zf6 trans oil question
Thread Starter
Drifting
Joined: May 2005
Posts: 1,258
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From: springtown Texas
zf6 trans oil question
I bought a brand new zf6 blue tag trans to replace the 90,000 mile one in my 96. it came full of oil from GM. my question is should I run it with the oil that came in it or drain and fill with something better. like amsoil ? here it is.
Team Owner
Joined: Sep 2003
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I believe if your intention is to run something other than the OE fluid I'd do the change now. I've got a couple ZF's that I've never checked the fluid level in but I assumed they were shipped wet but maybe not full. Yours was full?
I won't start the debate over for lubricants, I've got enough OE for a good while and some to offer with the transmissions when I sell them.
I would run it in gear at idle for an extended period on stands and I don't know that there would be a preferred gear.
I won't start the debate over for lubricants, I've got enough OE for a good while and some to offer with the transmissions when I sell them.
I would run it in gear at idle for an extended period on stands and I don't know that there would be a preferred gear.
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
You should put in something different, like the Castrol fill. It won't do a better job, but it will make you feel better.
Team Owner
Joined: Sep 2003
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My thoughts were that for the price of "knowing" what is going in and knowing also that at some point I will likely need to make a change so it might as well be accomplished "NOW". The factory fill is likely 10+ years old. Does that maybe make sense that you might "just do it"?
Race Director
Joined: Sep 2001
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From: NEwhere Ohio
Im using the amsoil stuff and am having great luck.
I did not have any luck with the castrol bmw stuff. It was grinding gears and would not allow full rpm/throttle engagement. The gear shift lever would get jammed and not go into 2nd gear at wot.
I switched to gm syncromesh and all the problems went away
The bmw castrol stuff belongs in bmws, not corvette transmissions. I dont care what zfdoc thinks, it didnt work in my car.
I did not have any luck with the castrol bmw stuff. It was grinding gears and would not allow full rpm/throttle engagement. The gear shift lever would get jammed and not go into 2nd gear at wot.
I switched to gm syncromesh and all the problems went away
The bmw castrol stuff belongs in bmws, not corvette transmissions. I dont care what zfdoc thinks, it didnt work in my car.
Thread Starter
Drifting
Joined: May 2005
Posts: 1,258
Likes: 38
From: springtown Texas
didn't pull the plug on the side to check if it was full but when I removed the plastic cap that goes in the trans where the yoke goes to check the new yoke I just got, the oil in it was pouring out so there's plenty of oil in there. going to drain it and go with amsoil. what is the one I need called? is it synthetic?
If I remember right I paid @ $1500.00 I think for the new trans. it was still in the crate. it's been a few years. just putting it in now.
If I remember right I paid @ $1500.00 I think for the new trans. it was still in the crate. it's been a few years. just putting it in now.
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Suckin' gas, haulin' ass.
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From: Newport News Virginia
Le Mans Master
Joined: May 2004
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I believe if your intention is to run something other than the OE fluid I'd do the change now. I've got a couple ZF's that I've never checked the fluid level in but I assumed they were shipped wet but maybe not full. Yours was full?
I won't start the debate over for lubricants, I've got enough OE for a good while and some to offer with the transmissions when I sell them.
I would run it in gear at idle for an extended period on stands and I don't know that there would be a preferred gear.
I won't start the debate over for lubricants, I've got enough OE for a good while and some to offer with the transmissions when I sell them.
I would run it in gear at idle for an extended period on stands and I don't know that there would be a preferred gear.
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 110
From: Austin Texas
Im using the amsoil stuff and am having great luck.
I did not have any luck with the castrol bmw stuff. It was grinding gears and would not allow full rpm/throttle engagement. The gear shift lever would get jammed and not go into 2nd gear at wot.
I switched to gm syncromesh and all the problems went away
The bmw castrol stuff belongs in bmws, not corvette transmissions. I dont care what zfdoc thinks, it didnt work in my car.
I did not have any luck with the castrol bmw stuff. It was grinding gears and would not allow full rpm/throttle engagement. The gear shift lever would get jammed and not go into 2nd gear at wot.
I switched to gm syncromesh and all the problems went away
The bmw castrol stuff belongs in bmws, not corvette transmissions. I dont care what zfdoc thinks, it didnt work in my car.
ZF recommends the Castrol, and it works very well. If you were having problems then it isn't the fluid, it's your transmission. Changing the fluid is just putting a band-aid on the problem...it's still there and will only get worse over time.
Team Owner
Joined: Sep 2003
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actually... Bill is just quoting the MANUFACTURER.
ZF recommends the Castrol, and it works very well. If you were having problems then it isn't the fluid, it's your transmission. Changing the fluid is just putting a band-aid on the problem...it's still there and will only get worse over time.
ZF recommends the Castrol, and it works very well. If you were having problems then it isn't the fluid, it's your transmission. Changing the fluid is just putting a band-aid on the problem...it's still there and will only get worse over time.
Pro
Joined: Aug 2007
Posts: 668
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From: Austin TX
Well.. I totally respect a lot of your opinions on many subjects. But putting the BMW Castrol solved my issue of synchro grinding when hot. And shifts pretty good too. I don't know about WOT shifting. I don't do much of that.
Safety Car
Joined: Feb 2000
Posts: 4,564
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From: Austin Texas
Yes the Castrol is a "ZF spec'd" product and you certainly can't fault Bill. I've maintained that "frequency" might be much more important than maybe the product except that even some of the synthetic promoters "Royal Purple" comes to mind actual reference their engine oil spec product for OE fluid "interchange". RP - GM 1052931 it's suggested fill is HPS 10W-30.
BMW uses it in their "M"-spec engines, which is why you can go up to their parts counter and get it.
Team Owner
Joined: Aug 2000
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From: San Pedro CA
The key is does the oil handle shearing forces... not many oils can. And that is the key difference between engine oil and gear oil.
I have used the OEM, it's fine. I have used the Castrol TWS, and it's ok, too. I am currently using the Amsoil, and find it to be the best. Not by much, but better. It's also easier to get than the BMW fill. Not everyone has a BMW dealer, but there are Amsoil dealers crawling in about every gutter in every town...
I have used the OEM, it's fine. I have used the Castrol TWS, and it's ok, too. I am currently using the Amsoil, and find it to be the best. Not by much, but better. It's also easier to get than the BMW fill. Not everyone has a BMW dealer, but there are Amsoil dealers crawling in about every gutter in every town...
Team Owner
Joined: Sep 2003
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When someone such as RP has a likely quality spec transmission product BUT still recommends another from their line rather than "push/shove" with a comment "it's better" I believe it adds tremendously to their credibility.
Their OE product change is near the end of this PDF.
http://royalpurpleconsumer.com/asset...log_052113.pdf
Race Director
Joined: Sep 2001
Posts: 14,682
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From: NEwhere Ohio
i have since drained the syncromesh (to go to amsoil) and it was clear. No bronze flecks.
Last edited by dizwiz24; Feb 27, 2014 at 07:34 PM.
