Kickdown band lever ratios

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mopar4x4stroker

mopar4x4stroker

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I understand the higher the ratio, the tighter the band clamps the drum and quicker it shifts. But, why so many different ratios? Is a 5.0 too much for the street? How hard would it shift? Any other input is much welcomed.

Thanks
 
Depending on how fast it applies it may not shift different at all.
The difference is leverage, so if the oil that applies it is slow then it will just hold stronger and not apply harder.
 
^^right^^

There's so many ratios because there are so many different style of vehicles. A trans made for a Chrysler New Yorker will be programmed for a soft cushy shift. A trans. for a RV or heavy service vehicle will be programmed for a real firm shift. Then there's everything in between.

BTW: as far as I know the only time a 5.0 lever was used on a production vehicle was in a Hemi application. It really shouldn't be used in any trans. except the Hemi trans because the Hemi trans had a 1/2 wider front band than all the rest and it needed more leverage to clamp it down. Most of the time a 5.0 lever will cause 2-3 shift overlap in a average 727. I don't even like using 4.2 levers any more cause of overlap problems. When you have a good shift kit there's really never a need for a ratio higher than 3.8 IMO. The only exception to that are aftermarket manual valve bodies that specify using a 4.2 or 5.0 lever
 
I have a 904 with a TF-2 kit and a 3.8 lever. Shifts are fast and firm with no overlap.
 
It used to be that the 5.0 was the way to go. I've one in my slant 6 904 for over ten years now. When I was building my NSS/E 65 Belvedere, Ric at A&A said to use a 4.2 and not a 5.0. I can't remember why . I hope someone chimes in with a answer. The 904 I have now has a 4.2 in it also.All of them had manual valve bodies.
 
Subscribed
I'd like to know the answer also.
Been told many different things.
 
Darter6 said:
It used to be that the 5.0 was the way to go. I've one in my slant 6 904 for over ten years now. When I was building my NSS/E 65 Belvedere, Ric at A&A said to use a 4.2 and not a 5.0. I can't remember why . I hope someone chimes in with a answer. The 904 I have now has a 4.2 in it also.All of them had manual valve bodies.
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longarm said:
Subscribed
I'd like to know the answer also.
Been told many different things.
Click to expand...

I explained why in post #3. Read it and you'll see why :cheers:
 
Got... 4 904 ..racing..all with 5.0 bands.....no problems.....manual valve bodies and tranzact transbrakes...
 
Well I have a manual VB with a 5.0 and I do have overlap. I put in the 5.0 with a stock VB and had overlap. I swapped to the manual VB that recommended a 5.0 and still have overlap. I can't seem to shake it. I should have swapped to a 3.8 when I last had the engine out, but I didn't think about it.
 
fishy68 said:
^^right^^

There's so many ratios because there are so many different style of vehicles. A trans made for a Chrysler New Yorker will be programmed for a soft cushy shift. A trans. for a RV or heavy service vehicle will be programmed for a real firm shift. Then there's everything in between.

BTW: as far as I know the only time a 5.0 lever was used on a production vehicle was in a Hemi application. It really shouldn't be used in any trans. except the Hemi trans because the Hemi trans had a 1/2 wider front band than all the rest and it needed more leverage to clamp it down. Most of the time a 5.0 lever will cause 2-3 shift overlap in a average 727. I don't even like using 4.2 levers any more cause of overlap problems. When you have a good shift kit there's really never a need for a ratio higher than 3.8 IMO. The only exception to that are aftermarket manual valve bodies that specify using a 4.2 or 5.0 lever
Click to expand...

Good to know, Guess I should expect some overlap with a 4.2 installed when I finally get the trans into the car...with the understanding that My only counters being to adjust the front band and the adjusting the restrictor cup size. I don't necessarily mean at the same time.

It's really hard to keep up. lol
 
AlV said:
Guess I should expect some overlap with a 4.2 installed when I finally get the trans into the car...with the understanding that My only counters being to adjust the front band and the adjusting the restrictor cup size. I don't necessarily mean at the same time.

It's really hard to keep up. lol
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Not necessarily. It's all in the combination. As long as you have enough springs in the front clutch, 2 springs (or 1 real strong one) in the front servo, and the front clutch clearance isn't too tight you should be ok. Seen many that were ok, but also seen some that aren't. Hopefully it doesn't overlap because that's real detrimental to a trans. It's really not too hard to change a lever if you do have problems. Just drop the pan and VB and take off the torque converter cover and you can use a 1/4" drive ratchet and extension to take out the plug that leads to the lever pin. Then slide the pin back just far enough to get the lever out and the new one back in. Hopefully you don't have to worry about it
 
Leadfoot said:
Well I have a manual VB with a 5.0 and I do have overlap. I put in the 5.0 with a stock VB and had overlap. I swapped to the manual VB that recommended a 5.0 and still have overlap. I can't seem to shake it. I should have swapped to a 3.8 when I last had the engine out, but I didn't think about it.
Click to expand...

That's rare. Don't usually have problems with a manual valve body. I wonder what spring(s) are on the front servo and how tight the front clutch clearance was? You can change out the lever fairly easy with the trans in place. Just posted above how to do it
 
fishy68 said:
Not necessarily. It's all in the combination. As long as you have enough springs in the front clutch, 2 springs (or 1 real strong one) in the front servo, and the front clutch clearance isn't too tight you should be ok. Seen many that were ok, but also seen some that aren't. Hopefully it doesn't overlap because that's real detrimental to a trans. It's really not too hard to change a lever if you do have problems. Just drop the pan and VB and take off the torque converter cover and you can use a 1/4" drive ratchet and extension to take out the plug that leads to the lever pin. Then slide the pin back just far enough to get the lever out and the new one back in. Hopefully you don't have to worry about it
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Thank you Tracy! btw.. My 340 is almost done.. probably 3 wks out. But I have a long way to go on the body. If all goes well I'll let you know how it runs in July 2014. :D
 
Fishy. I'm not 100% sure that was it. Mostly because in my thinking a 5.0 lever will release the band sooner. I'm going to give that a try anyways. I really don't have anything to lose. I just assumed the converter was in the way. So I never really put any thought into it. If it's not that, I'm pretty well stumped. It's not a real problem as long as I'm going 2-3 under load. When it's not under load I can hear a chirp as the rear tires grab the pavement. Under load it's better but the 2-3 still isn't as crisp as it should be. Sounds like something to do before the Spring thaw.
 
Leadfoot said:
Fishy. I'm not 100% sure that was it. Mostly because in my thinking a 5.0 lever will release the band sooner. I'm going to give that a try anyways. I really don't have anything to lose. I just assumed the converter was in the way. So I never really put any thought into it. If it's not that, I'm pretty well stumped. It's not a real problem as long as I'm going 2-3 under load. When it's not under load I can hear a chirp as the rear tires grab the pavement. Under load it's better but the 2-3 still isn't as crisp as it should be. Sounds like something to do before the Spring thaw.
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The 5 lever releases the band slower actually, since it takes more movement on the servo end for it to move the band.
More leverage on the band means more travel at the servo, and therefore it takes more time to move it.
Just putting a stronger spring in there would probably clear up the overlap.

For the 2-3 shift you can open up the direct clutch apply oil hole in the separator plate to get more volume to the clutch quicker but you need that front band to come off faster also, or you will get the 2-3 bind (overlap) again.

If you put a stronger spring in the servo, open the direct clutch apply hole, and use a lever with less ratio you would get a nice quick and firm 2-3 shift.
This is what I would do if were my trans, and it can all be done without taking the trans out.
 
I'm going to have to differ with you on that one. Not for the sake of argument of course. Simply for the sake of understanding. As you can see as the ratio increases the indent that the interlink sets in gets increasingly closer to the center of the fulcrum. While it will take longer to engage the opposite should happen on the release. Thus the release should occur sooner. Unless I'm just not seeing things right.
transkckdwnlvr1.jpg
 
longarm said:
Subscribed
I'd like to know the answer also.
Been told many different things.
Click to expand...

I know I'm kind of thick, but this is the same stuff
I keep running up against as far as explanations.
Hope it gets hashed out once and for all in this thread
cause I put a 5.0 lever in my 727 and expect it will be fine.
 
The 5.0 lever ain't the devil. It's the best of them all. As long as you run the wider front band like it was designed to be used with, you will be fine. Also, you may even need to run a wider drum to accommodate the band. As long as you run the right stuff, you'll have zero overlap. The Hemi transmissions didn't overlap a damn bit.
 
Leadfoot said:
I'm going to have to differ with you on that one. Not for the sake of argument of course. Simply for the sake of understanding. As you can see as the ratio increases the indent that the interlink sets in gets increasingly closer to the center of the fulcrum. While it will take longer to engage the opposite should happen on the release. Thus the release should occur sooner. Unless I'm just not seeing things right.
Click to expand...

Greg's actually right. Yrs. ago when I first looked at them I thought the same as you that the 5.0 lever would apply and release faster but it doesn't. Just as the driveshaft on a vehicle with 4:10 gears has to move farther (more revolutions) than a car with 3:23 gears, the higher ratio lever causes the servo to have to move farther to apply the band. If you notice the recommended adjustment for the 5.0 lever is 2 turns, where-as the adjustment for a 3.8 lever is more. The servo only has so much stroke length so their making up for it by having you adjust the band tighter.
 
RustyRatRod said:
The 5.0 lever ain't the devil. It's the best of them all. As long as you run the wider front band like it was designed to be used with, you will be fine. Also, you may even need to run a wider drum to accommodate the band. As long as you run the right stuff, you'll have zero overlap. The Hemi transmissions didn't overlap a damn bit.
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Never said it was Rob. If you read my earlier description you'll see that I said it was designed for use with the wider band/drum. That band and drum are hard to find and real expensive so very few guys run them. With today's improved band materials the wider band isn't a necessity like it used to be.
 
RustyRatRod said:
The 5.0 lever ain't the devil. It's the best of them all. As long as you run the wider front band like it was designed to be used with, you will be fine. Also, you may even need to run a wider drum to accommodate the band. As long as you run the right stuff, you'll have zero overlap. The Hemi transmissions didn't overlap a damn bit.
Click to expand...

Totally agree Rusty
All the right parts working together is always best.



fishy68 said:
Greg's actually right. Yrs. ago when I first looked at them I thought the same as you that the 5.0 lever would apply and release faster but it doesn't. Just as the driveshaft on a vehicle with 4:10 gears has to move farther (more revolutions) than a car with 3:23 gears, the higher ratio lever causes the servo to have to move farther to apply the band. If you notice the recommended adjustment for the 5.0 lever is 2 turns, where-as the adjustment for a 3.8 lever is more. The servo only has so much stroke length so their making up for it by having you adjust the band tighter.
Click to expand...

The only way I could think of to explain it was to say that the strut would have the same ratio whether being applied, or released.:D
 
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