C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Replacing the Transmission...

Thread Tools
 
Search this Thread
 
Old Aug 10, 2009 | 10:51 AM
  #1  
WoodVette's Avatar
WoodVette
Thread Starter
Intermediate
 
Joined: Aug 2009
Posts: 33
Likes: 0
From: Las Vegas NV
Default Replacing the Transmission...

Ok...everything I read, everyone I talk to says the weakest link in my C4 is the 4+3 tranny. What can I switch it over to? What is the best tranny for my new money pit???
Reply
Old Aug 10, 2009 | 11:25 AM
  #2  
Paul Ruggeri's Avatar
0Paul Ruggeri
Former Vendor
 
Joined: Nov 2006
Posts: 2,482
Likes: 3
From: Carmichael ca
Default

Your best bet is a find someone parting an automatic car and get erverything for the conversion. There are kits to swap in Tremecs, but they aren't cheap.
Reply
Old Aug 10, 2009 | 11:45 AM
  #3  
Demonic85's Avatar
Demonic85
Team Owner
 
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Default

The best affordable replacement is the ZF6 found in '89-'96 manual corvettes. A new one goes for about $1400, unfortunately you'll have to replace everything else as well since the 4+3 hydraulics wont work.

The good thing about the aftermarket transmissions is that some will bolt right up using your existing components and they're a lot stronger.
Reply
Old Aug 10, 2009 | 11:46 AM
  #4  
WoodVette's Avatar
WoodVette
Thread Starter
Intermediate
 
Joined: Aug 2009
Posts: 33
Likes: 0
From: Las Vegas NV
Default

Which aftermarket trannies will bolt right up???
Reply
Old Aug 10, 2009 | 11:53 AM
  #5  
jhammons01's Avatar
jhammons01
Le Mans Master
10 Year Member
 
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Default

if you can deal with a not so perfect shifter (puts flame suit on) you can use a T5....there are plenty of 5spds available for $300-$400....

Anetheses had a nice write up on it.

The Super T10 in your car now is a stout tranny. It can be rebuilt for a few hundred dollars as well. Are you trying to eliminate the O/D and if so where are you going with this??

I mean, what exactly is your issue for wanting to yank the whole system?
Reply
Old Aug 10, 2009 | 11:59 AM
  #6  
WoodVette's Avatar
WoodVette
Thread Starter
Intermediate
 
Joined: Aug 2009
Posts: 33
Likes: 0
From: Las Vegas NV
Default

I just bought the car. It's hard to even find the shift **** and button for the thing. I just don't want to start putting money into this...and have problems with the tranny. I heard the middle plate is what gives out and mixes the gear lube with the auto tranny fluid in the OD.

I just bought her for a hobby car....want her to look good and run good. I love the body...the look of her. But if this tranny is ok..then I am ok with it. I just don't know much about this tranny or how it works?
Reply
Old Aug 10, 2009 | 12:01 PM
  #7  
skybolt31's Avatar
skybolt31
Drifting
20 Year Member
All Eyes On Me
Liked
Loved
 
Joined: Dec 2003
Posts: 1,493
Likes: 94
From: Westfield MA
Default

Originally Posted by jhammons01
I mean, what exactly is your issue for wanting to yank the whole system?
Are you modding your engine and fear that the 4+3 won't handle the power or just looking to replace a part that appears to have a poor reliability record or looking for a nicer shifting or more conventional transmission?

Each of your options, Tremac, ZF-6, Richmond, T-56, T-5 or automatic has advantages and disadvantages. You will find strong believers for each of them here on the list, but need to know what your goals and issues are to give advice as to which one is the "best" for you.
Reply
Old Aug 10, 2009 | 12:05 PM
  #8  
WoodVette's Avatar
WoodVette
Thread Starter
Intermediate
 
Joined: Aug 2009
Posts: 33
Likes: 0
From: Las Vegas NV
Default

I would like to bump the hp to about 300 or so....but the main reason for thinking of the switch is reliability issues...and all the bad talk I have heard about this transmission.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

5 Best & 5 Most Overrated Corvette Track Packages of All Time!

 Joe Kucinski
story-1

Every 2027 Corvette Engine Explained

 Joe Kucinski
story-2

Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

 Verdad Gallardo
story-3

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-4

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-5

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-6

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-7

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-8

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-9

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
Old Aug 10, 2009 | 12:49 PM
  #9  
jhammons01's Avatar
jhammons01
Le Mans Master
10 Year Member
 
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Default

^^Yes, there are some reliability issues with the O/D. And yes that Plate is $275 by itself. And yes the seal for the reverse output goes south and the oil pumps from the T10 to the O/D unit.

But if you do like I did, and pull that thing at the first sign of trouble...you can get a relatively cheap rebuild and go for another spell before you see trouble again.

The issues lie in people driving it into the ground....once it stops working all together, there are real repair issues that do cost money
Reply
Old Aug 10, 2009 | 02:08 PM
  #10  
dclafleur's Avatar
dclafleur
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2005
Posts: 6,551
Likes: 36
From: Jenks OK
Default

The 4+3 is a decent transmission, if yours is working fine just keep maintaining it and it should be fine. I intend to replace mine with a TKO 600 at some point but if yours is working no reason to swap it out right away.
Reply
Old Aug 10, 2009 | 02:36 PM
  #11  
jhammons01's Avatar
jhammons01
Le Mans Master
10 Year Member
 
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Default

^^you are right.

Borg Warner T10 bullet proof
Borg Warner Super T10 is junk

How does that happen when the difference is the rear housing, short rear output shaft and the addition of a reverse output?? The main internals are identical.

The over drive is a two speed auto....

Manny people autocross and race the thing without trouble. Knowledge is power.
Reply
Old Aug 10, 2009 | 04:43 PM
  #12  
powerpigz-51's Avatar
powerpigz-51
Drifting
10 Year Member
 
Joined: May 2006
Posts: 1,428
Likes: 7
From: Chewelah Wa
Default

4+3 replacement or even a rebuild is way cheaper and easier than retrofitting something else (auto, 6 speed, t5, etc.). A lot of the problems associated with the 4+3 were engineered out of the later year units. Not only that...they are fun and unique. Shift handles and buttons are available aftermarket, just a rethread is required. These units were coupled to the Calloway corvettes, so 300 HP is within its capabilities.
Reply
Old Aug 10, 2009 | 05:11 PM
  #13  
James93LT1's Avatar
James93LT1
Drifting
Veteran: Air Force
Veteran: National Guard
20 Year Member
 
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Default

Originally Posted by dclafleur
The 4+3 is a decent transmission, if yours is working fine just keep maintaining it and it should be fine. I intend to replace mine with a TKO 600 at some point but if yours is working no reason to swap it out right away.
If your trans is working, maintain it, and if or when it breaks, replaced it.
Reply

Get notified of new replies

To Replacing the Transmission...





All times are GMT -4. The time now is 02:37 PM.

story-0
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-1
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-2
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-3
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-4
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-5
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-6
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-7
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-8
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-9
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE