Need help with a 4x3 tranny
Thread Starter
Race Director
Joined: Nov 2001
Posts: 11,530
Likes: 0
From: New Bloomfield Pa
Cruise-In VI Veteran
St. Jude Donor '03-'04-'05-'06-'07-'10
Need help with a 4x3 tranny
A buddy of mine just picked up an 85 and called me when it got to his place.
He said it is a 4 speed. I said it was a 4x3 but I have never driven one. so my question is
1. Why is it called 4x3 ( I am assuming 3 gear shave O/D)?
2. How do you switch to O/D
3. He said it wont go in reverse...any ideas?
He said it is a 4 speed. I said it was a 4x3 but I have never driven one. so my question is
1. Why is it called 4x3 ( I am assuming 3 gear shave O/D)?
2. How do you switch to O/D
3. He said it wont go in reverse...any ideas?
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
4+3
If it is a 4 plus 3, you have overdrive in 2nd, 3rd, and 4th.
I think you push the center of the shifter **** to actuate the overdrive.
some early ones had a overdrive button on the center console I think
I think you push the center of the shifter **** to actuate the overdrive.
some early ones had a overdrive button on the center console I think
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
so much to say...first...do a search on here...look for "4+3", "Doug Nash" or "OD unit" ....those will bring up a ton of threads...
basically is an OD unit mated to a 4 speed manual box...there are 7 forward gear ratios...in order, they are: 1, 2, 2OD, 3, 3OD, 4, 4OD...although i only use the OD in 4th gear over 55mph...
when you say that it won't go into reverse...what exactly do you mean...will the shifter not move into the "reverse" gate or do you mean that you can get the shifter into reverse, but the car won't move?
those are 2 very different problems....
how many miles are on the car...any service records on the transmission?
depending on when his car was manufactured, the OD unit switch is either on the console, rearward on the shifter (next to the power mirror L/R switch) or the actual shift button (like on an automatic) on the top of the shifter is the button...
as a tip...always use the clutch when shifting...even the OD unit...its prolong the eventual failure.
there are plenty here who know plenty about the 4+3...so ask away!
basically is an OD unit mated to a 4 speed manual box...there are 7 forward gear ratios...in order, they are: 1, 2, 2OD, 3, 3OD, 4, 4OD...although i only use the OD in 4th gear over 55mph...
when you say that it won't go into reverse...what exactly do you mean...will the shifter not move into the "reverse" gate or do you mean that you can get the shifter into reverse, but the car won't move?
those are 2 very different problems....
how many miles are on the car...any service records on the transmission?
depending on when his car was manufactured, the OD unit switch is either on the console, rearward on the shifter (next to the power mirror L/R switch) or the actual shift button (like on an automatic) on the top of the shifter is the button...
as a tip...always use the clutch when shifting...even the OD unit...its prolong the eventual failure.
there are plenty here who know plenty about the 4+3...so ask away!
Instructor
Joined: Oct 2006
Posts: 141
Likes: 7
From: Deltona Florida
http://www.gearzone.net/43table.htm
this is a great link to find out the characteristics of your year 4+3
this is a great link to find out the characteristics of your year 4+3
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
if the car will shift into reverse and all you hear is grinding and no movement, just pony up for another OD unit...but if you simply can't get it into reverse, it could be a bad linkage adjustment or messed up shift lockout...
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Hmm "4x3", "buddy just bought the car"...
Is there any chance he just isn't pulling up on the shifter to enable engaging reverse?
Oh yeah, and as for 4x3. It came standard on the "Off-Road" package for these guys... Now why would they install that on a Corvette?
Is there any chance he just isn't pulling up on the shifter to enable engaging reverse?
Oh yeah, and as for 4x3. It came standard on the "Off-Road" package for these guys... Now why would they install that on a Corvette?
Thread Starter
Race Director
Joined: Nov 2001
Posts: 11,530
Likes: 0
From: New Bloomfield Pa
Cruise-In VI Veteran
St. Jude Donor '03-'04-'05-'06-'07-'10
well I went over after work and showed him what he needs to do. It will go in reverse and move...just does not sound good.
I told hi yank it out and replace with a 5 speed
I told hi yank it out and replace with a 5 speed
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Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
if it grinds once reverse is engaged....yup...OD is shot...bet if you take off the OD fluid pan it'll be filled with clutch material...
as far as a swap...there are other guys around here who know whats easily fits in and what needs to be done...i seem to rmeember there being some concern regarding the 5 speeds...location of shifter or something...the ZF6's go in too with a little modification...but thats not my area...
as far as a swap...there are other guys around here who know whats easily fits in and what needs to be done...i seem to rmeember there being some concern regarding the 5 speeds...location of shifter or something...the ZF6's go in too with a little modification...but thats not my area...
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
A buddy of mine just picked up an 85 and called me when it got to his place.
He said it is a 4 speed. I said it was a 4x3 but I have never driven one. so my question is
1. Why is it called 4x3 ( I am assuming 3 gear shave O/D)?
2. How do you switch to O/D
3. He said it wont go in reverse...any ideas?
He said it is a 4 speed. I said it was a 4x3 but I have never driven one. so my question is
1. Why is it called 4x3 ( I am assuming 3 gear shave O/D)?
2. How do you switch to O/D
3. He said it wont go in reverse...any ideas?
