The 2-3 bindup shift by DTT:<br><br>http://www.dieseltrans.com/phpBB/viewtopic.php?t=212

 

Interesting article...<br><br><br>Tony

 

Interesting how they put up an article like that and lock it so that nobody can reply to it. :

 

To their credit, I think all their regular articles are locked to avoid huge threads in that section, but then you can probably discuss them down in the other part of the forum. I'm not sure, but that's what I get out of it.

 

They didn't start doing that until after the emjay/bind up shift thing happened.

 

Jack in addition to what you said , Bill has transmission builders and just everyday guys world wide that read the site and use it as a resource. At their request and many that do not want to see the back and forth discussions we have seperated the two and as you stated the discussion forum is available to those that want to comment further.

Stakeman,

I cannot tell you how many requests we had to get rid of your ATS buddy Edward, more after the emjay post than usualy but as we did not censor him as tempted as Shanti was, the very least we could do was accomodate those that do not want to read his posts.

 

This bindup shift must go unnoticed cause I can't feel when the tranny is binding up at all in mine.

 

BB: This stuff Bill K says sounds logical to me. Even if you do not feel the bindup I believe ( please note that this is my opinion) that if 2 gears are applied the same time one of the clutches must slip. Even if it does just drag with lets say 5 horsepowers ( something you won't feel in a RAM ) I imagine having a 5HP grinder working away in the tranny. <br>And if you read the article it says something about the tolerances. If you are on the right specs maybe there even is no bindup because you were lucky with the guy assembling your stock unit. <br>I do assume that with stock tolerances that big there is some explanation why there are such different experiences with stock trannies and bombing. <br><br>Just my 2c, and please don't make another flaming war out of this. PM-me if you disagree with my opinion. <br><br>AlpineRAM

 

Since we're trying to learn more about bindup and what causes it, there was a post a while back by Bill K that stated the following:

[red]&quot;Band adjustments especially the front band are critical because of the Dodge shift pattern. A dodge trans shifts 1-2, back to 1st then into 3rd. If the 2nd band does not release before the third gear clutches come on, you will have a bind up which will shorten the life of the transmission. I usually go a little looser than factory specs on this front band. Depending on the circumstances i have backed off the band
up to 2 1/2 turns.
Bill K &quot;[/red]

How does this relate to the governor circuit, and how do both of these things affect bindup? Do the governor AND the 2nd band cause this, or can either one cause this problem?

 

If what he is saying is true about the shift pattern. Going from 1-2, then back to 1 and then into 3, wouldn't you notice the engine revving up for a split second when it went from 2 to 1 and then to 3? None the less, it is a messed up shift pattern. I'm not doubting Bill's information, I'm just curious.

 

[quote author=Jack Thorpe link=board=7;threadid=9621;start=0#92349 date=1042646929]<br>How does this relate to the governor circuit, and how do both of these things affect bindup? Do the governor AND the 2nd band cause this, or can either one cause this problem?<br><br>[/quote]<br>As I read it the governor pressure is crucial to the movement of the shift valve. And if the shift valve gets too slow it can cause this bindup. <br>I'll quote Bill K ( last part of the message)<br><br> When you are dealing with a throttle valve and the governor circuit you are now dealing with time. The time it takes to complete the shift is dependent on the amount of throttle pressure or governor pressure. Pascal’s law governs all this.<br><br>When guys start messing around with throttle pressure or governor pressure variation of even 2 or 3 psi in the wrong direction it can cause the shift valve to momentarily stop its motion dramatically shortening the life of the transmission.<br><br>The mass of these Dodge Diesels prevents the average consumer from feeling this bind up. That is why pressure testing and proper diagnostic proceedures is imperative . <br><br>End of quote<br><br>As I see it the shift from 2 to 3 is done by applying the clutch and releasing the band the same time. If you just release the band you are in first gear, if you apply the clutch and still have the band applied you have a bindup. So therefore I think that if you adjust the play on the band a little looser you will release the band earlier and therefore the band adjustment can play some role. And since the clutch is applied by the same oil that releases the band the relation between the volumes of the servo and behind the piston of the clutch will play some role and the bores where the oil goes to the pistons and clutches also <br><br>So these are my 2c worth of OPINION. Please correct me if I did get something wrong. <br><br>AlpineRAM

 

How would 2 - 3 bind up improve drivability?<br><br>Alpine,<br>It sounds like you are saying that the tranny would have to be out of adjustment for it to happen?

 

Stakeman,

I cant adquately discuss all the details simply because i dont know them all. That is Bill's area of expertise. I have learned a lot more as we were doing dealer training during the Christmas - newyears Break.

While Black Mountain Diesel was up here training Briar Hopper actually showed me the answer to your question in the Chrysler service manual. As i have a 2000 Dodge this is where it is located . For those of you with different years you look in OPERATION SECTION the kickdown (front) servo portion,
in my manual its on page 21-351.

I did not type the entire thing but here is the section that applies &quot; Otherwise engine runaway or a shift hesitation will occur. To accomplish this, the band retains its holding capacity until the front clutch is applied, giving a small amount of overlap between them. &quot;

I know Bill will be addressing a few of these type questions on his site in the next day or so.

Stakeman,

We did carry the post over to the discussion forum as well so it is accessable if guys have more questions for Bill.

Stefan Kondolay
Diesel Transmission Technology ( DTT )

 

Stakeman: First off I'd like to say that all this is just plain old me thinking and spewing out my thought to get enlightened by the comments of people knowing more than me. <br>Since I do own a 98.5 I don't know for the others. But taking the tolerances that are in the repair manual I can assume that the volume needed for applying the clutch will differ greatly due to the tolerance there. So I did compare it to my espresso machine when I place 2 cups under it. Theoretically these cups should fill simultaneously. But if I take 2 cups of different sizes the larger one will reach the full mark later. So if I take a tolerance into account I must multiply the length in this tolerance with the area of the piston and get the volume tolerance. So therefore I think that this will influence the timing when the clutch is actually applied in relation to the time when the band is actually released. <br>I think that these tolerances were chosen with the stock tranny and engine, and with the costs of a given rate of failures versus production costs etc in mind. <br>I think that there will be a tolerance of how much bindup will actually occur at this shift because this is influenced by lots of factors. So maybe even with a tranny adjusted to factory specs this will occur. ( More or less grave) <br>I believe that the bindup (in a very slight form) was intended by the designers to help the driveability in the following way: Given the tolerances you have to decide whether you have a little bindup due to the servo releasing a tad slower than applying the front clutch or to have a stumble to first gear when the servo releases a tad faster than the front clutch applies. <br><br>As BB said you would notice the engine revving up if it wasn't for the bindup that prevented that. I took the image from a DC service manual. <br><br>As you see the 2-3 shift is the only shift where the tranny has to release one thing and apply the other at the same time. All other shifts are simply applying or releasing one item. <br><br>I am at least as interested in learning everything possible about htese trannies as anybody else. <br><br>AlpineRAM<br>

 

2-3 bind occurs becase of to much over lap during upshift<br>if you were shifting onto a roller clutch or a sprag there would be no bind just the front of the hood rising on upshift. But if the band comes of slow due to leak or band release hole tampered with then the result is a tie up or bind on upshiftSome times the band to tight or even the direct clutch clearence tightened up will do this. There are many varibles but you get the idea here. later