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510paesan
08-28-2015, 04:24 PM
Recently purchased a '03 300A. Odometer is at 106k. Very healthy, noticed no problems so far. New member to this forum, and so far this site has been VERY helpful. Thank You All

Was reading up a lot and thinking of doing the jmod on my 4r70w myself. Im a transmission mechanic by trade, but not in the sense that you esteemed gentleman may think. I'm an A&P mechanic for a FAA repair station, performing diagnostic repair or overhaul on gearboxes that are otherwise known as CSD's and IDG's.

I've downloaded an old .pdf from the TCCOA site, and watched rizzos video on youtube, and read many, many posts on this forum and others regarding this mod.

I've purchased my new gaskets, new deep pan, was planning on getting all the Sonnax goodies: servo pin kit, regulator kit, boost valve kit, new Superior Tuff plate, and just knocking this out at work one Saturday morning (off the clock, of course)

What should I be aware of here? Simply removing springs and drilling a bunch of holes seems like it could cause damage. Thoughts, suggestions would be much appreciated.

RubberCtyRauder
08-28-2015, 04:54 PM
The Jmod was invented by a ford transmission engineer , Jerry Wrobleski or something like that. It lessens friction by speeding up the shift. The only time it might be a trouble is if you wot from a stop on wet roads. The 1-2 shift can get squirrelly.

chief455
08-28-2015, 04:58 PM
don't know the video you watched, but I've read / seen enough info to feel comfortable doing it.
pretty much a shift kit - drilled seperator plate passages and spring changes. nothing new.
go for it.

RubberCtyRauder
08-28-2015, 05:03 PM
The vid was made by member Rizzo on CVN. He has personally done over a dozen of them . It's a YouTube vid. Link should be a sticky thread over on CVN

fastblackmerc
08-28-2015, 05:17 PM
Recently purchased a '03 300A. Odometer is at 106k. Very healthy, noticed no problems so far. New member to this forum, and so far this site has been VERY helpful. Thank You All

Was reading up a lot and thinking of doing the jmod on my 4r70w myself. Im a transmission mechanic by trade, but not in the sense that you esteemed gentleman may think. I'm an A&P mechanic for a FAA repair station, performing diagnostic repair or overhaul on gearboxes that are otherwise known as CSD's and IDG's.

I've downloaded an old .pdf from the TCCOA site, and watched rizzos video on youtube, and read many, many posts on this forum and others regarding this mod.

I've purchased my new gaskets, new deep pan, was planning on getting all the Sonnax goodies: servo pin kit, regulator kit, boost valve kit, new Superior Tuff plate, and just knocking this out at work one Saturday morning (off the clock, of course)

What should I be aware of here? Simply removing springs and drilling a bunch of holes seems like it could cause damage. Thoughts, suggestions would be much appreciated.nj

If you read up on the reason for the J-Mod you'll find it will actually extend the life of the tranny.

Logizyme
08-28-2015, 05:22 PM
You are not adding any holes, rather just opening some up a bit so more fluid flows through. Traditionally JMOD consists of opening a select few holes on the separator plate and removing the 1-2 and 2-3 accumulator springs.

Having modified about 10 cars, and daily'd 3 different variations on the mod (all 2003's BTW) I can say that spring removal is excessive for anything on the street. Seperator plate modification will result in a more throttle based change, while spring removal is just a neck breaking shift even at the lowest of throttles.

What I will say most about it is spring removal will have you spilling your coffee on your way to work and make your friends ask you whats wrong with your transmission.

Alternatively there are softer springs you can use, and I would suggest looking into them. While I would not recommend installing any shift kits, allot that you might find on ebay contain softer 1-2 and 2-3 springs, I run a couple of springs out of an ebay shift kit myself. Something to think about if you want more that stock springs but less than no springs.

Also the JMOD does little to nothing for OD and 3-4 shifts. Doing some extra work and replacing the OD servo piston with a Sonnax kit will help your 3-4 shifts feel closer to your 1-2 and 2-3. The Sonnax servo piston includes a slot with an oring in it for better sealing and includes a preload washer that is optional to preload the inner spring increasing the OD band application even more. This is additional labor and special attention needs to be paid to ensure the piston is properly located on the band when going back together.

I like that you are already thinking about the sonnax valves, not only is replacing wearing valves a good idea but most the sonnax parts are improved designs and some give spring/hole size options to customize how aggressive you want it.

Currently the best setup I have come across is shift kit 1-2 2-3 springs, Sonnax OD piston kit, Sonnax valves, conservative on the separator plate hole sizing. My hot date in the passenger seat is none the wiser when I drive modestly, but when I am driving like a mad man it is fast and firm though all gears.

I've seen allot of people to the traditional mod, just to realize they want to put the springs back in a few months later when the ridiculous shifts becomes just annoying.

Logizyme
08-28-2015, 05:24 PM
nj

If you read up on the reason for the J-Mod you'll find it will actually extend the life of the tranny.

arguable. I'm not saying one way or another, but don't believe everything the internet says.

88grandmarq
08-28-2015, 10:18 PM
sent you a PM...

MyBlackBeasts
08-28-2015, 10:28 PM
Recently purchased a '03 300A. Odometer is at 106k. Very healthy, noticed no problems so far. New member to this forum, and so far this site has been VERY helpful. Thank You All

Was reading up a lot and thinking of doing the jmod on my 4r70w myself. Im a transmission mechanic by trade, but not in the sense that you esteemed gentleman may think. I'm an A&P mechanic for a FAA repair station, performing diagnostic repair or overhaul on gearboxes that are otherwise known as CSD's and IDG's.

I've downloaded an old .pdf from the TCCOA site, and watched rizzos video on youtube, and read many, many posts on this forum and others regarding this mod.

I've purchased my new gaskets, new deep pan, was planning on getting all the Sonnax goodies: servo pin kit, regulator kit, boost valve kit, new Superior Tuff plate, and just knocking this out at work one Saturday morning (off the clock, of course)

What should I be aware of here? Simply removing springs and drilling a bunch of holes seems like it could cause damage. Thoughts, suggestions would be much appreciated.


http://www.mercurymarauder.net/forums/showthread.php?t=82460

Not drilling holes, making existing holes larger.

Will not cause damage, will actually reduce trans wear. The jmod speeds up clutch pack engagement which reduces clutch plate slippage time which reduces wear. The longer the pack slips to smooth out the shift the more the clutch material wears = shorter trans life.

This is easiest & cheapest mod you can do to bring on more smiles per mile. Do it & don't look back.

If you ever decide you don't want it, $4 and it's gone (use the HD new plate for jmod & keep the factory plate unmolested to revert if needed).

loud2004marquis
08-29-2015, 04:51 AM
Have done two j mods to my own cars with the 1-2 & 2-3 spring removal and drilling out the holes, shifts nice to me :) I only used the PDF from the Tocca site as a guide. Not hard to do at all. Have fun!

BigM460
08-29-2015, 05:14 AM
Would recommend not removing the 1-2 accumulator spring. The slambing 1-2 shift without the spring gets old after a couple weeks.

Bad_S55
08-29-2015, 05:30 AM
I don't think I've heard anything on this before, but do you make the holes in the gasket bigger too or do you just put those in?

Marauderjack
08-29-2015, 06:31 AM
Would recommend not removing the 1-2 accumulator spring. The slambing 1-2 shift without the spring gets old after a couple weeks.

^^^+10^^^!!:eek:

Mine actually shifted so HARD I put a Mustang spring back in......still pretty hard but we softened it in the tune below half throttle.......still hard at WOT but smoooth due to wheel spin!!:burnout::beer:

The worst part of doing th J-mod is the "Trans Fluid Shower"....quite messy!!:argue:

510paesan
08-29-2015, 07:08 AM
What I will say most about it is spring removal will have you spilling your coffee on your way to work and make your friends ask you whats wrong with your transmission.

Alternatively there are softer springs you can use, and I would suggest looking into them. While I would not recommend installing any shift kits, allot that you might find on ebay contain softer 1-2 and 2-3 springs, I run a couple of springs out of an ebay shift kit myself. Something to think about if you want more that stock springs but less than no springs.



Well I definitely don't want to have myself or any hot date spilling anything on my leather. do you have p/ns for springs that you would recommend?


I don't think I've heard anything on this before, but do you make the holes in the gasket bigger too or do you just put those in?

yes, you have to enlarge the corresponding holes on the top gasket

510paesan
08-29-2015, 07:12 AM
sent you a PM...

Thanks for the pm. From going through a lot of YOUR old posts I was able to find the correct p/n's for the kits I need from Sonnax

510paesan
08-29-2015, 07:17 AM
The worst part of doing th J-mod is the "Trans Fluid Shower"....quite messy!!:argue:

That's Ok. . eagerly awaiting the baptism. . Can't be any worse than used, burnt up old turbine oil, which I have to deal with on a 9 to 5 basis

chief455
08-29-2015, 08:24 AM
I got a reputable trans builder guys j-modifed Marauder seperator plate that is used, but never on my car.
Do I just remove / replace this plate for my stock one for j-mod minus hard shift-no spring mod? (provided said plate is modded correctly)
that simple?

not intended thread hijack - related question.:)

fastblackmerc
08-29-2015, 09:01 AM
Yes. You'll also need new gaskets and you'll have to enlarge the corresponding holes in the gaskets.

Logizyme
08-29-2015, 09:55 AM
Well I definitely don't want to have myself or any hot date spilling anything on my leather. do you have p/ns for springs that you would recommend?



yes, you have to enlarge the corresponding holes on the top gasket

Most of any Ford part numbers are buried deep in CVN threads. But I think I pulled springs from this kit: http://www.ebay.com/itm/VALVE-BODY-SHIFT-CORRECTION-PACKAGE-KIT-AODE-4R70W-SUPERIOR-TRANSMISSION-transgo-/250987430265?hash=item3a700441 79&vxp=mtr

That kit has two different stiffness 1-2 springs and a softer 2-3 spring so you can decide exactly how aggressive you want to go. It also contains the drill bits you'll want for separator plate modification. I would NOT suggest using the valve's or valve body springs from this kit unless you are aware of their function and make an informed decision to use them.

510paesan
08-30-2015, 09:45 AM
Most of any Ford part numbers are buried deep in CVN threads. But I think I pulled springs from this kit: http://www.ebay.com/itm/VALVE-BODY-SHIFT-CORRECTION-PACKAGE-KIT-AODE-4R70W-SUPERIOR-TRANSMISSION-transgo-/250987430265?hash=item3a700441 79&vxp=mtr

That kit has two different stiffness 1-2 springs and a softer 2-3 spring so you can decide exactly how aggressive you want to go. It also contains the drill bits you'll want for separator plate modification. I would NOT suggest using the valve's or valve body springs from this kit unless you are aware of their function and make an informed decision to use them.

Got it, Thank you sir!

MyBlackBeasts
08-30-2015, 01:38 PM
Would recommend not removing the 1-2 accumulator spring. The slambing 1-2 shift without the spring gets old after a couple weeks.


That's my favorite thing!

If driving normally there is very little slamming but move throttle a little more and the fun begins!

Appeals to the same fun receptor in me that enjoys dumping the clutch & banging gears or roller coaster rides! :banana2:

Marauderjack
08-30-2015, 01:40 PM
That's my favorite thing!

If driving normally there is very little slamming but move throttle a little more and the fun begins!

Appeals to the same fun receptor in me that enjoys dumping the clutch & banging gears or roller coaster rides! :banana2:

UNTIL.......ya try to drive it in the RAIN!!:eek:

MyBlackBeasts
08-30-2015, 01:43 PM
I don't think I've heard anything on this before, but do you make the holes in the gasket bigger too or do you just put those in?

Some of the holes in gaskets are already big enough for the drilled holes, some require a little Exacto knife surgery.

When done drilling, lay gasket on plate & you'll see what needs tweaking. Just cut carefully and keep circular - no points.

Eazy Peezy!

MyBlackBeasts
08-30-2015, 01:48 PM
UNTIL.......ya try to drive it in the RAIN!!:eek:

Drive in the rain all the time. Daily driver.

409hp Trilogy, 12" wide MT drag radials too.

No problems, just have to adjust driving style to match conditions.

justbob
08-30-2015, 02:02 PM
Softer springs are lame. Remove them, dial in your line pressure accordingly, and drive the snot out of it. No issues here for the three years or more I had it before converting to the next best thing.


Builder Of Badassery

MyBlackBeasts
08-30-2015, 02:20 PM
...converting to the next best thing.

So jealous...:depress:

How awesome would it have been if they came factory with Manual trans! :cloud9:

Ahhhh... vehicles from my childhood that I always dreamed of owning/driving. 4000lb massive muscle sled with a bigblock & MT... :burnout:

Marauderjack
08-31-2015, 02:45 AM
Drive in the rain all the time. Daily driver.

409hp Trilogy, 12" wide MT drag radials too.

No problems, just have to adjust driving style to match conditions.

AMEN......snappy downshifts are a killer!!:eek:

88grandmarq
09-05-2015, 11:11 AM
Recently purchased a '03 300A. Odometer is at 106k. Very healthy, noticed no problems so far. New member to this forum, and so far this site has been VERY helpful. Thank You All

Was reading up a lot and thinking of doing the jmod on my 4r70w myself. Im a transmission mechanic by trade, but not in the sense that you esteemed gentleman may think. I'm an A&P mechanic for a FAA repair station, performing diagnostic repair or overhaul on gearboxes that are otherwise known as CSD's and IDG's.

I've downloaded an old .pdf from the TCCOA site, and watched rizzos video on youtube, and read many, many posts on this forum and others regarding this mod.

I've purchased my new gaskets, new deep pan, was planning on getting all the Sonnax goodies: servo pin kit, regulator kit, boost valve kit, new Superior Tuff plate, and just knocking this out at work one Saturday morning (off the clock, of course)

What should I be aware of here? Simply removing springs and drilling a bunch of holes seems like it could cause damage. Thoughts, suggestions would be much appreciated.

For a stock to mild Marauder do this:

replace the pressure regulator valve with Sonnax valve - 76948-09
replace boost valve with Sonnax valve - 76948-02K
replace OD regulator valve with Sonnax valve - 76948-29K
replace the 1-2/2-3 shift valve end plug with Sonnax end plug - 76999-MED (comes in a pack of 3)
replace the separator plate with Superior "TUFF" plate - K092

drill to new plate:
hole 1 = .161" - #20
hole 2 = .1015" - #38
hole 3 = .180" - #15
hole 4&5 = .113" - #33
hole 6 = .161"
hole 7 = not used
hole 8 = not used
hole 9&11 = .125" - 1/8"
hole 10 = .089"

DO NOT REMOVE ANY OF THE ACCUMULATOR SPRINGS !!!!

assemble valve body with new gaskets.
Use a hollow punch and enlarge holes 4&5 in the gasket to match new holes you drilled.

install new valve body with new filter and re-fill with 10 qts of Mercon V fluid.

READ HERE --> http://www.mercurymarauder.net/forum...ad.php?t=96760

510paesan
09-05-2015, 09:07 PM
Performed j-mod this weekend. I have no 4th gear aka overdrive during first test drive. I turned overdrive off and was able to see that 1-2, 2-3, shifted beautiful. . . What wasn't so beautiful was what came next. . .free wheeling and watching my rpm rise . . Very annoying. In sonnax Od servo pin kit p/n 76833e I noticed their servo pin differs from the oem one. It has an additional slot for an o-ring that sits closer to the tip of the pin. I'm wondering if this o-ring is causing the pin to become lodged in the bore... Thus no overdrive?

88grandmarq
09-06-2015, 11:43 AM
From your post, I am going to assume you installed Sonnax OD servo pin with 2 o-rings.

Most likely the OD band fell out of place when you removed the servo and the new servo pin did not engage the band when you re-installed it.

You will need to take everything back apart, remove the OD servo, use a hack saw blade and jamb it up in the case to hold the OD band in place so the pin will contact the OD band anchor. With a flash light, you should be able to see the band anchor through the Servo pin hole in the case. Once you have confirmed the band is in place, lube the o-ring on the new OD pin with clean ATF or vaseline and install the pin the hole and secure the snap ring.

http://i1033.photobucket.com/albums/a414/88grandmarq/Transmissions/band_out_zpspy0xhvor.jpg

http://i1033.photobucket.com/albums/a414/88grandmarq/Transmissions/blade_zpsug6kdutq.jpg

http://i1033.photobucket.com/albums/a414/88grandmarq/Transmissions/push_zpsfrtrdg43.jpg

510paesan
09-06-2015, 11:27 PM
yea I had figured it out rather quickly this morning. im now seeing this and its sunday night. I used a pick to wind the od band back into place as was able to push the od servo back into place with a jack. felt pretty embarrassed when I finally figured it out, after having a beer and going under there with a flashlight