69 GTO - 4speed. 'Slips' in 4th at 100mph?
I've only had this car for about a month, and only the past week has it done this on me...
Driving hard and fast, dropped it in third... fast as hell acceleration... drop it to fourth, nice long chirp of tires, fast as hell acceleration... then all the sudden, it stops moving forward... The RPMS stop climbing, and it just sits there at that speed, almost as if I've got a speed limiter.
The first two weeks I got the car, it went to 120mph fine... great, no problems... Quick as hell too.
Usually it's happened to me right at 100-110mph, but yesterday it happened to me at 80mph. When this occurs, I dont hear any odd noises, the shifter is still in fourth... I've still got traction... What gives? It's a hard running 400 motor, and only does this in fourth gear. Any clues what is going on? I'm very amateur at transmissions and such - I know how to use them - could it be transmission related since it only happens in 4th? Suggestions?
Thanks in advance!
Driving hard and fast, dropped it in third... fast as hell acceleration... drop it to fourth, nice long chirp of tires, fast as hell acceleration... then all the sudden, it stops moving forward... The RPMS stop climbing, and it just sits there at that speed, almost as if I've got a speed limiter.
The first two weeks I got the car, it went to 120mph fine... great, no problems... Quick as hell too.
Usually it's happened to me right at 100-110mph, but yesterday it happened to me at 80mph. When this occurs, I dont hear any odd noises, the shifter is still in fourth... I've still got traction... What gives? It's a hard running 400 motor, and only does this in fourth gear. Any clues what is going on? I'm very amateur at transmissions and such - I know how to use them - could it be transmission related since it only happens in 4th? Suggestions?
Thanks in advance!
I'm assuming it's a manual since they didn't have 4 speed autos back then.
It could be a mechanical govenor issue. What kind of transmission is it, who made it, etc? I'm not to familiar with the old school manuals, just throwing what I know at it.
It could be a mechanical govenor issue. What kind of transmission is it, who made it, etc? I'm not to familiar with the old school manuals, just throwing what I know at it.
DO you have a turbo 350 with overdrive, or a 700r4?
the first thing i would check is your vacuum modulator, it controls you shift points. Also do when you are driving at 100 -120 do you have it to the floor? IE is are you in your passing Gear?
If it is not a auto than just throw that out the door.
the first thing i would check is your vacuum modulator, it controls you shift points. Also do when you are driving at 100 -120 do you have it to the floor? IE is are you in your passing Gear?
If it is not a auto than just throw that out the door.
Oh yeah, and just FYI, the only times I'll be going that fast in this car is on a very very clean and straight road, where I can see -very- far ahead of me...
Its nowhere as near as relable as my 02 SS... had that thing up to 150... all I can say is damn. Anyhow, back to my transmission issue?
Know any shops that'll look?
Its nowhere as near as relable as my 02 SS... had that thing up to 150... all I can say is damn. Anyhow, back to my transmission issue?
Know any shops that'll look?






