727 Shifting from 2nd to 3rd is sloppy, what could it be?

[idrivemopar]

So, the more I drive my car since its been restored, only 600 miles on rebuilt trans, but I have noticed the shift between 2nd and 3rd is hesitant, almost feels like its trying to go into 3rd before 2nd is disengaged or maybe even getting a bit neutral before the shift to 3rd. This happens when I am driving the car normally (Not getting on the gas, but slowly accelerating) in Drive, and there is a bit of a clunk when the shift occurs. Also, when under full power, pedal to the metal, I can feel it as well although not as pronounced.

I have checked linkage and it seems to be spot on with the shifter position and being in the correct gear, same for kick-down linkage.

Is this a problem with the 2-3 shift valve or maybe a weak valve spring?

Any thoughts? I hate to have to pull this thing out again.

 

[67 coronet]

check the normal stuff first.trans mount,ujoints,and u bolts tight on diff.new bolts will get loose if all new parts used,and need a good retighten.pinion angle good?if all that is good,then look into trans.

 

[miller]

Possible the problem (bit of a clunk?) in the shift body, maybe something hanging up. You need to look in the service manual, under trans, trouble shooting for the 2-3 shift. That will give you a list of possibles to check.

 

[383man]

Does it almost feel as it you step on the brakes a little before it shifts ? If it does it sounds like shift overlap. Meaning the front clutch (comes on in third) come's on before the front band fully release's. Seen it many times if it is that. First check the front (kickdown band) band adjustment and make sure its not to tight and you can set it a little to the looser side and see if that helps any. If its real bad many times you have to go in the trans and install a restricter to slow the front clutch down a tad. Or it may not have the right amount of springs (not enough) in the front clutch unit but you would have to pull the trans apart to check that. I found on cars that have the 2-3 shift overlap that if you lift on the gas pedal as it shifts into third it hits a lot less harder. Or if you have it floored like when racing then you also dont notice it. But if you drive it normal and keep your foot about 1/4 to halfway down like normal driving then you feel it the most. If it is overlap meaning two friction units being on at the same time and it does it real bad then I would want to fix it. If it only does it a little you can usually drive it so it wont do it very hard. Ron

 

[idrivemopar]

Hey 383man, you described it much better than I did, and that's exactly what's happening and how it feels. So, are you talking about the kick down lever or the front band itself?

 

[idrivemopar]

Wait! LOL, I see what you are referring to in my service manual, I will look into that.

 

[383man]

Good luck and let us know how you make out ? Ron

 

[idrivemopar]

Hey 383man, Well, I adjusted my kick down lever, my shift speeds from 1st to 2nd and 2nd to 3rd were too low, that is much better improvement, however, the lurch from second to 3rd is still there, although not as pronounced. Talked to my trans shop, and he said it was a kick down lever issue, not the kick down band, so, I guess I will have to take him for a ride to see if he still feels its not the band that needs adjusting. Even with heavy duty parts inside, I still think it should shift soother.

 

[Yatzee]

You have the infamous shift overlap. I had two that did this and the only resolution I found was to install a B&M shift kit (3 in 1) but I used only the heavy duty option. The shifts are now clean and fast with no overlap. I give this kit five out of five stars!

 

[idrivemopar]

Hey Yatzee, its interesting you mention B&M, because the trans was a B&M trans before I had it rebuilt, done locally, and I asked they guy if what he was doing was the same, and he said yes, and installed all heavy duty parts. So now im still wondering what to do next except take the trans shop guy for a ride and see what he thinks.

 

[62 Dart Convertible]

If I had paid a trans shop to rebuild it, I would not touch it without him looking at it first. Let him "own" the problem.

 

[Yatzee]

If it truly was a B&M trans, B&M would have addressed this issue at the time of assembly so I smell a skunk in the chicken shed.In the process of rebuilding, the shop you had do it most definitely would have to clean the shifter body as part of the rebuild. Now if it was his practice (to save time) to install an already cleaned body off the shelf you're back to square one. If you can manage to get the instructions online from B&M's site (which you can)you will see the mods and methods for altering the shifter body. Their very straight forward and easy to do. Discounting the fact that he replaced and adjusted the bands properly then the only item left to cause this overlap issue is the shifter body. You may be between a rock and a hard place if he denies responsibility so you may have to remove the shifter body yourself to confirm these mods have been done. As stated earlier perhaps there's nothing wrong with the tranny rather the pressure control linkage is adjustment is wrong. I know that the original mechanical linkage of rods and swivels had a specific method for adjustment found only in Mopar manuals and if you use cable there's a specific method as well. If you pull on the pressure lever at the tranny too soon the higher pressure causes (bang) shifts and if the lever moves too little the lack of pressure has the same type of result except poor band engagement may result in a loss of gear shifts and serious glazing of the bands surface. I had an instance one time where the c-clip ring for the front servo popped out allowing the piston to drop resulting in the loss of second. Go see the shop and have them explain just exactly what they did and didn't do and don't take any BS. You paid good cash to have the work done by people who claimed to know what their doing so make them take ownership for their work at no additional expense to you.

 

[idrivemopar]

Wait, hold on a second, I'm not blaming my shop for anything, they did nice work, and the guy has a good rep and stands behind his work.

A bit more information on my original trans. The tail shaft blew out in the 80's, back when I was a kid, so the whole thing was replaced, didn't know any better back then, so the trans I have now, has always been a mystery, because the housing was labeled as a B&M street strip trans, and the housing is from 69. I was never certain that it had the kit installed to begin with, because who knows what guts were in it when it was installed back in the 80's. I've already talked to my guy that did the rebuild, and this was well over a year ago, and he cant remember if it had the kit or not, and if it didn't, no biggie, and he did use the original valve body, nothing new was added there. I am going to first check the kick down band adjustment, just to see where it is, if it is correct, then next step will be to install a shift kit if it really doesn't or never had one. I'm just trying to get everything dialed in on my car. That is all.

 

[bigmanjbmopar]

Not sure if this helps you or not, it really pertains to my situation where I had new TTI headers and the linkage had to be re adjusted after being cut, but the method of adjustment is here and I added some notes for myself and what I did to get it where it needed to be. Hope it helps you.







Without the mark ups

 

[idrivemopar]

Thanks Bigmanjbmopar, I have already made the modifications for the TTI headers, and that all is good, its a bit easier since I have console shifter.

I adjusted my kick down band a bit this afternoon, feels better, I may need another quarter turn out, on the adjustment, it was too tight, only 1.5 turns out, and now about 2.25 out, so hopefully when it all cools down later, I can make another slight adjustment. Its a pain, because I have to drop the header on that side to get a clear shot at the adjustment, since I also have custom cooling lines installed as well, darn headers! LOL If that doesn't totally cure it, than I will start looking at verifying if I do or don't have a shift kit in the beast.

 

[idrivemopar]

Looks like its shift kit time. At full adjustment on the kick down band, 2.5 out, still getting a little slop from 2nd to 3rd.

 

[Edwards]

Hello this is Eddie from San Antonio,
I know this is an old thread but I'm going through this exact same problem on my transmission in my charger. Im curious what ended up being the solution to your transmission shifting? Thanks for your response.
-Eddie

 

[wyrmrider]

Eddie
Buy a transgo reprogramming kit
call the tech line and they will advise you ask for Dave or Jim
as the thread shows it could be several things
wrong number of springs, wrong lever (ratio), not enough clutch clearance, bad band adjustment
you can start by setting the throttle rod correctly and dbl checking the band adjustment
transgo has their own way of adjusting the bands- they may have you try it

 

[Edwards]

I will try that. I do have the transgo kit installed. Hopefully it is an adjustment that doesn’t require removing the transmission again.
Thanks.

Eddie
Buy a transgo reprogramming kit
call the tech line and they will advise you ask for Dave or Jim
as the thread shows it could be several things
wrong number of springs, wrong lever (ratio), not enough clutch clearance, bad band adjustment
you can start by setting the throttle rod correctly and dbl checking the band adjustment
transgo has their own way of adjusting the bands- they may have you try it

 

[lewtot184]

Does it almost feel as it you step on the brakes a little before it shifts ? If it does it sounds like shift overlap. Meaning the front clutch (comes on in third) come's on before the front band fully release's. Seen it many times if it is that. First check the front (kickdown band) band adjustment and make sure its not to tight and you can set it a little to the looser side and see if that helps any. If its real bad many times you have to go in the trans and install a restricter to slow the front clutch down a tad. Or it may not have the right amount of springs (not enough) in the front clutch unit but you would have to pull the trans apart to check that. I found on cars that have the 2-3 shift overlap that if you lift on the gas pedal as it shifts into third it hits a lot less harder. Or if you have it floored like when racing then you also dont notice it. But if you drive it normal and keep your foot about 1/4 to halfway down like normal driving then you feel it the most. If it is overlap meaning two friction units being on at the same time and it does it real bad then I would want to fix it. If it only does it a little you can usually drive it so it wont do it very hard. Ron

I agree with this. sometimes kick down linkage adjustment (too aggressive) can make the problem worse. I have a TF2 kit in one of my torqueflites and low speed overlap is bad. backing off the kick down adjustment helps mine.