700r4 "un" modify questions

[parisherj]

Hey guys, OK so i have a 86 k10 mild 350 with 700r4. Stock tires nothing fancy.

The trans went out a few weeks ago so a friend gave me one he said was a good one. I installed it only to find when it went from 1 to 2 it would almost break your neck. It slams like you hit something. Scared its going to break something, t-case, rear, etc.  Pulled it back out and got to looking into it and found these issues.

1-2 accumulator and 3-4 accumulator no springs just sleeves over the pin holding the piston to the separator plate. Also looks to be 3 check balls are missing on the case side.

The check balls are an easy one to fix. My question is the accumulator springs. Different colors mean different shift firmness right?
Which color spring should i put back into this thing. I use this truck mostly for hauling wood, My boat and my car trailer. So i want it firm but not breaking your neck firm.

Any ideas would be great. Thanks Guys.

[BADAZ chevy guy]

Sounds like a shift modification. Watch the video below and see if this looks like what you've found inside.

https://www.youtube.com/watch?v=2B8nyfrFKyo

If it's been modified, replacing the check balls may mess it up worse. 

[parisherj]

Thanks for the info. I watched the video and some of the stuff doesnt match up to what i have. According to the guy i got it from he put a shift kit in it a few years ago but can't remember what kind. He thinks B&M but not sure. All he remembers doing is replacing the sep plate, replacing the acc springs with sleeves and leaving out a few check balls. And of course he doesn't have the oem springs he took out. I bought a corrector kit (sk700jr) that includes springs for the 1-2 acc but it says to reuse the stock 3-4 spring. Witch i don't have.

[BADAZ chevy guy]

There's 3 videos in the series this guy did. Some of the mods include blocking a servo, and a valve, with check balls that are driven in and can't be removed. Also, if your separator plate has been drilled out, you may need to get another one. Depending on what your guy did you may not be able to "UN-Modify" the transmission.

[parisherj]

Thanks. From the sounds of it I might have been better off rebuilding the one I had.