Improving Transmission Shifting
- Thread starter Tools R Us
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
A previous poster mentioned that a similar effect could be reached with the A442F by modifying the primary regulator valve. Could also work on the A440F as well. Would like to investigate further. Anybody have experience with this?
1973Guppie
Supporting Vendor
so what would happen if one has the transgo kit installed and decided to do this as well? I can't remember if replacing a spring on the plunger you pictured was part of my transgo kit or not? Just curious what the effects would be if I were to dial that plunger up to 3 and adjust the kickdown and tranny cables?
I have a question. How does this mod differ from just adjusting the tranny cable on the throttle body? the TB cable adjusts tranny pressure according to engine load so tightening it up should solve the problem. Then what is this valve body sleeve/plunger mod for? What are the differences and benefits?
murf
Lifer
You would have to try it and see, another CSC guy installed the Aussy trans valve body which changes it to 4 settings and it changed the dynamics of the shifting so much we had to put it down to the #1 pressure setting and back off the shift cable due to it "hitting" so very hard. Trial and error after the transgo kit and see since it will change the base line? Im not familiar with it.
Tools describes it in more detail in the first post but while the cable adjustment will change your shift points the plunger mod takes away the flare/slip between gears. Whether the cable is adjusted up or down, it makes the trans shift quickly between gears. Slip/Fare creates excessive heat too so another benefit is less heat generated in the trans and sportier shifts. With the SC and accelerating hard, it would bother me when the l o n g flare between 2nd and 3rd would happen sometimes and seem like losing something when it would happen.
Murf, what are the dimensions of the washer used?
I have an extra washer at the shop I picked up, wing by if you want it.
BTW, we did have to ever so slightly enlarge the center of the washer to comfortably slide over the plunger shaft.
Thanks Murf for the info but I've heard that on the A343 the shift points are controlled by the ECU and the tranny cable is supposed to deal with line pressure whatever that means 
So this is why I am puzzled. So I understand (correct me if I am wrong) that ECU deals with shift points and controls the three solenoids (two gear solenoids and one for lockup), the cable controls pressure (whatever pressure it is) and the plunger mod controls... (????)
So this is why I am puzzled. So I understand (correct me if I am wrong) that ECU deals with shift points and controls the three solenoids (two gear solenoids and one for lockup), the cable controls pressure (whatever pressure it is) and the plunger mod controls... (????)The cable does control pressure based on throttle position. The mod increases pressure across the board by a set amount. I.e. if the normal range of pressure from idle to WOT is (BS numbers) 20psi-80psi, clicking the plunger forward adds (again, BS) 30psi to the entire range, so you end up with 50psi-110psi.
That's not official, just an example of how I understand it.
This adjustment interests me. My truck is nearly stock. 33's and no weight. Crisper shifting would be an improvement for what I do with it.
Would using the second position be a Goldilocks adjustment or is this a try it and see exercise?
Thanks
Dan
Would using the second position be a Goldilocks adjustment or is this a try it and see exercise?
Thanks
Dan
1973Guppie
Supporting Vendor
I adjusted my transmission cable last night, according to the fsm it was out of spec where the stopper sits. My stopper was inside the little rubber boot when it should be up to 1mm outside of the boot. Will be interesting to see if the minor adjustment changes anything next time I drive it.
Murf, what are the dimensions of the washer used?
I have Murf pick me up an extra washer....
OD .734"
Thickness .076"
So in summary, would it be best to do the washer mod on the valve body then tune with the cable setting? Since they both do the same it seems best to max out the VB since that isn't easy to get to but the cable linkage has a decent adjustment range.
Post #67
Last edited:
I just flushed the trans, dropped the leaky pan, turned the plunger to the max (decided not to do the washer mod, wanted to stay conservative on a 212k trans), and changed out the filter. Refilled with full syn ATF. Adjusted the cable a couple turns. The difference is night and day! Wish I would have done this when I lifted my truck. Its a joy to drive again. "jumps" off the line now, rather then just slowly gaining speed before. Would recommend this to anyone with larger tires! do it!
1973Guppie
Supporting Vendor
ok, so an update here, I drove the truck today, and what a difference. Since the SC install it just did not feel "right". It was hitting hard on shifts and the tranny was just acting funny. Felt like it was shifting at the wrong times, too late, etc. Just this small adjustment really made a difference. It is now driving very nicely. Seems that the engine and the tranny are now in sync when before they just were not. Starting off the line is noticeably different as the tranny is not lagging like it used to. It shifts quicker off the line up to the next gear quickly.
I would suggest anyone with an 80 to do the simple FSM procedure to see how their transmission cable is setup. If that little crimped on "stopper" as they call it in the FSM is sitting INSIDE the rubber boot then you need to adjust it so it is slightly outside of the boot and can be seen. This is literally a 5 minute job with a 14mm wrench and done. Smoother, better timed shifts.
Now for a question. I am a little confused from the OP's instructions. There is ONLY ONE cable on the throttle body that directly relates to the transmission and that needs to be adjusted, correct? I know the OP mentioned 2 cables but from what I understand the other one is just the standard throttle pedal cable? Thanks for the clarification.
I would suggest anyone with an 80 to do the simple FSM procedure to see how their transmission cable is setup. If that little crimped on "stopper" as they call it in the FSM is sitting INSIDE the rubber boot then you need to adjust it so it is slightly outside of the boot and can be seen. This is literally a 5 minute job with a 14mm wrench and done. Smoother, better timed shifts.
Now for a question. I am a little confused from the OP's instructions. There is ONLY ONE cable on the throttle body that directly relates to the transmission and that needs to be adjusted, correct? I know the OP mentioned 2 cables but from what I understand the other one is just the standard throttle pedal cable? Thanks for the clarification.
Is setting the plunger to the max more conservative than washer mod?
- Joined
- Jul 20, 2004
- Threads
- 274
- Messages
- 23,205
- Location
- Chandler, AZ
- Website
- www.tontorecreationalliance.org
- Thread starter
- #79
The system line pressure is set by the primary regulator valve, this is the overall pressure setting. The throttle regulator is progressive, reduces pressure at low throttle operation to make shifts smoother in lower throttle operation. At some point (2/3-3/4 throttle depending on adjustment, etc), the throttle regulator is maxed, so is using full system pressure.
Just adjusting the cable will work for some uses. What happens; as it tightened, there is less pressure reduction at lower throttle settings, so firmer shifts. But it reaches system pressure sooner and there is no benefit at full or close to it throttle operation.
By setting the system pressure higher it moves all of the pressures higher. This gives greater range to the throttle adjustment, if anything, may need to back off the cable to to get it where you want, especially for smooth low range operation. It makes a significant difference in most or full throttle operation, like when pulling up a big ledge on the trail, significantly less slip, better compression braking when playing in the rocks, etc.
The other benefit is the way that the cooler works, it's bypass system, it has to be, system pressure is too high (~150-200psi ish) for the lines, cooler, etc. So, the fluid runs all of the things, clutches, bands, torque converter, etc, when it reaches the end, any excess is reduced in pressure and sent to the cooler. When fluid flushing at the cooler, our observation is that the rigs with this mod pump out the fluid quicker than stock rigs, so have higher cooler flow.
- Joined
- Jul 20, 2004
- Threads
- 274
- Messages
- 23,205
- Location
- Chandler, AZ
- Website
- www.tontorecreationalliance.org
- Thread starter
- #80
Correct.
Correct...
Maybe it's just my years of training to do it right, but anytime that I make adjustments like this, I always confirm that the related basic adjustments are correct. In this case, the standard throttle pedal cable, it is often misadjusted, stretched from wear, etc. It only takes a minute to confirm, properly adjust it.
