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  #1  
Old 03-21-2008, 04:50 PM
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Default j mod

so is the j mod for auto trannies or what. i think that it is but it did not really say.

if so i think that im going to do it.
this is like the only one i found.
http://www.vapauto.com/jmod.htm

and i guess ill do the spacer too.

http://www.vapauto.com/spacers2.htm

what do u guys think.
 
  #2  
Old 03-21-2008, 04:56 PM
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yes its for auto's. It basically firms up the shifts however you can do all of that by just buying a hand held tune and reflash the computer to change shift points and firm them up
 
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Old 03-21-2008, 05:00 PM
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Originally Posted by Dave04Mustang
yes its for auto's. It basically firms up the shifts however you can do all of that by just buying a hand held tune and reflash the computer to change shift points and firm them up
not the best way to do it though. Jmod is a lot better on the tranny.

from what i understand the guy (jerry) origionally designed a pretty good auto tranny, however, ford thought it was too agressive and tamed it down a bit by sizing down some of the holes, which is why our trannys feel a bit confused sometimes. The jmod puts it back to the origional specs.

total in parts it costs you like 15 bucks to do it, i havent done it, always wanted to but im hesitant to start monkeying around in there.

research the **** out of it, there are some bad instructions floating around, and more than one person jacked up thier transmission, but if you do it right apparently it makes a world of difference.
 
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Old 03-21-2008, 05:12 PM
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i was just gona get the parts and take it to a shop. im not gona start messing aroung with the tranny me self.
 
  #5  
Old 03-22-2008, 09:21 AM
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Swapping a valve body is very very simple. If you own an hanyes or chilton manual it has the direction on pulling it out i do beleive and its very simple. A tuner is the worst way to firm upo shifts as it makes the front pump work harder and will wear it down over time (been there done on that on my old F150). A valve body mod is a much better way to firm the shifts back up. There is a write up on this all over the internet aswell to show you how simple it is.

This is from one of our forum members:
http://www.dndgarage.net/jmod.htm
 
  #6  
Old 03-24-2008, 08:50 AM
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so this spring im getting the mustang detailed. then should i go for the j mod or the exaust first. im on kinda a tight buget.
what do u guys think
 
  #7  
Old 03-27-2008, 05:58 PM
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so i want to have the j mod the intake manifold spacer and the mac v6 cat back exaust all befor ford nationals in carlisle. so im gona shell out a few bucks till then i guess.
but that might be my hole mod budget for the summer.
mabe
 
  #8  
Old 03-27-2008, 06:14 PM
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If your going to do it sooner or later, and have the money now, go ahead and do it. You will have more time to enjoy it.
 
  #9  
Old 03-27-2008, 07:02 PM
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if i buy all-J-Mod Kits for the 4R70W ,99-04 3.8L Splitport Mustang Spacers and The Windstar Intake Kit (99-04 3.8 Mustangs) will i have more hp and torque? if i buy all three?
 
  #10  
Old 03-27-2008, 08:17 PM
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The jmod can be done for a few dollars in parts and then new fluid and filter. Its a must do for an auto car and you should add a tranny cooler to as heat kills auto trannys. Best $50 mod for an auto car is a tranny cooler.
 
  #11  
Old 03-27-2008, 09:08 PM
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Originally Posted by Redrum
if i buy all-J-Mod Kits for the 4R70W ,99-04 3.8L Splitport Mustang Spacers and The Windstar Intake Kit (99-04 3.8 Mustangs) will i have more hp and torque? if i buy all three?
from what i added up its like 22/lbs
of torque and like 13 hp. and faster harder shifts.
 
  #12  
Old 03-27-2008, 09:09 PM
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Originally Posted by spike_africa
The jmod can be done for a few dollars in parts and then new fluid and filter. Its a must do for an auto car and you should add a tranny cooler to as heat kills auto trannys. Best $50 mod for an auto car is a tranny cooler.
i didnt see any of those around sounds like something to look into. ware can i find one.
 
  #13  
Old 03-27-2008, 09:14 PM
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Tranny coolers can be found on Summit, Jegs, Ebay, alot of sites. There's not really a certain one for Mustangs, just universal. http://store.summitracing.com/partde...5&autoview=sku
Recommended.
 
  #14  
Old 03-27-2008, 09:34 PM
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cool thanks
 
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Old 03-28-2008, 08:07 AM
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Originally Posted by Redrum
if i buy all-J-Mod Kits for the 4R70W ,99-04 3.8L Splitport Mustang Spacers and The Windstar Intake Kit (99-04 3.8 Mustangs) will i have more hp and torque? if i buy all three?
I don't believe the intake spacer for the split port upper will work with the Windstar upper.
 
  #16  
Old 03-28-2008, 09:13 AM
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oh yeah i didnt think of that
 
  #17  
Old 03-28-2008, 09:28 AM
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You could proably make it work. Since the Windstar upper bolts to the Mustang lower, and the spacer goes between. You will proably need longer bolts, alignment pegs, etc.
 
  #18  
Old 04-02-2008, 06:29 PM
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so you guys with the j mod. how is it working for you. and what kind of change did u notice an ware did u notice it.
 
  #19  
Old 04-04-2008, 11:29 AM
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Just another vote for the trans cooler. Easy to install & you can swap it out to another vehicle if you ever sell yours.
 
  #20  
Old 04-04-2008, 04:59 PM
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With the J mod it will shift firmer and faster then stock. It will most likely bark the tires on the 1-2 shift at WOT which is always fun. But it wont be so harsh that daily driving will suck.
 
  #21  
Old 04-04-2008, 09:31 PM
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k thanks guys im gona get it.
and im looking at tranny coolers too. thanks for the heads up.
 
  #22  
Old 04-05-2008, 04:01 PM
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Make sure you get a cooler that is a complete kit and has lines, fitting, and mounting hardware you dont want to be looking for that ****.
 
  #23  
Old 04-05-2008, 05:37 PM
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oh ok should i do the j mod and tranny cooler all at once or can i do one first and then the other.
 
  #24  
Old 04-05-2008, 06:12 PM
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If your going to be doing tranny work just do them both its easy to do a cooler, just mount it, unhook one line running out of the stock cooler from the radiator then connect it to the cooler hook the cooler line into the radiator and tighten claps, its that easy. The J-mod will take you if you have never done tranny work i would say around 3-4 hours taking your time looking at instructions etc.. over all both are easy and should be done to any auto car. Heat is the worst thing for an auto tranny minus neutral drops.
 
  #25  
Old 04-05-2008, 06:13 PM
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It would be better to do it all at once, since they're going to have to pull the tranny might as well get it all done at once.
 
  #26  
Old 04-05-2008, 06:14 PM
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You don't have to pull the tranny all you have to do is drop the tranny pan and unbolt the valve body, easy to do.
 
  #27  
Old 04-05-2008, 09:07 PM
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Originally Posted by spike_africa
If your going to be doing tranny work just do them both its easy to do a cooler, just mount it, unhook one line running out of the stock cooler from the radiator then connect it to the cooler hook the cooler line into the radiator and tighten claps, its that easy. The J-mod will take you if you have never done tranny work i would say around 3-4 hours taking your time looking at instructions etc.. over all both are easy and should be done to any auto car. Heat is the worst thing for an auto tranny minus neutral drops.
Thats how I routed mine, I installed it behind the grill in front of the radiator.
 
  #28  
Old 04-06-2008, 04:20 PM
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what is a neutrol drop?
 
  #29  
Old 04-06-2008, 04:22 PM
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Just what it sounds like. You have the car in N then rev the motor and throw it in D. This is bad for any auto car. Dont do it.
 
  #30  
Old 04-14-2008, 02:44 PM
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Wheres the best place to purchase the J-mod from? and is buying a tranny cooler nessicary?
 


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