Just did the J mod today. Sorry no pics since I want to finish the J Mod asap in a snow day..

I used the J mod kit bought from 88grandmarq which included a Super Tuff pre-drilled separator plate, a Sonnax Overdrive Servo Regulator (http://www.sonnax.com/parts/2402-overdrive-servo-regulator), a Sonnax Boost Valve (http://www.sonnax.com/parts/2393-boost-valve-kit) and some other stuff (filter, gasket...). Also I bought 12 qt Mercon LV from ford dealer ($5.1*12=$61.2, cheaper than Amazon) and I used 10 qt.

I did not remove any of the springs (1-2 and 2-3). The result is awesome, the 1-2 and 2-3 shifts firm but not harsh. OD is firmer than before but not uncomfortable.

The most challenging thing was doing J mod in a snow day..My hands were almost frozen. However I'm happy with the result. By doing the J mod I know that my transmission (actually valve body) is in good condition.

Overall, very happy. Thanks 88grandmarq!

glad it worked out.

Nice!

I was going to make a post about this, but since the vehicle owner beat me to it, i will expand on his post.

OP contacted me in December about a Jmod on his car. Originally we were going to meet in person and I do the work, but our schedules didnt allow for this. Instead, I shipped the parts for him to install. Parts included in the kit I shipped; pre-drilled Superior Tuff plate, new sonnax shift valves, new gaskets and filter. He requested the transmission shift firmly, so several of the holes were drilled larger than normal.

Hole 1 - .160
Hole 2 - .113"
Hole 3 - .180"
Hole 4&5 - .116"
Hole 6 - .161"
Hole 7 - .093"
hole 8 - Not used
hole 9&11 - .125"
hole 10 - .093"





Ford updated the pressure regulator valve in 2010, which eliminates the wear normally seen on older valve bodies. in this case the Sonnax replacement valve is not needed on 2010 or 2011 valve bodies


Since holes 4&5 and being drilled larger than .093" its is necessary to open the hole in the gasket to match the new larger hole. I use a hollow punch for this.

here is the missing picture from my post earlier.

What do you use to sand/deburr the plate after drilling it? That plate is so thick that it leaves more material to clean up than when drilling an oem plate.

i use an air powered sanding tool with a 2" disc. makes quick work of deburring the holes

I thought I read that 05 and newer p71's pretty much had the jmod done stock. Or that the newer vics wouldnt benefit from the mod as much as the older vics.
Is this true?

I got the gaskets hanging in my garage from a few years ago but never did it on my 07.....
Im buying a 2010 p71 in the morning and wondering if the jmod would be worth the effort?

completely un-true. all of these transmissions benefit from the Jmod. Some of the holes in the plate on the 2004 and up transmissions are already larger from the factory, but not all of them. all of these transmissions suffer from pressure loss in the valve body from worn pressure regulator valves and wear on the factory separator plate where the 2-3 accumulator presses against the plate. doing the Jmod, replacing he separator plate and replacing the shift valves eliminates the pressure leaks and makes the transmission shift better. 2005 and up transmissions have better EPC solenoid, so it already has more pressure. For a stock vehicle I typically drill hole 2 for the 1-2 shift smaller and drill hole 4&5 and 9&11 larger than what the Jmod spec calls for. From my experience, this creates a crisp, consistent shift with out being annoying