No kickdown on Pontiac Th400

Asked by TCFirebird68 Feb 15, 2019 at 12:05 AM about the 1968 Pontiac Firebird Coupe

Question type: General

I have a 1968 firebird convertible. It has a
400 motor. I recently acquired TH400
transmission out of a 1969 Catalina. I
installed it in my car and am getting ready to
fire it up. But I noticed it does not have a
kick down. Is that right or is it missing?
Does it even have one in that year? How is it
suppose to kick down.

2 Answers

101,635

TH400s have an electrical kickdown, not a mechanical linkage. Google "TH400 kickdown switch" for part sources. On models that came with the TH400 back then, there was an electrical switch that was mounted at carb on throttle linkage, when the linkage was at WOT (wide open throttle), it connected and supplied 12V to a solenoid in the tranny that did two things, increased line pressure to prevent damage to clutch and downshift tranny (depending on gear). Lots of TH400 retrofits involve installing that switch as well. Don't run tranny without it, as again you can damage clutch due to lack of increased line pressure.

1 people found this helpful.

Your Answer:

CarGurus Experts

  • #1
    Samuel Moore
    Reputation
    1,590
  • #2
    taver91
    Reputation
    1,320
  • #3
    Paul Martin
    Reputation
    1,270
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet Camaro
15 Great Deals out of 467 listings starting at $11,999
Used Chevrolet Corvette
19 Great Deals out of 777 listings starting at $18,999
Used Ford Mustang
30 Great Deals out of 1,599 listings starting at $7,999
Used Pontiac GTO
4 listings
Used Dodge Charger
45 Great Deals out of 858 listings starting at $5,995
Used Ford Mustang Shelby GT500
39 listings starting at $34,895
Used Porsche 911
16 Great Deals out of 243 listings starting at $22,980

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.