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68 Sedan

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Ok...One thing I discovered while driving "IT" was it was shifting a bit quick, by that I mean at low speeds. It has a cable instead of linkage so I figure, no prob, check the slack.

So I checked and it seemed a bit much. So I make an adjustment. Now it's a bit to tight, as it's delaying the 2-3 shift (under mild acceleration) until I lift on the pedal.


Well, under WOT I expected to old a gear for quite some time. But it doesn't. Motor gets to about 4500 rpm and then the trans shifts. You would think that if it's holding in gear till I lift during mild acceleration it should hold when pegged.

So what's the deal? Why is it shifting at 4500? I can't tighten the cable any more and expect it to shift. As is, I need to loosen it back up a bit.

So what's the problem?
 
The governor is set to shift at a pre-determined rpm no matter how tight you have the throttle pressure cable set. Adjusting the throttle valve does increase or decrease low speed shift points but at WOT doesn't have much affect. There are 3 ways to get it to shift higher.

1- replace the weight/spring package in the governor. They are available from Mopar perf. This is the best way to do it IMHO

2- In the valve body there are the 1-2 and 2-3 shift valves that are controlled by spring pressure and work in conjunction with the governor. If you get real lucky you can find some that will make it shift higher but it's kind of a crap shoot to get them even. In other words you may get the 1-2 wide open shifting at 5500 but the 2-3 may only shift at 5000 or possibely 6000. If it's shifting evenly now, in other words at 4500 into 2nd and 4500 into 3rd I'd leave these springs alone and do the governor package swap. I usually only mess with the 1-2 and 2-3 springs when they don't shift evenly. Hope that makes sense.

3- increasing the line pressure raises the shift points somewhat but you have to be careful not to go too high or it'll start popping seals or won't shift at all. This is also a guessing game as to how much to raise it because you can't do it externally. The adjustment is on the side of the valve body inside of the pan. It does have one more advantage that it firms up the shifts somewhat.
 
I'm very curious about this cause I ordered a 6000 (aprox) governer weight for my A518 from A/A and it still full throttle shifts about 4500. I was told it should work the same as the 727.
 
mguner said:
The Gill Younger kits say to adjust line pressure to accomodate the thickness of a pan bolt (5/16) them two more turns with the allen wrench. This kit with the new manual valve does wonders....

http://www.transmissionpartsusa.com/A904_A727_TF6_TF8_valve_body_calibration_kit_p/500-00054930a.htm
Click to expand...

They may say to adjust the line pressure 2 turns but that's when all the other parts from the kit is used. What happens if you don't use the other parts and just do one part of a modification. It may work right, it may not. It's a crap shoot that may have dire consequences. I have used the Trans-go manual valve kit and it does correct some inherent problems of torqueflites as are mentioned in the add for the kit but none of them were mentioned by Sedan. He just said his wouldn't go higher than 4500 before it shifts. Also the Trans-go kits I've put in don't affect shift rpm much at all. They just improve on the performance of the trans.
 
charger70 said:
I'm very curious about this cause I ordered a 6000 (aprox) governer weight for my A518 from A/A and it still full throttle shifts about 4500. I was told it should work the same as the 727.
Click to expand...

What year is your 518? If it's an earlier one (before 96 I believe) it should have worked. If it's a later one they're computer controlled. I haven't been in a 518 valve body enough to know what differences their are from a 727 so other than what I've mentioned about the year diff. I don't know. You might call Rick at A&A and see what he says.
 
One of the problems in the kit instructions mentioned is early shifts from spring fatigue or heat soak etc.... but yes the kit also includes a new converter valve spring and cold bypass spring. I combine this kit with a couple of mods from the tf-2 instructions of drilling out some holes in the seperator plate, removing a check ball and channel wall and blocking the accumulator.
 
mguner said:
One of the problems in the kit instructions mentioned is early shifts from spring fatigue or heat soak etc.... but yes the kit also includes a new converter valve spring and cold bypass spring. I combine this kit with a couple of mods from the tf-2 instructions of drilling out some holes in the seperator plate, removing a check ball and channel wall and blocking the accumulator.
Click to expand...

I see what your saying that they may advertise it raises the shift points so on that point I stand corrected. That may be true in a very few trans but the ones I've installed don't make much over 100 rpm difference and in some cases don't make a diff at all. I usually just do the TF-2 kit cause it comes with more than just the little kit and notes on drilling the seperator plate. I really doubt either kit would help allot though cause it's allready shifting at 4500. That's pretty much where they all shifted at stock. Allot of them shifted in the upper 3000 range so his is actually doing pretty good. A kit may up it a little due to increased line pressure but I doubt it'll go much over a couple hundred rpm's higher. Another concern is how old is this transmission? If it's original I wouldn't even think of installing a kit or upping the line pressure cause you take a chance of blowing seals.
 
Mine is a 93 w/Lockup.
I don't know if it was on A-bodies but I recall reading a few months ago another guy with the same low shift pt question-unresolved that I know of.
I'm starting to wonder if it could be a valve body issue. I thought of swapping the one out of my 69 BEE but don't think I can because of the L/U.
 
charger70 said:
Mine is a 93 w/Lockup.
I don't know if it was on A-bodies but I recall reading a few months ago another guy with the same low shift pt question-unresolved that I know of.
I'm starting to wonder if it could be a valve body issue. I thought of swapping the one out of my 69 BEE but don't think I can because of the L/U.
Click to expand...

Have you tried adjusting the throttle valve cable? I had a 93 Dakota with a 518 and the cable had the ability of being adjusted farther but the cheesy cable adjuster/retainer wouldn't hold it tight enough and every time I'd adjust it for max travel at WOT when I pressed the accerator all the way down the cable would slip back in. I finally adjusted it where I wanted it and put a real small hose clamp on the cable so it couldn't slip into the adjuster/retainer and it worked fine. With the stock governor weights it shifted at 48-4900 then. Before it would only go to 41-4200 when it shifted.

You can't use a 727 VB also because it has no lower half that controls the o.d.
 
This may be a dumb question. Have you checked the kickdown linkage/cable? If improperly adjusted, the tranny runs to high gear as soon as it can.
 
Thanks for the advice. I know nothing about this trans other than what the P.O. told me. He claimed it was store bought from Mancini, but I haven't seen any marking that would verify that....IF they mark them. So I'm guessing it isn't set up properly.

But I'm lucky in one respect. Phoenix Transmissions (of One Lap fame) are in my neck of the woods. I've had a few trannies built by them before, and they really know their stuff. You tell them what stall you want (they build convertors in house) and how/where you want it to shift, and that's what you get. So since it looks like the front pump seal is leaking (you've seen the mess underneath) I guess I'll just take it to Phoenix and let them fix it.

Thanks again
 
68, if they fixit for ya, will you let me know what they say about the cause for the low shiftpoint?

By the way mine has the 3 piece mechanical linkage and is on the stop at full throttle. Actually puts a little tension on the rods at full throttle.
 
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