The Official JMOD How-to Video by Rizzo 

The Jmod is of real benefit to your transmission-it's healthy for it to have this done. Removing the lower springs drastically reduces the clutch slip between gear changes, and the holes that are drilled make the transmission operate more efficiently and "breathe" easier in a hydraulic sense.

This video has an early-2000's documentary vibe to it. I like it.

You have the calm voice, patience and thoroughness of an expert instructor! Very rare qualities for a great teacher.

Something tells me this guy knows how to do more than just a j-mod.. There's no way in hell I'd attempt to do this, he didn't cuss or throw a single tool.. Lol. Great job.

Hey I have a 03 gt with the 4r75w. I just did your mod exactly how you did. took me about 2 hours total from start to finish. (I double checked with the video a couple times, to make sure I didn't miss anything!) I have to say, This is the easiest write up/video on this that I came across. I was dreading this mod because I have never did any work with auto trans before. I am very pleased with the outcome, GREAT under normal driving and EXCELLENT under hard acceleration.. BARKING TIRES FTW!

This procedure is called a J-mod properly because it was named after Jerry Wroblewski who participated in the design on the 4R70W Transmission. Since it's Jerry's Modification it's call the Jmod.

Still helping people to this day - or at least my happy ass. Great video man, thank you. One step closer to "not your grandpa's lincoln"

This man is the Bob Ross of J-mods

Wow. I have a 2003 Grand Marquis and it has comatose shifting. Literally got it from a retired school teacher who couldn’t drive anymore. 68,000 miles. I just want to thank you for a thorough instructional video WITHOUT swearing, throwing tools, and generally jackass behavior. I will try this when I do a transmission fluid and filter change

Thank you very much. I shot it twice, paid to have the supreme camera and editing done and worked thru a cold garage in Nov with a cold too. I'll pass on your comment to Andrew who did the above and my son who helped too.

I just rebuilt my transmission valve body and replaced the OD servo piston, rod and retaining ring. Your video gave me the confidence to do it and I made me save a couple of grands. Thanks a lot man, keep up with the great work!

You're the exact person I did this for. My first one took 8 hours and I had the same fears. I don't ever want another person to feel the same way that I did ever again. Thank you man.

Followed this video step by step and jmodded my 07 P71. The difference in the car is night and day. Transmission is so much more responsive and quick, and the WOT shifts are amazing! From here on, any 4R70/75 auto I own will be Jmodded. Thanks Rizzo!

I performed this exactly as shown in the video and all went great! I must say this is a great shift improver.. No neck snapping shifts. Proportionate to the throttle pressure. Just right.. also DO drill the plate for the reverse engagement. It eliminates that annoying delay! Great job on the video and thanks a million. I bought my VB gaskets and 8 check balls from the ford dealer and they were spot on.

Leave the bottom 2-3 out. For clarification : The lower 1-2 come out, The Upper 1-2 stays there... No one wants firmer down shifts....Steering wheels taste like ass.

The 4R70W transmission has a lot of clutch slip between gears and this is what creates that soft seamless shift most AARP members prefer, AKA "The Grandma shift." With the Jmod, you get a quicker shifting transmission with firmness you can control through throttle application and a longer lasting transmission too.

I’ve done a ton of work on my cars, including a trans swap and there is absolutely no way on Earth that I would ever attempt this lol. Great video man!

My 2004 Marauder has a tune and a very aggressive transmission shift. It is made even more pronounced by solid rear control arms and 4.10 gears. My 2004 Town car is a low mileage garage queen and completely stock chassis-wise. On both cars I use your transmission fluid pump technique to change the fluid occasionally especially in Florida where heat kills auto transmissions. I just consulted this video this morning for a fluid swap on the Lincoln. It only yields ~4 quarts so I did it three times and used a case of fluid. The color change is quite impressive!! Thank you for posting this and sharing your knowledge and expertise!

Started with this on my 06 P71, ended up rebuilding the whole trans. Turned out my direct clutch was smoked due to a internal hemorrhage caused by the case being worn where the ring seals on the output shaft ride. I had the case repaired with a steel sleeve and totally rebuilt it adding an extra friction and steel in the direct clutch and of course doing the J-mod. Totally different trans now, shifts much firmer and mileage went up, who knows how long the direct was slipping. Dig the 70's porn movie soundtrack on the video.

Very well done. I had this procedure done on the advice of my rebuilder on our Saleen S281 Budget a few years back. This mod, along with a couple other mods and and what the rebuilder called a Police Interceptor torque converter, really woke up the slush box. Hated having an auto trans in a Saleen, but at least the boss was happy and could drive the car frequently. Just picked up a CV LX Sport for my son. A well cared for one owner 211k mile car, I'm sure we'll be looking at a trans rebuild down the road. The car is SO clean that even a $1500 rebuild/mod on the trans is money well spent. Thanks for the great info and insight. Again, VERY well produced video! Sending it to my buddy who is a rear wheel drive platform engineer at FoMoCo!

Many thanks for walking us through with a detailed precise explanation. I just did the J-MOD on my 1997 Lincoln MARK VIII. I rebuilt the Trans and figured why not. While not exactly the same as the crown vic trans you are doing here. The principles are pretty much the same.Many thanks to the Thunderbird form as well. I used their layout to drill my plate.

Holy smokes, that was great. Thanks for making the time to show case this mod!

Did this a few months ago. My p71 shifts beautifully. I left the springs in but installed new ones.

Research the Softer Mustang Spring. Their trans was set for more of a Sport shift. This spring has less resistance than the stock FIRM CV/GMQ spring. NO ONE I have ever helped do one or done one on has asked for one after. I'd tell you to Do the entire process, Pull both bottom springs. If you do not like it, As shown, You can reinstall the bottom 1-2 with a simple pan drop.

Well I started off with the Jmod which turned into a full on transmission build, billet shafts and forward drum ( kept factory # of clutches), pump lube mod, force tail shaft lube mod, re worked Sonnex valve body with superior stage 2+ shift kit, billet adjustable OD servo, billet accumulator piston, new 1-2 accumulator piston, new overdrive and reverse band. replaced rear main seal with teflon, PA SFI flex plate (had to drill out converter holes to 31/64, put in new bearings and bushings teflon seals etc. New spicer u joints ( w/grease fitting). ARP Pro flex plate bolts, Mr gasket TC nuts, Ford Racing bell housing to block bolts, 2400-2800 stall converter. I busted the motor mounts getting the transmission out so new pioneer motor mounts. Royal Purple Max ATF, magnafine in line filter, SCT tune, all new sensors wiring harness valves etc, As soon as they are available Im ordering the SR performance transmission pan +2 QTS............All because I watched this Jmod video.

I am in the middle of this jmod on my 2003 p71, this video has helped ALOT! I have just gotten to 37:39 and am going to be calling it a night. I really believe that the hardest part of this whole mod was getting those two rear bolts out of the transmission pan to drop that pan...and I am no good with transmission gaskets so I hope everything seals back up alright. Thanks again!

Thanks for the great video! I have never been a Ford guy but I picked up a P71 for my daily and now I just want to play with it all the time.

Let me tell you about the powerful Thumbs Up Button! At first I was skeptical like you and then I did some research. Turns out not only did clicking Thumbs Up regrow my hair it also had effects likened to that on Axe Spray on the opposite sex but with out the harmful propellants! Also I noticed the same year I clicked Thumbs Up on this video we had a white Christmas,My son made Honor Roll two Trimesters in a row and my wife was promoted at work! You'd be crazy not to click Thumbs up!

Yes, This will work on your 1997. Go to TCCOA(DOT)com > Tech > Transmission > Modifying the Valvebody, Scroll down to DRILL SIZE CHART. I always preach to follow what Jerry said, So I would follow his write up which is what I followed.

amazing. this is perfect. I work on cars but never wanted to do this myself until this video. I will be doing this on my 95 mark viiii. thank you for the help.

Yes, and to anyone doing the 1-2 accum procedure the valve body does not have to come out. A C clamp or bottle jack can keep the accumulator from popping out. Search for TSB 97-11-11 on google for the correct springs for your car. Also, all these trans should use ONLY branded MERCON V to stop trans shutter! On some years you can remove the torque converter screw and easily drain all fluid. It was doable on my 95 tbird. I heard newer 2004?? units don't have it.

This video made me want to rebuild my trans and j-mod it. Very educational and thorough video. Well done 10/10

Already used this video for the j-mod, was a success but 1 year later my shifting selenoid gave out so I took it out and I took out a extra screw out and I went crazy not knowing what held it ton of videos but I remembered this one shows how to take out every bolt and it’s function I’m calm now

Just did mine. I ordered a new already modified throttle body so this made it super easy to follow. Because with the plastic harness

I put the original VB to this trans back in with the modified plate. It all seems to be working now. There must have been an issue with the other VB. I have no idea... All in all, Thank you for making the video. It is very informative.

Man I like the way you explain things and show it...now thats what I call a youtube channel bud.....

Nice work Rizzo. Your video is now part of a sticky on the LVC forum. I shared the video one day and everybody LOVED it! I can't believe the douche bag that had the tenacity to give you a thumbs down on this video. This video is 5 stars from start to finish!

Without a doubt, the best video and narrated how-to video I've ever seen. Well done and I think I will be doing this soon. Just have to get the car high enough to work under.

great video +++++++++++.Just got done w/mine no an '01' P71 crown vic w/135,000 mi.,what a difference.completely got rid of the slush box shifting.the shifts are not at all too hard.THANKS for posting it JJ

Thanks for posting Rizzo, well made video. I have performed a few Jerry mods back in the day (10+ years ago now) but havent had a Crown Vic in 5 or so years. Before this mod the car I just did shifted like "slipping on a banana peel". Now its crisp and a joy to drive.

A crown Vic transmission is pretty easy to take out and replace so doing this in the car would be an unnecessary gamble. It could be done, obviously, but constantly fighting gravity invites a mistake. Love the info though, very helpful and offered in a relaxed fashion that's easy to watch and learn

Thanks for this amazing video! If you have a pre-98 you should at least do the 1-2 accumulator in the vehicle. The piston was updated and the springs often break. It causes lots of 1=2 shift issues if the old parts remain.

AWESOME! Now I just need a spot to do it. Everybody watching don't forget to thumbs up. Makes it comes up faster on searches.

A 3/8th's drive extension and standard short 10mm socket is all I use for those. I know your cross member gets in the way. It's ok to push and pull some to get your extension past it. I come in from the side and slide the extension in between the C/M and the pan. It looks harder than it is.

an AWESOME video.Thankyou,I cant wait to give this a try in the near future.

This should have been done from the factory. Especially on P71s and Mustangs. Thanks for the great instructions, my P71 will be getting a JMod valve body here shortly

Thank you. I'm sufficiently warned as to the difficulty and specific needs of this modification. Thanks

I drilled all the hole just like in this video on my 2001 CV, also removed the 1-2 and 2-3 lower springs, perfect! i was afraid that remving the springs woukd make it harsh but the geezer glider motor keeps it just right, shifting is soooo way better!

Outstanding job brother. Can’t wait to do this on my ‘99 Grand Marquis. Thank you for such a thorough well executed video.

Excellent job! I don't have the trans to perform this procedure, but I feel like if I did, I could do it after watching this video.

Same as all the other years and models. A firmer shift, A clean Valve Body and a significant reduction in clutch slip between gears.

For the 1-2 Which is considered the "Lower' spring as I have read some have just used that spring but not both. Thanks

Really enjoyed this video in the music in the background as well

Great video. A good friend of mine owns a trans shop in the Detroit area. Builds some pretty mean Chrysler and other race trans. I'm local too, (Troy). I recently acquired a super-clean 1994 Crown Vic LX. Have 25,600 on the clock as of yesterday. My trans developed the nasty 40-45 mph shudder/vibration, I had the unit flushed and filled with Mercon V per the Ford TSB. About 1000 miles later, the shudder is back, somewhat gentler, but has got progressively worse in the space of 50 miles. Car has an at idle very subtle "lope" as if it had a performance cam. This is a departure from the Grandma car smooth idle. Something is up. It looks like tear-down trans time. I'm going to have my friend Tim rebuild it for me. I watched your video, love it! Way to share great info. Finally my last question: When performing the J-mod on a 1994 transmission, where can I find solid info on what holes to drill in the seperator plate and what size?

Thanks for the video , your help is greatly appreciated

I really appreciate the video. I'm doing a deeper rebuild right now, but this is a fantastic demonstration of the Jmod. I'll be interest to see if the shift kits I'm doing include this, which I think they do.

10/10 video. Thank you so much for this excellent presentation.

Do I do them for money? Ok dig, I have a few life changes coming up. I can not commit to anything right now. When all my plans come together I will put that out there. Thank you all who would trust me to work on your cars. I'll let you know when I can help you out. Cheers.

Jmod, i have a 2007 Interceptor with the 4R75E can i do the 1-2 Accumulator removal like the 4R70W? hope to hear back from you.

That tiny black filter can be discarded it's there from factory to suck up particulates in the break in procedure. Ford TSB says so. Just figured I'd throw that out there, a lil interesting tidbit :)

You should have a rubber plug on the bottom of your converter bellhousing. Pop that, and turn the crank till you see the bolt. When you are done, replace with a new bolt from Ford.

I'm getting ready to do this on my 06 P71. I just got another valve body off a 2010 out of the pick a part to do it on while I wait for my parts to arrive. Then all I have to do is swap valve bodies. I ordered an upgraded separator plate due to Ford's infinite wisdom of removing the reinforcement plate over the 2-3 servo creating two of the reasons the 4R70W and AODE transmissions go toast. Without that reinforcement there, the constant pounding of the 2-3 servo on the plate cause it to either crack or lift up causing a cross leak which engages the forward clutch pack when it shouldn't be engaged resulting in a toast transmission. The upgraded plate is thicker and comes with a little cap that goes over the "sombrero" end of the 2-3 servo to spread the force. The plate kit with new gaskets is around $45 which is cheap insurance against a $2,500 transmission rebuild. I'd recommend just getting an upgraded plate as cheap insurance against remortgaging your house to repair or replace your transmission.

I sure did reinstall the the 1-2 piston, Heck it's only out of the Trans for all of 7 seconds. If you're 1-2 doesn't look like the one I show then yes replace it. Mid '97 they made the change so I can't say if you have new or not. My 1997 CV had the improved one, See description for link to purchase 1-2 piston. I don't know anything about the Trans-go kit.

thank you Sir, great presentation by the way

Excellent video!

Looking at the gasket set for this jmod on eBay, they sell it with a valve body cover gasket also, but I don't see it removed in this vid. Safe to say I wont be needing it? Ill be watching this vid several times before I do it in case I missed something. It's ppl like u that give confidence to people to do shit themselves. Excellent vid bud.

Careful about removing the springs on the 1-2 accumulator. Very harsh shifts on engines producing

it MAY be safe to assume that's normal wear. You will never get a clean magnet after a rebuild or even a virgin trans.

very nice illustration! thank you for sharing...

Best video on jmod! I'm doing this to my old 94 mustang with an AODE. Have any recommendations for this model?

I wish I could find someone in Gainesville fl that can do this,CORRECTLY...

nice video rizzo

Great job on the video and thanks for sharing the info.

This is an amazing video Rizzo, thanks for taking the time to do it.

sweet job. thanks for sharing!

Weird question, but would you benefit from drilling the plate holes and not removing the accumulator springs?

Is there a link I can order the jmod for my 06 town car

CVN member HookedonCV had a chat with Jerry. The new hole instructions came from Jerry during that time. Changes must have been made to the plate to make those holes unnecessary to drill.

Just did this on my 99 grand marquis and even found the factory dipstick tube plug sitting in the pan. Sure brought that crappy slush box alive! shifts great, still not as firm as the C6 in my truck though.

My Aode is 93-95 I have a different separater plate. Do I still drill the same holes or hole size ?????

Oh yeah, you're good. I do this same procedure for the 2005 and up Crown Vics which have the 4R75E. The first 2005 I did was over 2 years ago. It's his daily driver and he's fine.

Great video. Had to replace the retainer ring for the O/D servo. When I lowered the valve body,never noticed the basket filter falling out. Well until I was completely done and was dumping my fluid....hey basket filter!!!! How important is that filter? Just thinking about those conjillion bolts to undo and keep up with!!!!! Aaaaaah!

My only question, and I have read the documents outlining the procedures (thank you for that!!!), what is the purpose of marking 1, 3, 6, 7, and 8 as there is no mention of them in the documents. I can see they are already larger in this plate than either of the suggested sizes.

Great video good sir!

Well, We Jmod our cars for a few reasons. 1 It creates a more exciting shift. 2 It eliminates the clutch slippage between gear changes. 3 The Valve Body is completely cleaned out and in a slightly more advanced version Shift Solenoids are replaced with stock parts from Sonnax, These parts wear out, So it's also Preventative Maintenance. 4 In some years All the Trans fluid is drained and replaced, Again more PM. ....... TBC..

I did this about 7 years ago to my 2004 P71 all by using this video on my iPad step by step. Sadly sold that car about three years ago (biggest regret). Looking at grabbing a 2010 Grand Marquis this week that is in pretty damn good shape with 90,000 miles on it. Can I follow this exact video once again for that same year?? Man, idk if I have it in me to do it again, but I know I want to.

Yes, Easy though. Once you have the car up and have room crawl under there with your feet out the drivers side. Get a good breaker bar or at least a 1/2 drive ratchet and an 18mm Socket. Remove the black rubber plug you see at the bottom of the bell housing, Feel first,you may be lucky and see the drain,If not use the ratchet and turn the motor by hand Clockwise with your right hand and leave your left in the hole and wait for the drain to come around. 7/16th socket for the drain plug

It's a blown trans used for display purposes. It's a film prop homie. In fact its still in my garage with 4 empty beer cans on it.

The music in parts gives me anxiety. Lol but thank you this video is very helpful

Amazing video!! Outstanding instruction !!!!

Very good points to bring up. Link to part in description now! $9 part too!

Thank you for this! Saved to favorites!

You've driven an Automatic transmission car before right ? The time it takes to shift between gears, We've just shortened it and made it more exciting for the driver by following directions from a person involved in this transmissions design.

This music makes me feel like I'm watching Law & Order SVU.

Awesome step by step video buddy. Love it

11 Years ago. Man! Congrats - still awesome. How/Does this change with Sonnax Mods?

5:35 I have a question: if it is not healthy enough for the j-mod what is recommended to do next? My plan is to rebuild a 4r70w completely and do the j-mod. Excellent video thus far.

Up close and personal. This is the same transmission for the 1999 Mustang GT...correct? Let me congratulate you on such a good job.

Would this work on a 1998 mustang gt automatic?