Black Tag going into '94 Z

[YungEff]

Sup everyone,

I've removed the Blue Tag ZF-6 from my '94 ZR-1 and i've got a question. What is the easiest way to mate the Black Tag ZF6 to the '94 ZR-1, which is set up to accept a Blue Tag unit? I'm aware of the throwout bearing ID difference between the car year models.. Is changing the Throwout Bearing the only way to get the trans in? Or is there another option since I have both trans here? Just wanting to get some experienced answers. Thanks

YungEff

[Ccmano]

Sup everyone,

I've removed the Blue Tag ZF-6 from my '94 ZR-1 and i've got a question. What is the easiest way to mate the Black Tag ZF6 to the '94 ZR-1, which is set up to accept a Blue Tag unit? I'm aware of the throwout bearing ID difference between the car year models.. Is changing the Throwout Bearing the only way to get the trans in? Or is there another option since I have both trans here? Just wanting to get some experienced answers. Thanks

YungEff

Its just the input shaft diameter. So yes, just the Throwout bearing for the install. However the Black label uses a lockout lift ring for reverse. You will need an early version shift lever with the lockout lift ring to engage reverse. The ring uses Allen screws that lock the ring to a shaft that runs in the center of the shift lever. Once tightened you lift the ring with your fingers as you shift into reverse. The shaft is lifted and allows reverse to engage. You will also find that the VSS electronic connectors are different. Just swap the VSS unit from the blue tag into the black tag so connectors match your harness. You will also notice that the trans will be louder in low gears, some even have a slight growl, under 2000 rpm due to the slightly straighter cut of the gears.
H
:cheers:

[Dynomite]

A Black label trans with short shifter rebuilt by ZFdoc installed in 95' (No Lift Ring) 👍👍


Post 241 - Rebuilt Black Label Transmission Installed and New Driveshaft U-Joints (https://www.corvetteforum.com/forums/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-13.html#post1592505462)

[tccrab]

Swap the VSS from the Blue tag to the Black tag.
Obviously the throwout bearing is different.
You'll need a early model shift boot with the reverse lockout ring, it's attached to the boot itself.


I put a '95 Blue tag in my '90 after the third gear synchros went out on my black tag. I found it more economical to buy a factory rebuilt transmission than rebuild my black tag. No reverse lockout ring, and I bought a ZR1 labeled T-Handle shift knob from a forum member who makes them, which I prefer over the stock shift knob.


The blue label is much quieter transmission, but does make about the same amount of growling in neutral with the clutch out as the Black tag did.



'Crabs

[Paul Workman]

The obvious question is: WHY do you ask? There are pros and cons either way.

Excerpt from an article delivered by Marc Haibeck at Bowling green (date unknown by me)

The serial and model tags are black up to about 1993 ½. They are blue from that point forward.
Black tags units were manufactured in West Germany. The blue tag units were manufactured in Vernon Hills Illinois. There is no clear correlation for tag color and torque capacity. The model number listed on the tag specifies the torque capacity.

The entire article:

[YungEff]

Thanks for the .PDF Paul, and thanks everyone for the responses. I was mostly wondering if the input shaft guide tube could be swapped from the blue to the black tag unit. That should allow the black tag to work with my original '94 throwout bearing, but i'm guessing it's not that simple (correct me if i'm wrong).
Anyway, i did order the '89-93 throwout bearing but I haven't Installed it. I'll be getting back to working on the car this week.

YungEff

[WVZR-1]

A '94 if original would be a 'black tag' and have a lift ring i believe. 3 I've seen were. Is the 081 'blue'? I've no idea. If you've a known good 'maybe' OE release bearing swapping the guide tube I'd think deserves some consideration.

If the 'black tag' is a '91+ you shouldn't need to be concerned about the VSS. If the 'black tag' is a '90 it will have a center connector and it would be wise to swap yours.

I'd be interested in a snapshot of your service tag on the take out!

[YungEff]

Actually my ZR-1 is a '94 model with an original blue tag. However I did speak with Bill and he told me that I could swap the guide tube from my blue tag to my black tag, which will allow me to leave the original throwout bearing in.

So Im gonna do that and then install the black tag. Thanks again though to everyone who responded.

YungEff

[WVZR-1]

Actually my ZR-1 is a '94 model with an original blue tag. However I did speak with Bill and he told me that I could swap the guide tube from my blue tag to my black tag, which will allow me to leave the original throwout bearing in.

So Im gonna do that and then install the black tag. Thanks again though to everyone who responded.

YungEff


How about a snapshot of the 'tag'!!!

[YungEff]

Sure, here is a pic of the blue tag ZF6 I removed from my '94.

[WVZR-1]

Sure, here is a pic of the blue tag ZF6 I removed from my '94.


Thanks!! Does have a lift ring on the shifter! Correct?

[YungEff]

It's Actually got a hurst short-throw shifter so it does not have a lift ring.

[WARP TEN]

It's Actually got a hurst short-throw shifter so it does not have a lift ring.

When I had Marc install a Hurst shifter on my '93 back in about 1995 (because I hated the lift ring) it seemed to have enough spring pressure when pushing it sideways that I did not feel any further safeguard was necessary. I never missed a 4-5 shift and went into reverse.--Bob

[Paul Workman]

When I had Marc install a Hurst shifter on my '93 back in about 1995 (because I hated the lift ring) it seemed to have enough spring pressure when pushing it sideways that I did not feel any further safeguard was necessary. I never missed a 4-5 shift and went into reverse.--Bob

Well, actually I think you meant a 5-6 shift...is where one would be most likely to miss and go into reverse. But, maybe a 2-3 shift too w/o a lift ring would (technically) avail an accidental 2- reverse shift.

However, Ami's Hurst shifter is way more positive that stock. I have accidentally done a 2-5 :mad: instead of hitting 3rd on several speed shift attempts on occasion with my stock shifter.

[WARP TEN]

Well, actually I think you meant a 5-6 shift...is where one would be most likely to miss and go into reverse. But, maybe a 2-3 shift too w/o a lift ring would (technically) avail an accidental 2- reverse shift.

However, Ami's Hurst shifter is way more positive that stock. I have accidentally done a 2-5 :mad: instead of hitting 3rd on several speed shift attempts on occasion with my stock shifter.

Yes Paul you are right. 5 to 6. Forgot reverse was down and away. So easy to do when you have graduated to an automatic....;). In any case I do recall getting slightly hung up in the side-to-side reverse gate once when shifting from 4 to 5, but not actually going into reverse (which would be in the other direction as you note). I also had Hursts in both cars and their spring detent was certainly sufficient to keep me out of reverse except when I wanted to
go there.--Bob

[Corvette95]

Old thread..but does anyone have step by step procedures and pictures on swapping the guide tube (and related parts etc) from a black label transmission to a blue label transmission?

[Ccmano]

Old thread..but does anyone have step by step procedures and pictures on swapping the guide tube (and related parts etc) from a black label transmission to a blue label transmission?

Why? Just use the later Throwout bearing...
I'm running a blue label in my 90', works just fine that way.
H
:cheers:

[Corvette95]

Well, that is the other option. I was trying to prevent issues with getting a new pilot bearing seated just right and hoping to get a good (not China) throw out bearing. I don?t know which is the better way. I am open to suggestions in the best course of action . I know what throw out bearing to use, what pilot bearing do I use if I went that route and what style ? I originally thought swapping the sleeve would be easier and less risky for noise. Anything to swap with fork? Help me make a good decision here. Thanks! I?ll be honest , in all my research I didn?t not catch the guide sleeve until I COMPLETELY installed the blue tag to completion and mean hydraulics hooked up and bleed , c beam in...done. I luckily have not started the engine , I found this by accident as I was researching early model 90 Voss sensors and found one small thread mentioning the tube... oh well, a blessing if I look at it right because I caught it before it was started. I can?t sleep now thinking of redoing the job again on my back on jack stands without a proper trans jack! I researched the swap extensively, maybe it would make a good solutions sticky?

[Ccmano]

Yeah that would not have worked. Don't drive the car that way. It would destroy the clutch assembly and probably the input shaft in short order. Switching the Throwout bearing is the only thing you have to do because of the smaller diameter input shaft on the blue label. Everything else is the same, fork included.
I'm sure someone here might have a TO bearing stashed. Your old one could even be traded or sold. The rarely go bad. Put up an ad.

If I'm not mistaken the Centerforce TO bearing is made in Brazil not China. While not the same quality as the originals I believe it's serviceable for a stock HP engine. Here's one advertised on EBay.
https://www.ebay.com/itm/224102665349

Good thing you caught that.

Oh and don't sweat the pilot bearing install. It's a simple install, it rests against a machined stop in the end of the crankshaft. The only thing you can really do wrong is not put it in deep enough. If your concerned simply measure the depth of the old one before you remove it and install the new one to the same depth.
H
:cheers:

[Corvette95]

Yeah that would not have worked. Don't drive the car that way. It would destroy the clutch assembly and probably the input shaft in short order. Switching the Throwout bearing is the only thing you have to do because of the smaller diameter input shaft on the blue label. Everything else is the same, fork included.
I'm sure someone here might have a TO bearing stashed. Your old one could even be traded or sold. The rarely go bad. Put up an ad.

If I'm not mistaken the Centerforce TO bearing is made in Brazil not China. While not the same quality as the originals I believe it's serviceable for a stock HP engine. Here's one advertised on EBay.
https://www.ebay.com/itm/224102665349

Good thing you caught that.

Oh and don't sweat the pilot bearing install. It's a simple install, it rests against a machined stop in the end of the crankshaft. The only thing you can really do wrong is not put it in deep enough. If your concerned simply measure the depth of the old one before you remove it and install the new one to the same depth.
H
:cheers:

Thanks...the car never even got started before I found the problem...it was research on the different exhaust hanger bracket for the different tail shaft that I found by luck the TO bearing difference. I ordered a roller bearing tpe pilot, that is what Marc H recommends, I understand Bill B recommends the fluted type...which are you using?

[Ccmano]

When it comes to all things ZF I go with Bills recommendations. I use the fluted bronze. Haibeck is not wrong. The latest TSB from GM on the subject I believe recommended the roller type. Either will be just fine. Use what you ordered. I assume you read this?
http://zr1specialist.com/HAT%20Web/articles/Clutch%20Replacement%20Options%20in%202019.pdf
H
:cheers:

[Dynomite]

When it comes to all things ZF I go with Bills recommendations. I use the fluted bronze. Haibeck is not wrong. The latest TSB from GM on the subject I believe recommended the roller type. I either will be just fine. Use what you ordered. I assume you read this?
http://zr1specialist.com/HAT%20Web/articles/Clutch%20Replacement%20Options%20in%202019.pdf
H
:cheers:

Pilot Bearing (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-2.html#post1581460766)

It has been suggrested to NOT use the needle bearing as it is a needle type bearing designed for 6.2L diesel trucks which have a limit of only 4,000-4,500 rpms. The theory is that those little needles will turn at over 7,000 rpms. It has therefore been suggested the ideal bushing replacement is a bronze type with three grooves (or flutes) spiraled inside and is available under the GM part number 10125896.

This really only applies to drag racing where you drop the clutch at high rpms. At all other times the RELATIVE rpm difference between the transmission spline and the flywheel are low and much less than 4,000 rpm. The needle bearing pilot would be the best choice for most applications excluding drag racing.

When I install the needle pilot bearing I pack the bearing with greese :thumbsup:

[A26B]

I made a cut-away bellhousing and acquired a case with input shaft & both large & small guide tubes, to develop the RAM Clutches applied to several different combinations of flywheels.

You can see that there is no way the face of the pilot bushing is going to contact the input shaft shoulder at the splines.

These photos came from that set up.

https://cdn10.bigcommerce.com/s-nkg90o/products/879/images/2059/Pilot_Bushing_Relative_Position-A__08498.1484268600.1280.1280.jpg?c=2

https://cdn10.bigcommerce.com/s-nkg90o/products/879/images/2060/Pilot_Bushing_Relative_Position-B__59922.1484268600.1280.1280.jpg?c=2

[Corvette95]

Thanks Jerry, your site is a wealth of information, and you provide it for free...THANKS! I know these types of jobs are simple for most, other than the last LT5 swap (that I did on floor on stands) back when I had my shops with lifts, I had to do my LT1 5 TIMES because I kept getting chatter, that was of course using a spec clutch, I am reusing all current clutch and pressure plates, going to absolutely follow torque loosening sequence, mark the clutch and flywheel and torque then in sequence and hope for not chatter. I see different recommendation on pilot bearing to lube or not to lube?

[Dynomite]

I see different recommendation on pilot bearing to lube or not to lube?

Depends on which type of Pilot Bearing you select (Needle Bearing or Oil-Lite Bearing).

What causes a Oil-Lite pilot bushing to fail? Grease applied to the inside diameter surface of an oil-lite (oil saturated) pilot bushing is the number one cause for Oil-Lite pilot bushing failure. Grease applied in a Oil-Lite pilot bushing eventually dries up and clogs the otherwise normally self-oiling pours of the bushing.

This does NOT apply to a needle Bearing Pilot Bushing which like any needle or ball bearing needs lubrication.

[Ccmano]

What causes a Oil-Lite pilot bushing to fail? Grease applied to the inside diameter surface of an oil-lite (oil saturated) pilot bushing is the number one cause for pilot bushing failure. Grease applied in a Oil-Lite pilot bushing eventually dries up and clogs the otherwise normally self-oiling pours of the bushing.

This does NOT apply to a needle Bearing Pilot Bushing which like any needle or ball bearing needs lubrication.

Absolutely right! Lube the needle (roller) bearing, do not under any circumstances lube the bronze (Oil-lite) bearings, fluted or plain.
H
:cheers:

[wfot]

One thing I found was that the early throw out bearings are WAY more plentiful than the blue tags. black tags numbered in the 4 thousands and the blue tags were barley 1500 made I believable. And I believe someone bought up all of the remaining blue tag GM/Good throw outs and they were like 200+ years ago - my personal rant grrrrr

Also agree about the cheap china bearings break after a few thousand miles (read this) and most people use original bearings with moderate mileage as they are pretty tough to beat.

but the biggest thing for me was that it is near impossible to find a good quality blue tag throw out. If I were you keep the black tag in tact and use a more plentiful and not china throwout bearing.

my 2 for today
John

[Corvette95]

When I installed the blue tag transmission, it was in conjunction with new motor mounts so they were not bolted on the bottom allowing me to raise the motor, I have read in solutions one method is to loosen motor mounts, other says it is not necessary. Well I have the motor mounts shimmed and placed exactly where I want them to give me header clearance to steering shaft and used Bill B c beam plates when I reinstalled the c beam and I checked the clearance, so my question is do I need to unbolt the two bottom bolts of the motor mounts to raise engine ? If I can do it with them left tight I will since it took a bit of time to get perfect adjustment. Thanks

[Corvette95]

Do I need to pull the flywheel to replace pilot bearing since I am not replacing clutch?

[Jagdpanzer]

No


Sent from my iPhone using ZR-1 Net Registry (http://r.tapatalk.com/byo?rid=90383)

[wfot]

you will need to remove the pressure plate and disc and have the alignment tool to put everything back together...

[Ccmano]

No


Sent from my iPhone using ZR-1 Net Registry (http://r.tapatalk.com/byo?rid=90383)

Agreed, the pilot bearing is accessible without removing the flywheel.
H
:cheers:
https://farm66.staticflickr.com/65535/50783966238_b808e5e3ce_c.jpg (https://flic.kr/p/2knB6SN)

[Corvette95]

Pilot bearing is out. I am done for the year. Thanks for the help. I do have an alignment tool to put it all back in..waiting for a shipment from Jerry's. I am a little concerned with getting the fork back on the throw out bearing as I didn't remove the 6mm cover screw.

[wfot]

hummm, the screw that holds the stud in?
can you post a pic of what you are concerned about?
J

[Corvette95]

I did not loosen the shift fork or ball stud, it was frozen, I pushed the fork off the throw out bearing and twisted the bellhousing to remove the housing. I am concern with getting the fork back on the throw out bearing... in solutions there is a list of installation tips #5 says there is a trick to get the throw out bearing seated properly but provided no detail of the "trick".

INSTALLATION
1. Lubricate the new pilot bearing.
2. Remember to torque the pressure plate bolts uniformly in steps.
3. Remember to insert clutch plate alignment tool with clutch depressed before trying to install transmission.
4. It also helps if someone presses the clutch as you insert transmission releasing the new clutch plate for better alignment with transmission spline.
5. When you attach bell housing there is a trick to get the throwout bearing mating with the yoke properly.
6. I already mentioned marking the drive shaft and re-installing as it was removed from rear differential yoke.
7. Remember torque on front and rear C4 Beam Plate bolts 59 ft-lbs on rear two bolts and 37 ft-lbs on front two bolts.
8. Use alignment tabs provided by ZFDoc with C4 Beam Plates which align the "C" frame properly with frame just near the shifter assembly.
9. Leave 4 original washers on the rear (Differential) off the bolts. I installed 2 of the 4 original washers on the front (Transmission) bolts as they were originally.
10. The Tranmsmission C4 Beam Plate beveled corner faces toward the front of the transmission.

[Pete]

No need to take the fork out.
The fork slides back and locks in place on the bell housing once you bolt bell housing on align the straights of the bearing to the fork and with a screw driver thru the slave cylinder hole push fork towards the bearing and fork will slide right over the bearing.

Pete

[Ccmano]

hummm, the screw that holds the stud in?
can you post a pic of what you are concerned about?
J

You don't have to remove the stud or the cover. Just install the TO bearing on the pressure plate. Cleanup, lube and install the fork on the stud. Then when you install the bellhousing with the fork, engage the fork on the TO bearing as you install the bellhousing. It takes some rotating of the bellhousing to get the fork engaged with the TO but it all comes together. Once you have the fork engaged rotate the bellhousing into place and bolt her up. Hope that's reasonably clear.
H
:cheers:

[Corvette95]

Thanks, I am done until the pilot bearing gets here from Jerry. I have it reasonably clear in my head now, thanks. I am sure I will be back in the New Year with more assembly questions.

[Dynomite]

I did not loosen the shift fork or ball stud, it was frozen, I pushed the fork off the throw out bearing and twisted the bellhousing to remove the housing. I am concern with getting the fork back on the throw out bearing... in solutions there is a list of installation tips #5 says there is a trick to get the throw out bearing seated properly but provided no detail of the "trick".

INSTALLATION
1. Lubricate the new pilot bearing.
2. Remember to torque the pressure plate bolts uniformly in steps.
3. Remember to insert clutch plate alignment tool with clutch depressed before trying to install transmission.
4. It also helps if someone presses the clutch as you insert transmission releasing the new clutch plate for better alignment with transmission spline.
5. When you attach bell housing there is a trick to get the throwout bearing mating with the yoke properly.
The Clutch Fork can be slid to the drivers side of the Bell Housing (elongated hole with spring clip) once the transmission is removed. This will disengage the Clutch Fork from the Throwout Bearing for Bell Housing removal and installation.
6. I already mentioned marking the drive shaft and re-installing as it was removed from rear differential yoke.
7. Remember torque on front and rear C4 Beam Plate bolts 59 ft-lbs on rear two bolts and 37 ft-lbs on front two bolts.
8. Use alignment tabs provided by ZFDoc with C4 Beam Plates which align the "C" frame properly with frame just near the shifter assembly.
9. Leave 4 original washers on the rear (Differential) off the bolts. I installed 2 of the 4 original washers on the front (Transmission) bolts as they were originally.
10. The Tranmsmission C4 Beam Plate beveled corner faces toward the front of the transmission.

Edited :thumbsup:

Pete alluded to this in above post #36 :cheers:

[Corvette95]

So, I am using the roller type pilot that gets greased. Do I grease the outer shaft where the bearing rides or just the inner rollers of the pilot? Thx

[Dynomite]

So, I am using the roller type pilot that gets greased. Do I grease the outer shaft where the bearing rides or just the inner rollers of the pilot? Thx

Pack the inner rollers as you would pack a wheel bearing :cheers:
I think the Pilot bearing (needle bearing) comes pretty well packed with grease already :thumbsup:

[Corvette95]

As a PSA the 94-96 manual leather shifts boots have been out of stock everywhere, new shipment just came in at the end of December, I got mine last Friday, got the transmission install finished yesterday and went to swap shift boot on my shift plate and mine at least (probable whole run) came in with the boot glued to the metal frame that attaches to the bottom of the shift plate backwards... can't shift to forward gears, I was lucky enough, not that it is that big of a job to quickly notice this, I removed the leather from the supplied metal mounting plate and turned it around and glued it and left it in small clamps overnight and installed it today....now it is right. Usually when this happens there is usually one run of production that goes to all the Corvette parts sellers

[Corvette95]

Short test drive to check transmission tonight, header only waiting on a few small parts for custom exhaust. Man was it loud but with the new Prothane Motor Mounts, NOS Blue Tag, new pilot bearing and throw out bearing new clutch master and slave...ZERO , actually less than zero play or movement in drivetrain or shifter, I have stock PROM in it as I am awaiting my updated PROM from Haibeck any day, but it breaks the tires loose in third gear with just the headers. WOW! I wasn't in a residential zone but the exhaust sound vibrated the console. It was cool and best of all transmission install successful thanks for all the transmission help!

[wfot]

curious about the prothane motor mounts. what part number is it? any pics?

thanks

John

[Corvette95]

curious about the prothane motor mounts. what part number is it? any pics?

thanks

John

The Prothane mounts are solid billet aluminum with a rubber cushion. I do have pics of the entire restoration I will be posting soon. I have pics of the mounts with my custom heat shields.. Will try to get a pic posted.

[Ccmano]

The Prothane mounts are solid billet aluminum with a rubber cushion. I do have pics of the entire restoration I will be posting soon. I have pics of the mounts with my custom heat shields.. Will try to get a pic posted.

I'm curious why you went with those. It's more of a race car thing. They must cause a lot of engine noise and vibration.
H
:cheers:

[Corvette95]

I'm curious why you went with those. It's more of a race car thing. They must cause a lot of engine noise and vibration.
H
:cheers:

Mainly because of heat , the can stand up to header temperatures plus it gives more room to O2 connectors and I made heat shields for them to look like OEM. I also like the more connected feeling and less weight transfer. The have rubber dampers on the bottom. I think they will be fine. When I get the new exhaust on and drive , I will be issuing a thorough report on a lot of items.