1966 electra trans swap

Aren't all of the Nailhead '64 to '66 3 speed 400 auto transmissions, switch pitch's except for possibly the '64?

 

I stand corrected. I do have a switch pitch. I got the best picture I could of the tag. It's included here. I also made a video of me running up the car to 60 so we can figure out what rpms it's at. Heres the link to that : I tried finding out my axle ratio by putting it in neutral and spinning the rear wheels. My axle isn't a posi so it didn't really work. I put the car into drive (with the engine off) and spun the wheels. It was 2:1. I also included a picture of the body tag. Maybe y o u can help me decode it.

 

A switch pitch might be converted to the later pan/filter (I always do) and
some very late (67) were built that way. But any switch pitch must have the
2 electrical lugs on the side, each responding to 12V battery with a click
inside. A few years later some fixed transmissions were built with 2 lugs,
but one was connected to an emissions control switch. Bruce Roe

 

I got the strut rod bushings replaced. Boy that was a job. I took the car for a drive and it still pulls to the right, so it's due for an allignment tomorrow morning. The next thing I'll tackle is all the leaks. It's leaking every fluid under the hood. I'm not kidding.

 

Buick did a really stupid thing (imo) and stamped the gear ratio on the bottom of the diff housing. Right where it will always get scraped! Also, if you change the centre section the stamped ratio is no longer valid if you changed the ratio which is my case, My car came with a 3:07 posi. I changed it to a 3:23. I wrote it on the top of the housing in paint pen.

 

I have yet to figure out what my ratio is. My axle is so dirty I can't see any numbers. Where exactly do I need to look for the numbers?

 

I think it's the same diff as mine and will be stamped on the very bottom of the "pumpkin"

 

It is so simple to jack up a wheel and see how many driveshaft turns make the raised
wheel go around exactly twice. For a posi raise both wheels, mark the start positions,
and see how many drive shaft turns get both wheels around once. Check that they
both did exactly one, adjust their positions if needed. Bruce Roe

 

I've determined that my trans isn't shifting into 3rd. It shifts first at about 10 mph and then again at about 20. From then on its one speed. Any clue as to why it's not shifting into 3rd? Maybe a mad modulator? Not enough vacuum?

 

If it shifts twice, that's three gears. Unless I am misreading your post. You should be able to adjust the modulator valve by removing the vacuum line and inserting a small flathead screwdriver to turn the screw clockwise. Start with a couple turns then a road test. I wouldn't seat the screw completely. Readjust if necessary and road test again.

 

You have a point. I'll leave it alone for now.

 

You should try adjusting the modulator valve. It's quite simple and would allow you to set the shift points to your liking.

 

Normal shift points for the early ST400 are approx. 7-10MPH from 1st.-2nd. & 14-20MPH 2nd.-3rd. NO MOD valve adjustment needed. Only adjustable if you have the SMALL modulator. The LARGE stock modulator is NOT easily adjustable.

 

That means it is shifting into third. It shifts at about 10 then again at about 15

 

I have a Buick switch pitch, think its a 67. I found even floored, it would shift
at very low speeds. I got a spare governor and did the usual springs-weights
tuning to shift where I wanted. The after market modulator I regard as more
for presetting hashness. Bruce Roe

 

Funny story. I traded my electra for a newer vehicle. I was tired of the constant money spending. Anyways the guy I traded with told me by the time he got home the motor was ticking. Oil was dripping all over the floor. And when he cranks the engine up there's a rattle noise. I think the oil pump went out.....but not my problem. I hate that it had to happen with him....i guess the Lord was looking out for me. He gave me a reliable vehicle because he knew the buick was about to need expensive work.

 

Jonah, i'm beginning to think your Electra wasn't the low 44,000 mile car you thought and it could of rolled the odometer, or you abused the heck out of it? Oil leaks out for a reason and could of starved the pump..
Even if low miles and sitting so long seals do dry out..Not something you don't already know..