Kick down thingy on the dash on 84

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Preston

Full Access Member
Joined
Jan 25, 2019
Posts
787
Reaction score
355
Location
Mechanicsville VA
First Name
Preston
Truck Year
1983
Truck Model
k10
Engine Size
350
Im a little slow learning about the transmission technology on the old trucks, but I need to set up a kick down for my 85 and using a mid 60’s transmission I was wondering if the set up on my 84 will work and what would I need to get ( what to buy ) it has a vacuum hose coming from the carb and a wire from the 400 transmission other than the one on the linkage I see at the speed shops, and some are using a toggle on the dash. Just thought I would pick your brains on this. Thanks for all your help in advance, let’s see if you can teach an old dog some new stuff.

Correction on the title the thingy is on the firewall (to early have not had my first cup of coffee yet
 

Crispy

Full Access Member
Joined
Apr 5, 2017
Posts
1,454
Reaction score
1,391
Location
Carbon County, Pennsyltucky
First Name
Chris
Truck Year
1989
Truck Model
Suburban V1500
Engine Size
5.7
Not tooooo versed in this but when swapping in a TH400 theres a B&M kit that mounts up to the carb linkage and sends the voltage signal to the trans when needed. This sounds like a an easy way to me. I've never done it but have heard guys use it with great success. I'm sure someone with more knowledge will chime in, hopefully by the time you finish your coffee.
 

Matt69olds

Full Access Member
Joined
Jan 8, 2018
Posts
2,451
Reaction score
3,819
Location
Central Indiana
First Name
Matt
Truck Year
81
Truck Model
GMC 1/2 ton
Engine Size
455 Olds
I bet the mounting bracket for the lockdown solenoid is already under the dash. Get a lockdown switch, run a wire from a fused 12 voltage ignition on power to one terminal other the switch, the other terminal to the kickdown connector on the trans. Make sure the kickdown connector has power when you floor the gas pedal. Not much to it. The switch, wire, and terminals will cost less than 20 bucks
 

Preston

Full Access Member
Joined
Jan 25, 2019
Posts
787
Reaction score
355
Location
Mechanicsville VA
First Name
Preston
Truck Year
1983
Truck Model
k10
Engine Size
350
Thanks Matt I haven’t spent too much time under the dash will take a look it’s not easy for those of us with bifocals though
 

Frankenchevy

Proverbs 16:18
Joined
Jan 3, 2018
Posts
6,084
Reaction score
7,759
Location
USA
First Name
Jeremy
Truck Year
Square
Truck Model
CUCV
Engine Size
Small
The gas pedal switches are actually up around $45 iirc
 

Craig 85

Full Access Member
Joined
Jan 25, 2017
Posts
3,917
Reaction score
4,116
Location
Nashville, TN
First Name
Craig
Truck Year
1985
Truck Model
K30 SRW
Engine Size
454/TH-400/NP205
The first picture is the TH-400 kick down located near the gas pedal. Your truck should have this. The second is the cruise control vacuum break switch near the gas pedal. Mine has a vacuum line that goes from this to the cruise control module behind the carb.

Photo 3. B&M used micro switches in my Star Shifter to prevent starting in Park and neutral, but you could use it for a kick down. They make nitrous kit switches to do the same thing.

You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
 

Preston

Full Access Member
Joined
Jan 25, 2019
Posts
787
Reaction score
355
Location
Mechanicsville VA
First Name
Preston
Truck Year
1983
Truck Model
k10
Engine Size
350
Thanks Craig, but on my 83 k10 there is a switch looking from the front of my truck left of center on the fire wall that has wires on one end and a vacuum hose on the other, I was told that was a kick down switch, I’ll try and get a picture in a while to confirm what I’m referring to, thanks for the help
 
Last edited:

Preston

Full Access Member
Joined
Jan 25, 2019
Posts
787
Reaction score
355
Location
Mechanicsville VA
First Name
Preston
Truck Year
1983
Truck Model
k10
Engine Size
350
You must be registered for see images attach

The switch is shown here the vacuum hose is missing or is that work with the hvac
 
Last edited:

Craig 85

Full Access Member
Joined
Jan 25, 2017
Posts
3,917
Reaction score
4,116
Location
Nashville, TN
First Name
Craig
Truck Year
1985
Truck Model
K30 SRW
Engine Size
454/TH-400/NP205
I think you're referring to the Transmission Controlled Spark Switch. Here's the description per Classic Parts of America.

"This switch mounts on firewall and is a vacuum and electrical switch. It controls the lock up on the converter. Used on trucks with 700R4 automatic transmission."

All of my 7 of my 8 Square Bodys have been 454's with TH-400's. The one that wasn't was a '79 with a TH-350.

https://www.classicparts.com/1982-86-Transmission-Torque-Converter-Lock-Up-
Switch/productinfo/53-604/?gclid=CKqo2vuz2OICFaAgrQYdz8AHzw



You must be registered for see images attach
 

Preston

Full Access Member
Joined
Jan 25, 2019
Posts
787
Reaction score
355
Location
Mechanicsville VA
First Name
Preston
Truck Year
1983
Truck Model
k10
Engine Size
350
I must have a 700r in both of my K10’s thanks for clearing things up for me, I put this th400 out of a mid 60’s GTO in my 85 Silverado, it shifts great just working on the kick down part, guess I’ll have to work things out with the carburetor linkage.
 

Lowered87

Full Access Member
Joined
Dec 12, 2017
Posts
103
Reaction score
99
Location
Oxbow, Saskatchewan
First Name
Adam
Truck Year
1987
Truck Model
R10
Engine Size
350
Lokar also makes a kick down switch for the th400. It has the electrical switch on the transmission.
 

Latest posts

Forum statistics

Threads
44,168
Posts
950,783
Members
36,283
Latest member
Cantrell299
Top