727 question

[1968 signet]

i was wondering what the different is between the 1962- 1970 727 and a 71 and up. i order a rebuilt kit and thought i had a 1966 727 but to find out its a 1972 727.

 

[3404spdvaliant]

Part throttle kick down 71' up.
Early torque flight had a rear pump that allowed push starting,
65'-earlier I think.

I'd rather have the 72'.

 

[SGBARRACUDA]

There is a piston seal that is wider in one than the other, so the seal kits are different.

 

[1968 signet]

that it , is one stronger than the other?

 

[bOb shingler]

the pre 72's have a better kick down piston.

 

[fishy68]

All the above is correct. 66-71 is considered the best to get because it has the old style kickdown servo but it's possible to put the old style servo in the newer trans. The 71 has part throttle kickdown 66-70's don't have like 3404spdvaliant said. That's one of those options some guys like and others don't. Some 727's are heavier duty than others (some have 3 and others have 4 clutch plates in the front carrier and some have a 3 pinion and others 4 pinion planetary gear sets) and the year don't make a diff. there. It depends on what the application was. Post the casting # located on the drivers side pan rail above the pan and I'll look it up and see what it was uses behind.

In essence with all the required HD parts you can make any 727 as good as the next.

 

[1968 signet]

pk3515845 3643

 

[fishy68]

That trans was used in the following:

1971 E, B, and C bodies with a 383 2 barrel engine.

It also shows being used behind a 1972 Dodge body but don't specifiy which body. Had a 400 engine 2 barrel.

Either way since it's a big block trans it'll have the good 4 disc front clutch pack and 4 pinion planetaries. The only thing you need to do is upgrade the kickdown lever to a 3.8 or 4.2 ratio and add more springs to the front clutch pack. 12 will do you fine. It probably only has 6 or 8 since it was a cruiser trans.

 

[1968 signet]

the drum has 9 springs can i get more springs out of another drum and it only has 3 discs.

 

[fishy68]

the drum has 9 springs can i get more springs out of another drum and it only has 3 discs.

Yes you can add springs from a different carrier as long as their the same length. There was 2 diffetent lengths used depending on the year but I don't remember what year they changed length. Justmatch them up and you'll be fine. And that's odd that it only has 3 clutch plates. All big block trans I've seen had 4 discs. Maybe somebody had it apart before and swapped in the 3 disc carrier. You can try to locate a 4 disc carrier made from 70 up to replace it with. You really need it when using it behind a big block to handle the torque.

 

[1968 signet]

i found a 4 clutch setup, now it only has 10 springs and only 10 spring will fit. the other 3 clutch setup can hold up to 15 springs and the springs are shorter, than the 10 spring setup so sould i use 10 springs or change the part that holds the spring and put the 12 shorter springs or sould i get so more longer springs, also the 15 spring setup is .020 thinner than the 10 spring setup. sorry i dont know the name of the parts, if you need pics let me know thanks for all your help

 

[1968 signet]

and also i ordered the 4.2 lever and they sent me a 5.0 lever will this work or sould i send it back and get a 4.2.

 

[fishy68]

The part the springs set in is called the piston. I've heard of the piston that only holds 10 springs and is thinner but I'm sorry I don't know if you can swap in your other piston or not cause I haven't ever seen one to compare it to the other style. What I think I'd do if I were you is use the clutch carrier setup that uses the 10 springs and 4 discs and send back the 5.0 lever and put a 3.8 lever in it and block the accumulator. That should shift real firm and not overlap any. The accumulator is a hydraulic cushion for the kickdown band. By blocking it the band will apply quicker and make up for the slower ratio lever which you need when only running 10 springs.

 

[1968 signet]

got the trans done thanks for all your help.

 

[fishy68]

got the trans done thanks for all your help.

Good deal Sig:cheers: