85 4+3 really that bad?
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Joined: Jun 2007
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From: Hatfield/Williamsport Pa
85 4+3 really that bad?
I'm going to look at a 40k mile 85 corvette tomorrow morning. It's got the 4+3 in it. I was at a local car show today and asked around for people's opnions about the car. It seems that everyone is warning me about the 4+3 and not to go anywhere near the car. Is the transmission really that aweful? What should I look into? Any other tips and info would be great.
Thanks
Red1992V6Rs
Thanks
Red1992V6Rs
Le Mans Master
Joined: May 2004
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The automatic section of the gearbox is what gives people fits. If you go to check it out and the owner can assure you that the trans has been serviced on an excellent schedule, then there shouldn't be a problem.
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From: Tucson Az
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From: Cincinnati, Oh USA
I drive my 87 4+3 everyday, it has 223k on it. At about 150k the overdrive took a dump and I got it repaired for $650 and it has been fine since. The only thing I can tell you NOT to do is to roll the car and pop the clutch to start it, that will damage the OD. I like my 4+3!
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I bought my 85 a couple of years ago with 45,000 miles. The 4 plus 3 had been rebuilt at 30,000 miles. Apparently the Chevy dealership that rebuilt it did not do it properly. I had problems right away. It was then rebuilt by someone who knows these trannies and has been fine since. I really think it's a great tranny if it's been cared for properly.
Drifting
Joined: Dec 2003
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From: Westfield MA
From what I can gather, there where changes made in 86 which improved the OD unit. I have read that an 84 or 85 will not make it past 30K miles without some work being done. There are only a few places that know how to work on them, so if this one hasn't been done, it may need it in the near future, if it has already been rebuilt, and you take care of it, it will likely go for a long long time. I liked my 4+3, it takes a little getting used to, but I liked it.
There is a lot of info in the archives and online, keep looking and you will become an expert. Bottom line, many people will shy away from the 4+3, but it isn't a reason to stay away from the car if it is otherwise up to snuff.
There is a lot of info in the archives and online, keep looking and you will become an expert. Bottom line, many people will shy away from the 4+3, but it isn't a reason to stay away from the car if it is otherwise up to snuff.
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Joined: Mar 1999
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From: Oslo, Norway
Hi.
I have an 85 4+3 z-51. The car I love , but had an issue with the overdrive unit. I heard "transmission" noise and suddenly one day it looked like the clutch was bad in reverse. I nearly could not go backwards. showed it was a bearing and it had worn the overdrive wall agains the gearbox. I had to get a new one and got a much later overdrive that did not have the TV wire. These are much stronger and it has worked well since and that is now 45 000 miles. I have had the car now since 1997.
The car handles very nicely with my z-51 option. I have changed to polyurethane bushinings in the suspension and that made a big difference.
If I had this difficulty now I would have changed to a Tremec gearbox. That is plug and play more or less and handles an awful lot of torque and hp.
Good luck.
I have an 85 4+3 z-51. The car I love , but had an issue with the overdrive unit. I heard "transmission" noise and suddenly one day it looked like the clutch was bad in reverse. I nearly could not go backwards. showed it was a bearing and it had worn the overdrive wall agains the gearbox. I had to get a new one and got a much later overdrive that did not have the TV wire. These are much stronger and it has worked well since and that is now 45 000 miles. I have had the car now since 1997.
The car handles very nicely with my z-51 option. I have changed to polyurethane bushinings in the suspension and that made a big difference.
If I had this difficulty now I would have changed to a Tremec gearbox. That is plug and play more or less and handles an awful lot of torque and hp.
Good luck.
Melting Slicks
Joined: Feb 2006
Posts: 2,753
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From: backwoods upstate ny
use the third pedal
the o/d uses auto trans friction discs to engage/disengage, and those auto trans discs are simply not up to that job...disable the computer control over the o/d and shift in/out of 5th gear ( o/d ) using the clutch and the trans will last forever.
ask those "experts" that tell you the 4+3 is bad news if they have ever owned one, expect their answer to be "no, but, but, but"...luv mine
ask those "experts" that tell you the 4+3 is bad news if they have ever owned one, expect their answer to be "no, but, but, but"...luv mine
Intermediate
Joined: Jul 2007
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From: Middle of the United Kingdom
I really enjoyed mine too - nice mechanical feel to it as well. You can always bypass the OD so it's fully manual, which stops that irritating kick-in at low speeds sometimes, or kicking out when you're accelerating around a corner 
Adds another bit of interaction too
Best used when you've got over 40mph on the clock and are settling down to a cruise, rather than dropping in and out......I always clutched whenever I engaged or disengaged mine too - something I picked up on here. Not sure whether that's actually necessary though, none of my Triumphs ever needed that and they're all designed to be flicked into and out of OD at will.
<edit> Just read the above! Seems it is worthwhile then
Harder to miss a shift (expensively) than the 6 speeder, too.....guy I was speaking to today had his friend toast his ZR1 by going from 4th to 2nd at top whack. Nasty!
Adds another bit of interaction too
Best used when you've got over 40mph on the clock and are settling down to a cruise, rather than dropping in and out......I always clutched whenever I engaged or disengaged mine too - something I picked up on here. Not sure whether that's actually necessary though, none of my Triumphs ever needed that and they're all designed to be flicked into and out of OD at will. <edit> Just read the above! Seems it is worthwhile then
Harder to miss a shift (expensively) than the 6 speeder, too.....guy I was speaking to today had his friend toast his ZR1 by going from 4th to 2nd at top whack. Nasty!
Last edited by Lashout_UK; Jun 22, 2008 at 12:24 PM.
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Joined: Jun 2007
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From: Hatfield/Williamsport Pa
Wow guys. Thanks for all the input. Unfortunetaly, I decided not to look at it. I'm in a tight money situation if I do end up purchasing the car, and I don't think I can risk anything going wrong. (Im a 21 year old college student) Especially with some of the stories I've heard. I don't doubt that anything will go wrong, I just can't risk it. Thanks for all the timely input.
Le Mans Master
Joined: Sep 2005
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From: Jenks OK
Wow guys. Thanks for all the input. Unfortunetaly, I decided not to look at it. I'm in a tight money situation if I do end up purchasing the car, and I don't think I can risk anything going wrong. (Im a 21 year old college student) Especially with some of the stories I've heard. I don't doubt that anything will go wrong, I just can't risk it. Thanks for all the timely input.
Instructor
Joined: Oct 2002
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From: Hanover Ontario
I can see money being an issue (I sometimes refer to my car as the money pit) but the transmission isn't really the issue. The 4+3 works great as long as it's maintained. The real issue on these cars is the fact that unless you can do the work yourself you have to pay someone for the labour. My experience has been that everything takes twice as long to do on this car as on something else (anyone ever tried to change the battery). They're great cars that happen to cost alot to operate but the transmission isn't the reason they cost so much.
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I can see money being an issue (I sometimes refer to my car as the money pit) but the transmission isn't really the issue. The 4+3 works great as long as it's maintained. The real issue on these cars is the fact that unless you can do the work yourself you have to pay someone for the labour. My experience has been that everything takes twice as long to do on this car as on something else (anyone ever tried to change the battery). They're great cars that happen to cost alot to operate but the transmission isn't the reason they cost so much.
Last edited by ekess744; Jun 22, 2008 at 07:51 PM.
Safety Car
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From: Pennsylvania
the o/d uses auto trans friction discs to engage/disengage, and those auto trans discs are simply not up to that job...disable the computer control over the o/d and shift in/out of 5th gear ( o/d ) using the clutch and the trans will last forever.
ask those "experts" that tell you the 4+3 is bad news if they have ever owned one, expect their answer to be "no, but, but, but"...luv mine
ask those "experts" that tell you the 4+3 is bad news if they have ever owned one, expect their answer to be "no, but, but, but"...luv mine
These "experts" always go by what someone else told them from someone who knew somebody else. Not a good idea to ask what people think about options in a car that they never had.
Melting Slicks
Joined: Jan 2004
Posts: 2,659
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From: Oxford CT
I drive my 87 4+3 everyday, it has 223k on it. At about 150k the overdrive took a dump and I got it repaired for $650 and it has been fine since. The only thing I can tell you NOT to do is to roll the car and pop the clutch to start it, that will damage the OD. I like my 4+3!
