Changed fluid in ZF-6 now having shifting problems when cold
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Joined: Jul 2000
Posts: 83
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From: Victoria, BC
Changed fluid in ZF-6 now having shifting problems when cold
Hi, had my trans fluid changed as per the ZF Transmission Recommended tech tip using GM Part# 1052931 this last monday. I checked with my GM sales rep, and he says that is the correct part number for my tranny, although his book only goes back to 1990. I believe this tranny is the same for 89-96.
I started having problems with the tranny shifting into second when driving the car for the first time yesterday morning. This morning I had to pull over cause it wouldn't go into second gear at all. It is pretty cold here about 0 degrees farenheight, and not sure if this is contributing to the problem, but everything was fine before the fluid was changed. Once the car has been driven for a few blocks, and warms up it is fine. When the car is up to temp the trans shifts like butter.
I have a few questions:
- anyone noticed any shifting problems when the ZF-6 is cold?
- is an additive required when this fluid is changed?
Anyone had this problem, and if so how did you fix it?
Thanks
I started having problems with the tranny shifting into second when driving the car for the first time yesterday morning. This morning I had to pull over cause it wouldn't go into second gear at all. It is pretty cold here about 0 degrees farenheight, and not sure if this is contributing to the problem, but everything was fine before the fluid was changed. Once the car has been driven for a few blocks, and warms up it is fine. When the car is up to temp the trans shifts like butter.
I have a few questions:
- anyone noticed any shifting problems when the ZF-6 is cold?
- is an additive required when this fluid is changed?
Anyone had this problem, and if so how did you fix it?
Thanks
Pro
Joined: Nov 2002
Posts: 513
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From: Maple Grove MN
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
That is the correct GM part # for the ZF fluid and there is no additive. Sounds to me like it is a cold weather issue, I think transmissions are generally a bit cranky in the cold. When I changed my fluid I used the Castrol stuff (the other fluid recommended by ZF) but I have never driven mine in cold weather.
Drifting
Joined: May 2003
Posts: 1,979
Likes: 48
From: Lakeport CA
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
Doesn't the ZF trans guy in Az say to use the Castrol that is spec'd for BMW trans or something like that? Go here to check out his site. I just installed my trans last night after a full rebuild & shifter shorten job.
http://www.zfdoc.com
http://www.zfdoc.com
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
Re: Changed fluid in ZF-6 now having shifting problems when cold (Trog)
Doesn't the ZF trans guy in Az say to use the Castrol that is spec'd for BMW trans or something like that? Go here to check out his site. I just installed my trans last night after a full rebuild & shifter shorten job.
http://www.zfdoc.com
http://www.zfdoc.com
Catrol TWS 10-60. You can get it only at a BMW dealer, at least as far as the good ole US of A is concerned. Donno about the Great White North.
Heel & Toe
Joined: Oct 2003
Posts: 15
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From: houston tx
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
I had the same symptoms a few weeks ago, and I was contemplating changing out the trans fluid, but before I did it, the problem got worse--turns out there was a leak in my clutch slave cylinder, and most of the fluid had drained out. I replaced the master and slave cylinders last weekend, and it shifts perfectly now.
I can't explain how warming up the car made it easier to shift with a leaky clutch system--but I don't think it could be a coincidence that the leak occurred after the cold shifting problem. You may want to check your clutch hydraulics.
I can't explain how warming up the car made it easier to shift with a leaky clutch system--but I don't think it could be a coincidence that the leak occurred after the cold shifting problem. You may want to check your clutch hydraulics.
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Joined: Jul 2000
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From: Victoria, BC
Re: Changed fluid in ZF-6 now having shifting problems when cold (spress3)
Did you have a problem getting it out of gear, or into gear? I am confused how a hydraulic problem with the clutch could cause that. Could you enlighten me ??
thanks
thanks
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
Mine shifts "notchier" when it's cold, especially in third gear. It almost feels like a double-step notch shifting to 3rd and sometimes to 2nd and 4th. When warm it feels much better. It kind of worries me a little but I feel better hearing from others that feel the same "notchy" shifts when cold.
My clutch is A-Ok, just replaced the fuild and bled earlier this year. In neutral you can hear the transmission stop spinning when you press the clutch so it's definitely disengaging as it should be. Clutch disk and PP was replaced this spring, Castrol 10w60 oil in the tranny this spring as well.
:steering:
My clutch is A-Ok, just replaced the fuild and bled earlier this year. In neutral you can hear the transmission stop spinning when you press the clutch so it's definitely disengaging as it should be. Clutch disk and PP was replaced this spring, Castrol 10w60 oil in the tranny this spring as well.
:steering:
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Le Mans Master
Joined: Jan 2000
Posts: 6,376
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From: Traverse City MI
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
When the clutch does not release fully (because of faulty hydralics) the internals on the transmission make it hard to shift, and you cause tons of wear and tear on the trans.
Try this. Start the car first thing in the morning and press the cluth to the floor and hold it there. If you can shift into 1st and then over to reverse and back to 1st again smoothly (should not catch at all) then your clutch is probably releasing properly.
Try this. Start the car first thing in the morning and press the cluth to the floor and hold it there. If you can shift into 1st and then over to reverse and back to 1st again smoothly (should not catch at all) then your clutch is probably releasing properly.
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Joined: Jul 2000
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From: Victoria, BC
Re: Changed fluid in ZF-6 now having shifting problems when cold (spress3)
Ok, this may be an obvious question, but I don't want to break anything. I cannot get the cap off the slave resevoir. I tried turning counterclockwise, and it doesn't move. Tried pulling off no dice. I don't want to force it too much as the master is all plastic. What's the trick to get the cap off.
Also the fluid level was at the add mark. So a bit low, but I would assume that it would still work ok, but I don't know how fussy this unit is..
Also the fluid level was at the add mark. So a bit low, but I would assume that it would still work ok, but I don't know how fussy this unit is..
Le Mans Master
Joined: Jan 2000
Posts: 6,376
Likes: 21
From: Traverse City MI
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
It twists off, counterclockwise. May have to get a wrench on it to get it off. Also, move the ECM if it's in the way. Once you have the cap off, suck the old fluid out wipe it out with a clean towel and put in fresh fluid.
Drifting
Joined: Jun 2000
Posts: 1,955
Likes: 2
Re: Changed fluid in ZF-6 now having shifting problems when cold (Aaron71771)
I flushed and bled my master and slave over the weekend. It helped with the grind I get going into second at high RPM but didn't completely eliminate it. I have the BMW fluid at home, will probably change it this weekend.
I am also going to try the clutch 1-R-1 check. My fluid was really nasty so the master or slave may be getting bad.
Jeff
I am also going to try the clutch 1-R-1 check. My fluid was really nasty so the master or slave may be getting bad.
Jeff
Race Director
Joined: Oct 2002
Posts: 10,864
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From: Southern CA
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
I think you push down on the cap & twist (like a rad cap). Also loosen & swing the computer out of the way first.
Race Director
Joined: Oct 2002
Posts: 10,864
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From: Southern CA
Re: Changed fluid in ZF-6 now having shifting problems when cold (chamilton)
Castrol may be better than the gm stuff for cold climates. The gm is NOT synthetic. The castrol MAY be synthetic - not positive.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
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From: NS
Re: Changed fluid in ZF-6 now having shifting problems when cold (froggy47)
The Castrol stuff is 100% synthetic, and it cost me $20.00+ Canadian dollars for 1 litre from the local BMW dealer. Apparently this is also engine oil for the little Z3 or Z4 roadster.
Burning Brakes
Joined: Dec 2001
Posts: 777
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From: Fort Worth Texas
Re: Changed fluid in ZF-6 now having shifting problems when cold (Atok)
The BMW product is thinner and warms up sooner and being a thinner lube it will help in COLD weather, but I would use a different product in the HOT summers (REALLY HOT in TEXAS) Red Line has a Full synthetic manual formula that has the GL-4 rating and is SAE rated 75w/80w API and SAE 30 and 10w30 rating. Go to Red Line`s web site and read how different viscosities of lubricants react to useage and extreem temptures and just OFTEN we need to change the trans fluids. Years ago ZF did not push a certain brand just a GL-4 API Gear oil that had a certain viscosity. I was thinking of useing the BMW lube in the winter and Red Lines in the summer.
Let us know how the BMW lube works.
Regards, Louis
1996 LT4 ZF 6 Coupe :chevy
Let us know how the BMW lube works.
Regards, Louis
1996 LT4 ZF 6 Coupe :chevy
