WOT 4th shift
Thread Starter
Banned
Joined: Nov 2008
Posts: 2,435
Likes: 1
From: Central Florida
Car: 89 Camaro RS running MS2X
Engine: .48/.60AR T3/T4 2.8L V6
Transmission: Rebuilt 700R4 2500 stall
Axle/Gears: Next to break...
WOT 4th shift
awhile back i had asked about a mod to make WOT 3rd to 4th shift, someone told me about the allen plug mod, but never provided details.
i dont need to know if or how it works, i need to find someone who knows the link to this mod, cause i have been searching for hours to no avail.
thanks for the help in advance
i dont need to know if or how it works, i need to find someone who knows the link to this mod, cause i have been searching for hours to no avail.
thanks for the help in advance
Member

Joined: Dec 2007
Posts: 475
Likes: 3
From: Minnesota
Car: '88 Iroc
Engine: Single turbo Vortec 5.7, Megasquirt
Transmission: Probuilt 700r4 3000 stall Vigilante
Axle/Gears: Moser 9" 3.25 w/True Trac
Re: WOT 4th shift
Have you checked on probuilt automatics forum? If you can't find it there you could ask Dana directly either on the phone or through the forum. I might have it saved somewhere. If I can find it I'll post
Senior Member
iTrader: (1)
Joined: Mar 2005
Posts: 646
Likes: 0
From: San Antonio
Car: 1981 Camaro; 1986 Z28
Engine: LT1; LT1
Transmission: 6 speed; 6 speed
Axle/Gears: 3.73; 3.42
Re: WOT 4th shift
The only thing I know of is a kit for a modified valve that allows the trans to shift at WOT. These were used for the Highway Patrol cars that did high speed pursuits. Almost all of the performance trans companies sell it. I haven't heard of any other "tricks" that can be used.
Supreme Member




Joined: Jul 2006
Posts: 2,861
Likes: 785
From: 212 is up in this Bit@#
Car: Resto-Mod 1987 IROC-Z Clone
Engine: Alky fed L92 Vortec Twin-Turbo 6.8L
Transmission: My own built/ design 4L80M
Axle/Gears: Custom 12 bolt (4.10:1)
Re: WOT 4th shift
The most common modification I see is to install a new throttle valve plunger sleeve such as the one GM used to produce for police (B4C) package vehicles, now made by Sonnax and Superior-Fairbanks. Many companies (Transmissions builders/ Parts departments) offer this sleeve, even B&M and TCI carry it.
How ever it is not recommended for use (by it self) behind engines making over 250HP.
If used behind engines making more power, typically the result in some time will be no fourth gear.
What usually happens... the fourth gear servo piston seal fails and the the 2-4 band will not be applied to hold the Reverse Input Drum.
What should be done: upgrade to a larger oil pump boost valve set and drill the separator plate as per Superior-Fairbanks. Upgrade the 2-4 band and upgrade the fourth gear servo piston. Alto makes some great 2-4 bands and Superior-Fairbanks makes a great fourth gear servo piston.
With these modifications a wot 3-4 shift should be maintained safely unless the transmission has any other problems or vehicle has too much motor for a stock 700R4.
How ever it is not recommended for use (by it self) behind engines making over 250HP.
If used behind engines making more power, typically the result in some time will be no fourth gear.
What usually happens... the fourth gear servo piston seal fails and the the 2-4 band will not be applied to hold the Reverse Input Drum.
What should be done: upgrade to a larger oil pump boost valve set and drill the separator plate as per Superior-Fairbanks. Upgrade the 2-4 band and upgrade the fourth gear servo piston. Alto makes some great 2-4 bands and Superior-Fairbanks makes a great fourth gear servo piston.
With these modifications a wot 3-4 shift should be maintained safely unless the transmission has any other problems or vehicle has too much motor for a stock 700R4.
Thread Starter
Banned
Joined: Nov 2008
Posts: 2,435
Likes: 1
From: Central Florida
Car: 89 Camaro RS running MS2X
Engine: .48/.60AR T3/T4 2.8L V6
Transmission: Rebuilt 700R4 2500 stall
Axle/Gears: Next to break...
Re: WOT 4th shift
The most common modification I see is to install a new throttle valve plunger sleeve such as the one GM used to produce for police (B4C) package vehicles, now made by Sonnax and Superior-Fairbanks. Many companies (Transmissions builders/ Parts departments) offer this sleeve, even B&M and TCI carry it.
How ever it is not recommended for use (by it self) behind engines making over 250HP.
If used behind engines making more power, typically the result in some time will be no fourth gear.
What usually happens... the fourth gear servo piston seal fails and the the 2-4 band will not be applied to hold the Reverse Input Drum.
What should be done: upgrade to a larger oil pump boost valve set and drill the separator plate as per Superior-Fairbanks. Upgrade the 2-4 band and upgrade the fourth gear servo piston. Alto makes some great 2-4 bands and Superior-Fairbanks makes a great fourth gear servo piston.
With these modifications a wot 3-4 shift should be maintained safely unless the transmission has any other problems or vehicle has too much motor for a stock 700R4.
How ever it is not recommended for use (by it self) behind engines making over 250HP.
If used behind engines making more power, typically the result in some time will be no fourth gear.
What usually happens... the fourth gear servo piston seal fails and the the 2-4 band will not be applied to hold the Reverse Input Drum.
What should be done: upgrade to a larger oil pump boost valve set and drill the separator plate as per Superior-Fairbanks. Upgrade the 2-4 band and upgrade the fourth gear servo piston. Alto makes some great 2-4 bands and Superior-Fairbanks makes a great fourth gear servo piston.
With these modifications a wot 3-4 shift should be maintained safely unless the transmission has any other problems or vehicle has too much motor for a stock 700R4.
well i dont think ill have a problem with it then, id be lucky if i was pulling 160hp. also getting ready to install a transmission oil cooler.
the mod involved 2 allen head screws put into the valve body and grinded down. something to that effect. the description i got on my thread awhile back was pretty vague. just wanted to see if anyone knew where the instructions were.
Thread
Thread Starter
Forum
Replies
Last Post
AmpleUnicorn88
Interior Parts Wanted
16
Nov 29, 2015 05:45 PM






