ZF black and blue tags
Thread Starter
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
ZF black and blue tags
I had my 94 on the lift last weekend and now I am curious.
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
I had my 94 on the lift last weekend and now I am curious.
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
In his late 30's.
I often would look at all the Corvettes he had apart.
1984-1996 & 1997-2004.
It was AMAZING THE AMOUNT OF PARTS ON HAND.
Even more amazing was his vast knowledge of C4's and C5's.
Sort of like the Gordan Kilebrew of his generation.
They are actually good friends.
But Black Tag ZF's I understand from talking to Jason were for 1990-1995 ZR-1 cars.
The Blue Tag ZF's were for 1989-1996 Non ZR-1 DOHC powered cars.
I may be mistaken.
What ever trans they used in the ZR-1 cars were definite Heavy Duty Items.
Never heard of one failing in "Z" car unless it ran out of gear oil.
Brian
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
By the way, I am unsure why your ZF 6-speed has both the Black Tag and Blue Tags intact on it.
I recall the tags being production date coded.
That may help you figuring out what you really have.
ZR-1 Spec trans would nice to have.
Brian
I recall the tags being production date coded.
That may help you figuring out what you really have.
ZR-1 Spec trans would nice to have.
Brian
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
the blue tag was from mid '93 - '96.
Black tag units were made in West Germany, by ZF. By 1993, GM was making them under license in the USA.
There were a number of complaints about gear whine on the black tag units.
So the blue tags were "quieted down" by cutting the gears at a steeper angle than those in the black tag box.
The result is marginally weaker box
450 ft/lb rating for the black tag, vs. 400 ft/lb for a quieter but not quite as strong blue tag.
ZR1 had the same identical ZF6 trans; year for year
Only changes were input shaft length was different and a different bellhousing to suit the LT5
Last edited by rodj; Mar 4, 2011 at 03:13 AM.
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
The black tag was from '89 to mid '93,
the blue tag was from mid '93 - '96.
Black tag units were made in West Germany, by ZF. By 1993, GM was making them under license in the USA.
There were a number of complaints about gear whine on the black tag units.
So the blue tags were "quieted down" by cutting the gears at a steeper angle than those in the black tag box.
The result is marginally weaker box
450 ft/lb rating for the black tag, vs. 400 ft/lb for a quieter but not quite as strong blue tag.
ZR1 had the same identical ZF6 trans; year for year
Only changes were input shaft length was different and a different bellhousing to suit the LT5
the blue tag was from mid '93 - '96.
Black tag units were made in West Germany, by ZF. By 1993, GM was making them under license in the USA.
There were a number of complaints about gear whine on the black tag units.
So the blue tags were "quieted down" by cutting the gears at a steeper angle than those in the black tag box.
The result is marginally weaker box
450 ft/lb rating for the black tag, vs. 400 ft/lb for a quieter but not quite as strong blue tag.
ZR1 had the same identical ZF6 trans; year for year
Only changes were input shaft length was different and a different bellhousing to suit the LT5
Thanks for the clarification On Black ZF and Blue tag ZF's.
I will remember your lesson too.
Brian
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Could have been a dealer replacement when the car was under warranty?
THey dont always put new parts in, they have th right to put used/rebuilts if you read the fine print, at least with late models its that way not sure about the 90s.
THey dont always put new parts in, they have th right to put used/rebuilts if you read the fine print, at least with late models its that way not sure about the 90s.
Melting Slicks
Joined: May 2006
Posts: 3,303
Likes: 14
From: Lynn MA
hi so if you have a black tag out of a ZR1 and a black tag out of a non ZR1 sitting next to each other on the ground, the only way to identify at first glance as that the ZR1 will have a shorter input shaft?
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Team Owner
Joined: Sep 2003
Posts: 25,356
Likes: 2,729
There are only 2 input shafts, L98/LT1'LT4 share and the LT5 is by itself. The S6-40 was also used in the Lotus Carlton.
Melting Slicks
Joined: May 2006
Posts: 3,303
Likes: 14
From: Lynn MA
anyone have a measurement of the input shaft from say the face of the trans case to the end of the shaft where it slides into the pilot bearing? I am sure the NON ZR1 models are more common and I have seen some popping up at swap meets...my car is set up for a NON ZR1 6 speed, so if I trip across one, want to make sure I am getting the right one as a spare
thanks
thanks
Team Owner
Joined: Sep 2003
Posts: 25,356
Likes: 2,729
anyone have a measurement of the input shaft from say the face of the trans case to the end of the shaft where it slides into the pilot bearing? I am sure the NON ZR1 models are more common and I have seen some popping up at swap meets...my car is set up for a NON ZR1 6 speed, so if I trip across one, want to make sure I am getting the right one as a spare
thanks
thanks
190.5mm for the LT5 (7.5 in)
That's case to the tip of the input-shaft
Instructor
Joined: Mar 2019
Posts: 103
Likes: 11
From: Prague Czech Republic/Atlanta GA
I had my 94 on the lift last weekend and now I am curious.
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
The transmission has the normal black tag. Below the black tag is another smaller tag that says it was remanufactured. Below that tag is a blue ZF tag the same size as the black one. I forgot to take pictures and I am finished with the exhaust so it is down again and I can't take pictures for a while
I am not sure what all the tags mean. My guess is that it was a black tag transmission that was rebuilt by ZF. I am not sure if the blue tag means it was rebuilt with the blue tag internals or not.
Anyone have any ideas?
