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You wont regret it. I have about 10K miles on my 95 Tbird since I did the Jmod and really like it. Nice firm shifts and so much better than stock.
Good luck with yours.
 

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Almost time to drain and refill the merc V in my '94 and was thinking about doing the jmod and maybe a new torque converter. How much does Robert P charge for a valve body jmodded with the updated pistons? Also the upgraded torque converter is out of a mark viii right?
 

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I had the J-mod done in both my 95 T-Bird and 96 Cougar. It worked great in both cars, except it made the 96 WOT shift at 4000 RPM. Anyone else have that happen?

My 95 still shifted at 5200 afterwards. I want to get it done on my new 97, but I don't want to have to get a tune just to restore my 5200 shift point.

Al
 

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There shouldn't be anything in the tranny that would change that, unless you are way off on the VSS gear.

Gear shifts are based on rpm, mph, and TPS in our cars, unless you have an aod with a TV cable...

I recently had my car aligned, and the guy who drove it said, "the shift pattern is strange".

Yeah, I did that myself, lol.

They drive like a manual, with my tune. :rofl:

EDIT: The difference in rpm could be wear, and the 96 had upgrades.
 

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RobertP did the J-mod on both cars, so everything was set up properly. He didn't sound surprised when I told him about the 4k WOT shift point, he said it happens to the 96-97's sometimes. He said he could fix it with a tune.

Al
 

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The j-mod will always make the trans shift at a lower rpm, but I'm surprised it moved it up that much. When the trans shifts, it takes some time for the accumulators to fill with fluid and the shift to be completed. The computer knows how much time this takes, and how long it takes for a stock car to accelerate, so it commands the shift slightly before it wants it to be completed. For example, if it wants it to shift at 5200rpm, it may command the shift at say 4600rpm so by the time the shift is completed, you are at the 5200 where it wanted. If you cut the amount of time it takes to complete the shift in half, then now that same shift would happen around 4900rpm. The reverse effect happens when you improve the acceleration of the car, say with steeper rear end gears. The rpms now climb faster than the computer is expecting, so if you command the start of a shift at the same 4600rpm that used to complete at 5200, it may now not complete until 5400. This is why on some cars putting steeper rear end gears can cause the engine to hit the rev limiter on WOT 1-2 shifts.
 

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Who is RobertP, and where can I contacted him or order this kit, I have always hated how my car shifts and I think this might be my answer.
 

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I know this is an old thread but I have a question and this may be where I can get an answer. I have done a J-mod on a 97 Tbird and was very pleased 28th it. Now I have a 2000 explorer with a 4R7OW transmission. It's used for daily driving, towing a camper, and the occasional trip off road. I think a J-mod would benefit it. Are there any differences between the 97 trans and the 2000 I should know about?
 

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Only advice I have about that is go for the mild setting. I did a full j-mod on my buddy's wife's explorer, and with the AWD there was no give when it shifted so hard, and after about 15K miles, it cracked the planetary housing.
 

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Only advice I have about that is go for the mild setting. I did a full j-mod on my buddy's wife's explorer, and with the AWD there was no give when it shifted so hard, and after about 15K miles, it cracked the planetary housing.
Good to know. I was wondering the same thing about my AWD 97 Mountaineer.
 

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Be careful how aggressive you go with a stock torque converter and towing. The stall speed on that converter is fairly low and that'll make any changes you do more noticeable.

But yes, it'll help. On a 2000 you will follow the instructions as they are.

If you need anything for it let me know

D
 

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Loved the J-mod on my 95, it shifted WOT at 5200 and barked 2nd dirty.

Hated the J-mod on our old 96, caused it to shift WOT at 4000. I don't like mods that require another mod - ie: a tune to restore the shift points. Turns a $200 (installed) job into about a $600-700 job all said and done.

Al
 

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Don't know why but I'm just not getting any emails about posts to TCCoA like I used to.. anyway.

Only advice I have about that is go for the mild setting. I did a full j-mod on my buddy's wife's explorer, and with the AWD there was no give when it shifted so hard, and after about 15K miles, it cracked the planetary housing.
I've already upgraded my Explorer from AWD to 4WD with a BW4406 Tcase. Although that really wouldn't change how much "Give" there is in the driveline. I'd planned on going with the mildest J-Mod as I'm not going to race it, I just want quicker firmer shifts to help reduce slip and heat buildup.

Darrin said:
Be careful how aggressive you go with a stock torque converter and towing. The stall speed on that converter is fairly low and that'll make any changes you do more noticeable.

But yes, it'll help. On a 2000 you will follow the instructions as they are.

If you need anything for it let me know
I've been reading on the Explorer Forum that the truck transmissions may not respond the same as a car transmission. I'm hoping that those who say the truck wont respond the same are those that tried more extreme J-mods. Sure would like some reassurance that I can do the J-mod to the Explorer with no ill effects. When you say "follow the instructions as they are" do you mean as written in the tech article? That's what I followed when I did the Tbird years ago.
 

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Don't know why but I'm just not getting any emails about posts to TCCoA like I used to.. anyway.



I've already upgraded my Explorer from AWD to 4WD with a BW4406 Tcase. Although that really wouldn't change how much "Give" there is in the driveline. I'd planned on going with the mildest J-Mod as I'm not going to race it, I just want quicker firmer shifts to help reduce slip and heat buildup.



I've been reading on the Explorer Forum that the truck transmissions may not respond the same as a car transmission. I'm hoping that those who say the truck wont respond the same are those that tried more extreme J-mods. Sure would like some reassurance that I can do the J-mod to the Explorer with no ill effects. When you say "follow the instructions as they are" do you mean as written in the tech article? That's what I followed when I did the Tbird years ago.
Regarding your email notifications, I found out the email I had registered with the site was no longer working because I never sent anything through it, only received, so my ISP canceled it for lack of use. Verify your registered email is current, and make sure you subscribe to the thread with instant email, it is NOT the default.
 

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thanks for the tip. Actually I just discovered (as in less than a minute ago LOL) that I was getting emails, but for some unknown reason they were going to my spam folder. They didn't used to do that. At any rate I have corrected that problem so I should be fine now. However I am afraid it may have cost me the sale of my Moonroof.
 

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thanks for the tip. Actually I just discovered (as in less than a minute ago LOL) that I was getting emails, but for some unknown reason they were going to my spam folder. They didn't used to do that. At any rate I have corrected that problem so I should be fine now. However I am afraid it may have cost me the sale of my Moonroof.
GM seems to be a patient man. I wouldn't worry.
 

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Yeah, that's right. You have an Explorer.

I regularly swap in car valve body's to those for people to get where you want to be. The transmission internally is identical and the computer doesn't care what you do with the valve body. But yes, the valve body has some differences.

D
 
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