Improving Transmission Shifting

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Fwiw, I purchased a trans shift kit for my 96, after I installed my turbo. It was around $100. Was a bit of a pain in the ass to install, but if your opening up the trans, IMO you might as well do it this way. Much firmer shifting, very cool running temps. I added a digital temp gauge. The other day I loaded up my trailer heavy, my rig already weighs in at 8,200lbs. I Drove up a steep canyon with outside temps sitting around 97 degrees. My trans never hit over 170 degrees.

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Fwiw, I purchased a trans shift kit for my 96, after I installed my turbo. It was around $100. Was a bit of a pain in the ass to install, but if your opening up the trans, IMO you might as well do it this way. Much firmer shifting, very cool running temps. I added a digital temp gauge. The other day I loaded up my trailer heavy, my rig already weighs in at 8,200lbs. I Drove up a steep canyon with outside temps sitting around 97 degrees. My trans never hit over 170 degrees.

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Where/how did you install the sensor for the gauge?
 
Where/how did you install the sensor for the gauge?
Toyota already has a transmission sensor on the upper passenger side of the trans. my cruiser in storage or I would snap a pic. I believe this sensor is just an overheat warning sensor and kicks on if there is trouble. I unscrewed the toyota one and put mine directly in to that. it went right in with no threading issues. That being said, make sure you keep the toyota sensor plugged into its adapter / harness after you pull unscrew it. While this (toyota sensor) in effect wont be reading anything, it will however know if its not plugged into the harness, thus triggering a light on your dash. now my new trans temp sensor works perfectly
 
Toyota already has a transmission sensor on the upper passenger side of the trans. my cruiser in storage or I would snap a pic. I believe this sensor is just an overheat warning sensor and kicks on if there is trouble. I unscrewed the toyota one and put mine directly in to that. it went right in with no threading issues. That being said, make sure you keep the toyota sensor plugged into its adapter / harness after you pull unscrew it. While this (toyota sensor) in effect wont be reading anything, it will however know if its not plugged into the harness, thus triggering a light on your dash. now my new trans temp sensor works perfectly
What company supplied the kit or diy, explain more. That looks super nice and thought out. I would be interested in doing that, I don’t run my EGR and I have a scan gage and my coolant temp never runs over 176 normally and never over 185 in the heat of the summer full A/C. It would be nice to know the trans temp tho.
 
search this on amazon

Transgo 340HD2 Reprogramming Kit A343F A340E ('85-'08)​

Should be about $102.00
or try this link...Amazon product ASIN B072LSCXJZ
This does not include the temperature sensor of gauge. it is only the transmission shift kit
 
Those are custom speedhut gauges, installed in a custom delta VS gauge plate. They aren’t cheap, actually, nothing is cheap when it comes to cruisers 😢 The gauges come complete with wiring harness, sensors and fittings.

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So has anyone had an issue in bumping up the pressure regulator on the A343F? Has anyone measured line pressure after adjustment? I know on other transmissions increasing line pressure works great and improves holding up until it's high enough to blow out the seals. Stock pressures aren't too shabby at TC stall.

Looking at the FSM the stock pressures for a '95 are:


Engine Idle​
Torque Converter Stall Speed​
Drive​
61-70 psi​
135-171 psi​
Reverse​
74-88 psi​
188 - 238 psi​
 
So has anyone had an issue in bumping up the pressure regulator on the A343F? Has anyone measured line pressure after adjustment? I know on other transmissions increasing line pressure works great and improves holding up until it's high enough to blow out the seals. Stock pressures aren't too shabby at TC stall.

Looking at the FSM the stock pressures for a '95 are:


Engine Idle​
Torque Converter Stall Speed​
Drive​
61-70 psi​
135-171 psi​
Reverse​
74-88 psi​
188 - 238 psi​

Been running mine with increased line pressure for over 10 years, no problems. But transmission maintenance, use and its general 'health' is going to vary widely among owners. I've owned my Cruiser for 21 of its 24 yrs and have always done the maintenance on it.

It doesn't see a lot of hard use (occasional trailer towing and off-roading), so not abused in any way. Currently at 326K miles, trans is stock aside from the adjustment.

I haven't bothered to check the pressures at the service port....but might do that one day when/if I have nothing better to do.

Pressure Gauge1.jpg
 
Been running mine with increased line pressure for over 10 years, no problems. But transmission maintenance, use and its general 'health' is going to vary widely among owners. I've owned my Cruiser for 21 of its 24 yrs and have always done the maintenance on it.

It doesn't see a lot of hard use (occasional trailer towing and off-roading), so not abused in any way. Currently at 326K miles, trans is stock aside from the adjustment.

I haven't bothered to check the pressures at the service port....but might do that one day when/if I have nothing better to do.

Ok, that's good to hear. I figured if people were seeing a failure soon after they would mention it. Plus if Toyota left the adjustment there I'd hope it doesn't blow things up.

For what it's worth I measured that adjusting from the mid to higher setting adds ~1mm of spring preload to the regulator. If I have some free time after work I can see about putting a gauge on the service port and report some #s.

Also BTW not a bad time to re-torque the valve body. I found 3 bolts on mine that turned at 2.8N*m vs the specified 10 N*m. Transmission appeared to never have been opened up, 175k miles on the clock.
 
Ok, that's good to hear. I figured if people were seeing a failure soon after they would mention it. Plus if Toyota left the adjustment there I'd hope it doesn't blow things up.

For what it's worth I measured that adjusting from the mid to higher setting adds ~1mm of spring preload to the regulator. If I have some free time after work I can see about putting a gauge on the service port and report some #s.

Also BTW not a bad time to re-torque the valve body. I found 3 bolts on mine that turned at 2.8N*m vs the specified 10 N*m. Transmission appeared to never have been opened up, 175k miles on the clock.
So you're happy with the adjustments? I just stumbled across this and now I want to tinker with my transmission. My 80 is heavy. Stock drive train. Shifting sucks 😕. Makes driving an already under-powered truck even more tedious. I love the cruiser but better shifting sounds like it'd be worth the effort.
 
So you're happy with the adjustments? I just stumbled across this and now I want to tinker with my transmission. My 80 is heavy. Stock drive train. Shifting sucks 😕. Makes driving an already under-powered truck even more tedious. I love the cruiser but better shifting sounds like it'd be worth the effort.

I didn't notice any change in shift performance. I haven't had a chance to measure pressures.
 
Can anyone please advise what my options on my electronic a442f. I am keen to fine tune my current shift patterns. It’s all rather clunky as it is.
 
Next is the transmission throttle cable, often called the kick down cable. On older type transmissions it played a roll in shift timing, on the A343F shift timing is controlled by the ECU. Its purpose is to increase system pressure as more throttle/engine torque is delivered. When adjusted tighter shifts are firmer, when looser shifts are smoother.

The first step is to confirm proper throttle cable adjustment. Remove floor mats, gummy bears and any other debris from under the throttle pedal. Under the hood loosen the adjustment nuts on the throttle cable. Have a helper hold the throttle pedal to the floor, pull on the cable housing (the larger black part) hard enough to fully open the throttle plate, turn the outer nut (on the cable housing side) until it touches the bracket, then tighten the other nut (on the cable/linkage side). The goal is to have the throttle butterfly fully open when the pedal hits the stop. If adjusted too tight the cable will stretch/fail.

Now adjust the transmission cable tighter, finding where it works best for your setup and preference takes experimenting. I first had it tighter, almost pushing the boot off, worked well on the road. When in low range, on dirt, would get brief wheel spin when shifting 1st to 2nd, not the best for smooth wheeling?:hillbilly: Moved the adjustment several times until I found the happy spot for my setup/use.

It’s not a modified valve body or shift kit, but made a noticeable difference, especially on the trail. Feels more hooked up, solid, better climbing and compression braking over rocks, etc. The 2nd gearshift is still very firm in low range, but I run 2nd start when in low, except when on obstacles that require 1st gear, so not an issue for me. IMHO for the cost was some RTV sealer for the pan install, ATF to refill the trans and time, it’s a good improvement.

This is where the adjustment on my trans cable ended up.
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Just tried this 12 years later! Thanks!!!!
 
Just tried this 12 years later! Thanks!!!!
Great tech, great writer. Unfortunately, he passed away over 2 years ago. His tech will live on forever, and hopefully so will his shop!
 
IMHO the auto trans is tuned more on the smooth shift side than I prefer. As lift, weight, larger tires, etc, have been added, it has moved more towards a slip shift end of performance.:frown: So, did a bunch of reading, talked to a trans tech buddy and have tried a few tweaks with good results. Wasn’t comfortable posting until I had some trail days on it, over the holidays ran 7 days and 287 trail miles and very happy with the improvement.:hillbilly:

The disclaimer: I’m not a trans expert, so try at your own risk. I have only researched the A343F, this probably wont work on the earlier transmissions?

System line pressure has a direct effect on the holding force of the clutches and brakes. Lower line pressure makes for smoother shifts by allowing more slip, more slip increases wear and running temps. Higher pressure makes for firmer shifts, less slip, wear and IMHO better trail feel/response.

There are two relatively easy adjustments that change the line pressure, first the primary regulator valve. Its job is to regulate the main pump output. It is in the lower valve body, so requires removing the pan.
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When shifting the transmission from D to D, it moves slowly
 
Revived

Doing a 12 quart fluid flush on my 1999 Toyota Land cruiser as well as a filter change so after doing lots of reading I thought I might as well make that adjustment on the line pressure but my cap looks a little bit different from the one at the beginning of this thread.

It has a V mark with three dots and turning it segment to the left appears to be at the same level ... Anybody else noticed this difference?


Before
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After
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Finally got around to knocking out this mod. I've ran a few thousand miles now and pretty happy. Adding a bit more detail to this thread. Looks like each step is 1.5mm. I sat mine to the highest point and added a washer that was 1.59mm. Making mine a fourth step.

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