one to four
Thread Starter
Pro
Joined: Feb 2006
Posts: 671
Likes: 10
2021 C4 of the Year - Unmodified Finalist
one to four
I have a 93 with ZF 6. I've had a few people ask me about the one to four shift "lock out".
They claim it FORCES a shift from first to fourth. Sounds like horse hockey to me. I've had the light come on many times and never had any problem shifting it in the usual 1,2,3,4 manner.
What's the deal with this forced shifting from 1 to 4 locking out second?. Is it BS or what?
They claim it FORCES a shift from first to fourth. Sounds like horse hockey to me. I've had the light come on many times and never had any problem shifting it in the usual 1,2,3,4 manner.
What's the deal with this forced shifting from 1 to 4 locking out second?. Is it BS or what?
Pro
Joined: Feb 2006
Posts: 501
Likes: 0
From: Vancouver WA
i dont believe it is BS. it worked on my 97 z28 it wouldnt allow me to shift to 2nd.. on my vette it has the same thing it has just been disabled, but the light still comes on
i know ZF6 and T56 but i would think it is kinda the same concept on both trannys
i know ZF6 and T56 but i would think it is kinda the same concept on both trannys
Intermediate
Joined: Jun 2008
Posts: 49
Likes: 0
From: Schwarzenau / Austria
In most of the ZF6 cars the relay which operates the solenoid at the gear box is already pulled or the connector of the solenoid itself is pulled.
The relay of the 1/4 up you can find on the drivers side behind the battery near the door.
The solenoid and it´s connector is also on the left side of the gear box somewhere in the area where the driver seat is placed (in your case i think it can be a black or blue tag ZF).
The relay of the 1/4 up you can find on the drivers side behind the battery near the door.
The solenoid and it´s connector is also on the left side of the gear box somewhere in the area where the driver seat is placed (in your case i think it can be a black or blue tag ZF).
Race Director
Joined: Oct 2005
Posts: 11,770
Likes: 175
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
I have a 93 with ZF 6. I've had a few people ask me about the one to four shift "lock out".
They claim it FORCES a shift from first to fourth. Sounds like horse hockey to me. I've had the light come on many times and never had any problem shifting it in the usual 1,2,3,4 manner.
What's the deal with this forced shifting from 1 to 4 locking out second?. Is it BS or what?
They claim it FORCES a shift from first to fourth. Sounds like horse hockey to me. I've had the light come on many times and never had any problem shifting it in the usual 1,2,3,4 manner.
What's the deal with this forced shifting from 1 to 4 locking out second?. Is it BS or what?
It left the factory with that feature enabled. CAGS (Computer Aided Gear Selection).
GM used that feature to improve the fuel mileage and avoid the "gas guzzler tax". If fact, that feature is still in use on new Corvettes today.
But, most people will disable it. There are several ways, so more than likely a previous owner has already done this on your car. The "One to Four" light will still come on though. It just won't "force" you to shift to 4th.
