Whats the "j-mod" for 4r70w?

[fastangboi]

ive read about it and heard of a few guys that regret it. but some say they wish they did it instead of getting a shift kit.

does any one know where a write up is?

has anyone had any personal experience with it?

 

[fastangboi]

i cant find it on the TCCOA site, even though countless amount of guys are told to go there.

 

[triggz]

The information is under the tech articles:
http://www.tccoa.com/articles/tranny/index.html#

If you're not an experienced transmission tech, it will be very confusing.

In 99+ transmissions the jmod is removing the 1-2 and 2-3 accumulator springs, and drilling out a few holes on the seperator plate.

I have had it done to mine (along with a cooler and 4.10s) for about 2-3 years and 40-50k on it with no problems. It shifts firm, crisp and quick as possible.

 

[TGJ]

ive read about it and heard of a few guys that regret it. but some say they wish they did it instead of getting a shift kit.

does any one know where a write up is?

has anyone had any personal experience with it?

The J-Mod is the only shift kit to go with when you have a 4R70W. The others will cause your transmission to fail, it is a question of when not if.

 

[fastangboi]

The information is under the tech articles:
http://www.tccoa.com/articles/tranny/index.html#

If you're not an experienced transmission tech, it will be very confusing.

In 99+ transmissions the jmod is removing the 1-2 and 2-3 accumulator springs, and drilling out a few holes on the seperator plate.

I have had it done to mine (along with a cooler and 4.10s) for about 2-3 years and 40-50k on it with no problems. It shifts firm, crisp and quick as possible.

thats what most shift kits do anyway right. i know of a few you have to put a rivet in a certain spot too.

i wonder if its too harsh of a shift for a DD

 

[san~man]

You don't put in any "rivets" nor is it too firm for a DD.

I use/drive my car everyday and in fact, during part throttle shifts, it shifts softer than stock. WOT shifts are a different story though

 

[fastangboi]

does the J-mod get rid of that 2-3 studder while cruising w/ OD off?

 

[triggz]

does the J-mod get rid of that 2-3 studder while cruising w/ OD off?

That 'studder' you feel is probably your TC locking up. At WOT, in OD, and low cruising speeds the torque converter locks at a 1:1 ratio for optimum power transfer. Just like fully engaging a clutch.

If anything, it makes it more noticable. But you will feel the trans 'drop' into gear very firmly, the car doesnt fall back for a moment while it shifts anymore.

 

[fastangboi]

it seems to happen more at 40-45mph, and ive heard its an electrical problem in the 4r70w.

 

[2001sleeper]

just get a new valvebody. They are real easy to install.

 

[fastangboi]

just get a new valvebody. They are real easy to install.

isnt that the whole big 1/2 inch thick plate that the stuff is wired to?

 

[2001sleeper]

ya, sort of looks like a crazy large computer chip sort of.

 

[VicRattlehead]

just get a new valvebody. They are real easy to install.

why? what do you recommend?

 

[Jakes]

isnt that the whole big 1/2 inch thick plate that the stuff is wired to?

You really need to read the whole section on the 4r70w transmission at http://www.tccoa.com./articles/tranny/index.html# especially the "Transmission 101" part.

 

[2001sleeper]

why? what do you recommend?

My lentech unit works well. They build it to your specs and don't just pull something off the shelf like others do. I am happy with my unit. Been running it for almost a year now.

 

[san~man]

My lentech unit works well. They build it to your specs and don't just pull something off the shelf like others do. I am happy with my unit. Been running it for almost a year now.

I'll take my Jmod valve body over the Lentech any day. JMO of course, but Jerry DID design the freggin trans to begin with.

Jmod, trans cooler, stall and gears. Fun party

 

[triggz]

Would anybody be interested in making a video comparing jmod vs stock? If someone here has similar mods to mine but no jmod, we can make some identical clips. Would need to have 4.10s and o/r midpipe for best comparison..

 

[sgarlic]

Great idea.

 

[2001sleeper]

I'll take my Jmod valve body over the Lentech any day. JMO of course, but Jerry DID design the freggin trans to begin with.

Jmod, trans cooler, stall and gears. Fun party

have you owned lentech products and used them, or are you just making a comment?
I've seen failed transmission due to improper J-mod modifications.

 

[triggz]

have you owned lentech products and used them, or are you just making a comment?

Lentech makes great products, but thats a lot of unnecessary spending for a street car that doesnt need a whole new valve body where the stock one works fine. Thats like saying he should get a new forged dss shortblock just because its better.

I've seen failed transmission due to improper J-mod modifications.

I've seen engines failed due to improper oil changes. Stop changing your oil!