1992 ZR1 - Transmission questions - ZR-1 Net Registry Forums

ZBot · 3 Weeks Ago

Hi everyone, I'm a prospective buyer looking at a 1992 ZR1 with 110,000 miles. It needs some work to get the secondaries working and general freshening up to get the maintenance up to date. I'm fine with doing my own work and am up for a project.

One thing I have questions about is the transmission. Are these units good to handle higher mileage like this? Or should I be budgeting a rebuild soon?

Any other tips and advice is appreciated for a possible first time owner.

Thanks!

dredgeguy · 3 Weeks Ago

I have a 92 with just about 117,000 miles with the original transmission and clutch. Clutch release point is higher than at 50,000 miles when I got it but no slipping or other issues so far. At least the one you are looking at was driven, if you have any maintenance records should be more than fine. What part of the country?

ZBot · 3 Weeks Ago

Got it, I appreciate the info! It's in Colorado.

tccrab · 3 Weeks Ago

For the most part the ZF6 is a really great transmission.
There are many out there still going strong after 30+ years.
They can handle ungodly amounts of HP and Torque.
They may not be a M22 Rockcrusher, but they are in the same league.
They do have a few tiny weak spots.
Speed shifting and missing gears can and do wipe out syncromesh gear teeth. Don't ask me how i know this. What I will tell you is that its expensive to fix after you've done it.
And then there's an issue of "mis-use" of 6th gear.
Let's say you have a burning desire to see close to 200mph.
You'd best not make the attempt in 6th gear. Wind it up to 7500 rpm in 5th, but don't do the same in 6th on an unmodified ZF6.
There's an internal oiling issue that will bite you very hard. 6th was designed to maximize MPG at freeway speeds, not set records at the Salt Flats.
Good news is that Bill B. "The ZFDoc" at ZR51 Performance has the answers for these issues.

So, test drive the car.
Bang through 1st, 2nd and 3rd.
No need to hit the rev limiter, but exercise the gears.
If it shifts smooth and firm, you probably wont need the ZFDoc.
You're still going to buy the car.
It's a ZR-1 after all.

Once you've discovered permagrin, you are hooked.

AlbanyBrian · 2 Weeks Ago

As others have offered the ZF6 is good and very durable. If it shifts fine probably the only thing to plan for is a fluid change.
Brian

3 Weeks Ago	#1
ZBot Join Date: Jan 2024 Location: USA Posts: 2	1992 ZR1 - Transmission questions Hi everyone, I'm a prospective buyer looking at a 1992 ZR1 with 110,000 miles. It needs some work to get the secondaries working and general freshening up to get the maintenance up to date. I'm fine with doing my own work and am up for a project. One thing I have questions about is the transmission. Are these units good to handle higher mileage like this? Or should I be budgeting a rebuild soon? Any other tips and advice is appreciated for a possible first time owner. Thanks!

3 Weeks Ago	#2
dredgeguy Join Date: Aug 2012 Location: Ellicott City, MD Posts: 1,714	Re: 1992 ZR1 - Transmission questions I have a 92 with just about 117,000 miles with the original transmission and clutch. Clutch release point is higher than at 50,000 miles when I got it but no slipping or other issues so far. At least the one you are looking at was driven, if you have any maintenance records should be more than fine. What part of the country? __________________ Charlie __________ Dredgeguy WAZOO Member 1992 Bright Red/Black ZR1 #246 Dana 4:10 gears Polished LT5 by Haibeck Polished Fikse FM5's with Michelin Pilot Sport 2 Stainless Works headers and cats with Corsa

3 Weeks Ago	#3
ZBot Join Date: Jan 2024 Location: USA Posts: 2	Re: 1992 ZR1 - Transmission questions Got it, I appreciate the info! It's in Colorado.

3 Weeks Ago	#4
tccrab Join Date: Oct 2004 Location: Folsom CA Posts: 1,655	Re: 1992 ZR1 - Transmission questions For the most part the ZF6 is a really great transmission. There are many out there still going strong after 30+ years. They can handle ungodly amounts of HP and Torque. They may not be a M22 Rockcrusher, but they are in the same league. They do have a few tiny weak spots. Speed shifting and missing gears can and do wipe out syncromesh gear teeth. Don't ask me how i know this. What I will tell you is that its expensive to fix after you've done it. And then there's an issue of "mis-use" of 6th gear. Let's say you have a burning desire to see close to 200mph. You'd best not make the attempt in 6th gear. Wind it up to 7500 rpm in 5th, but don't do the same in 6th on an unmodified ZF6. There's an internal oiling issue that will bite you very hard. 6th was designed to maximize MPG at freeway speeds, not set records at the Salt Flats. Good news is that Bill B. "The ZFDoc" at ZR51 Performance has the answers for these issues. So, test drive the car. Bang through 1st, 2nd and 3rd. No need to hit the rev limiter, but exercise the gears. If it shifts smooth and firm, you probably wont need the ZFDoc. You're still going to buy the car. It's a ZR-1 after all. Once you've discovered permagrin, you are hooked. __________________ TomC '90ZR1 #792 Honorary Pirate [B]If it ain't FUN, you're doing something terribly WRONG. [/B]

2 Weeks Ago	#5
AlbanyBrian Join Date: Feb 2023 Location: Albany, Oregon Posts: 37	Re: 1992 ZR1 - Transmission questions As others have offered the ZF6 is good and very durable. If it shifts fine probably the only thing to plan for is a fluid change. Brian __________________ 1993 ZR-1, #135, cool car 2008 Z06, fun car 1985 RIP, was a fun project/track car