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Discussion Starter · #1 ·
I have a pretty loose convertor in my truck.
when towing heavy if i have to drop down into second on a nasty grade it kinda sucks because i loose tc lock-up and i can watch the tranny gauge start climbing.

Im wondering if theres a way i can modify something and get it to do a forced 2nd gear lock-up.

The trans is a 47re, I have a lockup switch, and the valvebody has a transgo shift kit in it.:thumbsup:
 

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They are talking about a lock up switch.. it locks it whatever gear you want and stay locked until you flip the switch off. It is controlled by a wire on the pcm.. right? I need to do it. Just unlock it when you start to slow down and dont lock it during shifts if yiu have stock shafts
 

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They are talking about a lock up switch.. it locks it whatever gear you want and stay locked until you flip the switch off. It is controlled by a wire on the pcm.. right? I need to do it. Just unlock it when you start to slow down and dont lock it during shifts if yiu have stock shafts
Not quite, it allows you to do so after the Valve Body has been modified. A stock VB will not lock in manual 2nd or 1st, they will not lock in 1st gear while in D either, nor will they allow a 4-3 locked downshift.

Some JB weld placed here will get you 2nd lockup


Here is a better overview of where you will be placing it.


This shows the passage through the separator plate that you are ultimately blocking.


I nor any of my customers have needed 1st gear lockup, and with it's tendency to be rather brutal to even billet input shafts I have no desire to do the VB mods to get it.

The 4-3 locked downshift is pretty simple you just flip the converter timing valve and spring around in their bore. This core VB has been robbed of a few parts so it's not visible, but in the first picture you can see to the right of where the JB weld is to be replaced is a pair of valves. The one on the far right is the converter timing valve. I will try to get a picture posted later for clarification.
 

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:doh: i didnt know they wouldnt lock up in second or first. :confused013:
my bad..
thanks for the knowledge :thumbsup:
 

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So with the 47re in my 99, will a little jb weld in that passage grant me the key to a locked converter in manual second?


Sent from my iPhone using Tapatalk
 

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Not a problem gentlemen, let me know if you have any questions.

So with the 47re in my 99, will a little jb weld in that passage grant me the key to a locked converter in manual second?


Sent from my iPhone using Tapatalk
Yes, any four speed torqueflight transmission will respond to this modification by locking up in 2nd manual.
 

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Not quite, it allows you to do so after the Valve Body has been modified. A stock VB will not lock in manual 2nd or 1st, they will not lock in 1st gear while in D either, nor will they allow a 4-3 locked downshift.

Some JB weld placed here will get you 2nd lockup


Here is a better overview of where you will be placing it.


This shows the passage through the separator plate that you are ultimately blocking.


I nor any of my customers have needed 1st gear lockup, and with it's tendency to be rather brutal to even billet input shafts I have no desire to do the VB mods to get it.

The 4-3 locked downshift is pretty simple you just flip the converter timing valve and spring around in their bore. This core VB has been robbed of a few parts so it's not visible, but in the first picture you can see to the right of where the JB weld is to be replaced is a pair of valves. The one on the far right is the converter timing valve. I will try to get a picture posted later for clarification.
So If I had 2nd gear lock up for a while and lost it randomly could the Plug that the builder put in have fallen out? very good info you just saved me a trip to the trans shop. I assme it needs to be block off the entire port to the spacer plate?
 

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So If I had 2nd gear lock up for a while and lost it randomly could the Plug that the builder put in have fallen out? very good info you just saved me a trip to the trans shop. I assme it needs to be block off the entire port to the spacer plate?
I suppose that is possible, I've never had a plug fall out, but I use a good deal of JB weld and rough things up in the passage with a mini carbide. The pic Spence posted on CompD is a pretty good illustration.
 

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I have a really stupid question... What is to low of rpms in 2nd to throw it in lock up? The other night i was cruising in second and flipped the switch at about 1300rpms and the whole truck started shaking and I could hear what I'm assuming was the clutches in the converter clattering around and then snapped my parking rod.
 

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I have a really stupid question... What is to low of rpms in 2nd to throw it in lock up? The other night i was cruising in second and flipped the switch at about 1300rpms and the whole truck started shaking and I could hear what I'm assuming was the clutches in the converter clattering around and then snapped my parking rod.
I'm trying to figure out how that would even happen to the park rod... but you may have been to low, I've had them buck pretty hard if there's a decent load and they fall below 1200rpm on a shift.
 

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Pretty sure I was in second, was only going about 15-20mph. Not sure how it broke the parking rod either I drove it around to make sure everything was okay and when I threw it into reverse to turn around it wouldn't go any further down than neutral when I went to throw it back in drive.
 
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