Tranny shifting with jmods, springs, accumulators..which does what?

Lux

Lux

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I've read alot about doing the Jmod as i just picked up the car and thats the next thing i'm going to do.

I have a 97 (also another thing is no one knows for sure what it all has in, some say it might be updated some say its not)

What do you guys recommend? I'm replacing all the fluid with motorcraft Merc 5, doing a Jmod, adding a bigger cooler and temp guage, and tapping the pan for a drain plug and i dont feel like messing with the tranny again for a long time. I want FIRM QUICK shifts but i dont want to break things, i want to be able to beat on it when i want, break the tires loose, but not destroy anything.

There is some reference to leaving certain springs out not doing the 2-3 and etc, everyone has thier own opinion, so my question goes to those who have done the swap, what do you think?

Is there a list somewhere that states "soft, medium, hard, so hard your breaking things shift list what to use and what not to use" and i'm missing it? lol

Thanks for the help
 
Once you drop the pan you will know if some one has opened it up. There will be a plastic plug laying in the bottom if no one has touched it, this is from final assebly where they push the dip stick in and push the plug into the pan.

As far as which level to take J mod I would say go to the 450 HP, as hard is only if you mash it to the floor and hold it there, driving normal it will feel fine. Less slip equals better life. Also adding an external trans cooler is a good idea as well.
 
When I did mine, I left the bottom 1-2 spring, and the 2-3 spring out, and left the original top 1-2 spring in place. At part throttle, it shifts nice and quick, but not neck-snapping. A WOT run will get the car sideways at 60mph, and that's with the stock 3.27 open diff. I also did mine to the highest setting, and after doing it that way, I'll never do the mild setting again. Also mine has been done for about 8K miles of daily driving now, with no problems breaking anything.
 
Blenderhead said:
When I did mine, I left the bottom 1-2 spring, and the 2-3 spring out, and left the original top 1-2 spring in place. At part throttle, it shifts nice and quick, but not neck-snapping. A WOT run will get the car sideways at 60mph, and that's with the stock 3.27 open diff. I also did mine to the highest setting, and after doing it that way, I'll never do the mild setting again. Also mine has been done for about 8K miles of daily driving now, with no problems breaking anything.
Click to expand...

Thats what i wanna know, because on the articles on tccoa it says for the highest setting 300 or whatever, to leave the springs out?

How hard is the BANG at WOT?
 
Blenderhead said:
When I did mine, I left the bottom 1-2 spring, and the 2-3 spring out, and left the original top 1-2 spring in place. At part throttle, it shifts nice and quick, but not neck-snapping. A WOT run will get the car sideways at 60mph, and that's with the stock 3.27 open diff. I also did mine to the highest setting, and after doing it that way, I'll never do the mild setting again. Also mine has been done for about 8K miles of daily driving now, with no problems breaking anything.
Click to expand...

Hey, how far from atco raceway are you?
 
Atco is quite a ways from me. I'm closer to englishtown. As for how hard the shift is, it isn't so hard that you think its going to break stuff, but it will get the car sideways when it shifts into 2nd. I really have no complaints about it at all, and after doing it this way, and having done the mild setup before, I will never go with the mild setup again.
 
OK sorry for being stupid about this but what is a J-Mod and what is is tccoa? I uderstand the reference to 1/2 and 2/3 being the gear shift servos.
Sorry I play with stroker 335 series with C-6's or Richmonds, not so much the compu cars. These mods sound like something I would like to do to my recently acquired 94

Thanks
 
tccoa is www.tccoa.com, the thunderbird and cougar club of america. The j-mod is a modification to the valve-body separator plate on the 4R70W trans. Basically it gives you nice firm shifts, like a shift kit, but it does it without jacking up line pressure or anything like that, and it is designed by one of the ford engineers who designed this trans, so it actually will make the trans last longer while improving shift feel and making the car faster. The 1-2 and 2-3 they are referring to are the accumulators. One of the things in the j-mod that is optional is removing one of the 1-2 accumulator springs, and removing the 2-3 spring. Doing this will make the shifts much firmer. Some people don't like that, but it really makes the trans feel solid instead of feeling like a slush-box. My 98, with the j-mod and otherwise completely stock, would get sideways shifting into second if I floored it. During normal sane driving, you could feel the shifts and you knew it wasn't stock, but it wasn't so much that it felt too harsh. I have since swapped a T45 into my car, but until I got around to that, I couldn't deal with the sloppy shifts of the stock 4R70. If you like to feel your car shift, and you care about performance at all, than the j-mod is definitely something you should do. If you want it to shift like a lincoln, than leave it alone.
 
Thanks, do you know of any detailed info or intructions for J-Mod, accumulator spring deleet on the net? I was wondering about removing accumulator springs when I was looking at a sheet listing all the spring PN's. I noticed that the Mustangs didn't have the upper spring on the 1/2 accumulator piston
 
Okay so I have my 95 Mark and have been reading about the JMOD. I was wondering if just removing one 1-2 spring and the 2-3 spring will make any difference without having to bore out holes.
 
Probably not a smart move cause the mod was designed by the Guy who designed the trans. I would bet he knows best.

My 1/2 piston lower spring was in 3 peices it might as well been not there and the 1/2 shift was very sluggish.

I bought the J-mod plate kit from Lonnie at BOC and installed both springs in the 1/2, but will be taking out the lower spring and possibly replacing the upper spring with original lighter weight upper spring. I still havent been able to figure out why the mustangs don't have a upper spring in the 1/2. Everyone says not take out the upper for the 1/2 in the Mark

The mod is worth every penny
 
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