LS and GL3,4 and 5
know ?
can we , not knowing what's in it , make a harmfull mix ?
As Bosswrench mentioned we only refresh 2.5 liters of the total 3.5 liters... so 40 % remains the old oil.
Give it a spin and refresh again : remains 13% mix , do it a third time and we got 7 %.
so you need 7.5 liters fresh oil ...
As Bosswrench mentioned we only refresh 2.5 liters of the total 3.5 liters... so 40 % remains the old oil.
Give it a spin and refresh again : remains 13% mix , do it a third time and we got 7 %.
so you need 7.5 liters fresh oil ...
If there were only two lubes available, Castrol 80w90 limited slip and Redline 75-90 ns, which should we choose?
Steve
Steve
Butfoy tells Panterapatt to use GL-5 oil and then in the RBT FAQ section,it says that GL-5 oil will require harder shifting?
Redline is also GL-5 rated, btw.
WTF?
Redline is also GL-5 rated, btw.
WTF?
Why not run Brad Penn GL-4? It works very well in a ZF and is what was specified from the manufacturer. If you want a synthetic, then Pennzoil makes a great GL-4 specific one, but you will need to buy a case and it is expensive. I switched to the Pennzoil synthetic because I live in a cold climate and it did improved the shifting when cold, but did not improve the shifting when hot over the Brad Penn gear oil.
Summit racing sells the Brad Penn GL-4 oil and can have to your door in a few days.
Summit racing sells the Brad Penn GL-4 oil and can have to your door in a few days.
Roy Butfoy, the master rebuilt my ZF 20 years ago. As I was leaving Lance's shop, he looks at me and says "change it once a year, and use Castrol 80W90 Hypoy C." Use nothing different, and never do not change it once a year."
I never forgot what Roy told me and I have faithfully done that. Roy didn't say GL-5. He just showed me the bottle and said buy this.
I live in SoCal, and my ZF shifts like butter, does not leak and is perfect.
So that is what I choose to use.
Lee
I never forgot what Roy told me and I have faithfully done that. Roy didn't say GL-5. He just showed me the bottle and said buy this.
I live in SoCal, and my ZF shifts like butter, does not leak and is perfect.
So that is what I choose to use.
Lee