Anyone tried this? (auto trans mod)

Joined
Jun 22, 2005
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I was having problems with my auto not downshifting the way I think it should. Having not driven many 80 autos I couldn't say for sure the behavior was normal.

Basically if you slowed down to about 20kph (that's what 12mph?) it would stay in 3rd gear and not downshift unless you floored it, which would then cause it to downshift to 1st and you'd rocket away at full throttle.

Also is it down shift or up shift? I can never remember. You go down in gear numbers, but up in ratios - very ambiguous terms.


Anyhoo to get around the problem I did the pin 7 mod, and then disconnected the low range switch plug from the transfer and shorted it permanently causing the trans computer to run in the low range shift pattern all the time.

The results I've found are very dramatic. It runs up and down the gears the way it should. Only draw backs are you get no torque converter lock up, and the upshifting out of first doesn't happen until about 2400rpm. similarly it won't up shift out of 2nd until about 40kph. In short it holds the gears as you would expect it to in low range.
When It comes to downshifting, it does so automatically when you go under certain speeds (40kph for 2nd, 20 for 1st). This is opposed to the normal behaviour where you have to press the throttle some. This gives it the feeling that it's always in the right gear to get going when you slow down for whatever reason. It also feels like you get more engine braking.

Personally I like the new performance. It might interest some who are after a more 'manual transmission' or performance feel. It hasn't really effected economy either.

I was thinking it would be possible to install a switch that enabled you to select the low range pattern without having to do the pin 7 mod - if you wanted to. A kind of 'POWER!' button opposed to the standard 'power' mode (notice the capital letters and exclamation mark)
 
Joined
Jun 22, 2010
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Boston, MA.
interesting.. My truck shifts just fine but could be interesting to have a big POWER! Button :p i cant imagine that your mpg is not going to diminish significantly rocking around in1st and 2nd gear all the time in town though...
 

sl33p3

still waking up...
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I was having problems with my auto not downshifting the way I think it should. Having not driven many 80 autos I couldn't say for sure the behavior was normal.

Basically if you slowed down to about 20kph (that's what 12mph?) it would stay in 3rd gear and not downshift unless you floored it, which would then cause it to downshift to 1st and you'd rocket away at full throttle.

Also is it down shift or up shift? I can never remember. You go down in gear numbers, but up in ratios - very ambiguous terms.


Anyhoo to get around the problem I did the pin 7 mod, and then disconnected the low range switch plug from the transfer and shorted it permanently causing the trans computer to run in the low range shift pattern all the time.

The results I've found are very dramatic. It runs up and down the gears the way it should. Only draw backs are you get no torque converter lock up, and the upshifting out of first doesn't happen until about 2400rpm. similarly it won't up shift out of 2nd until about 40kph. In short it holds the gears as you would expect it to in low range.
When It comes to downshifting, it does so automatically when you go under certain speeds (40kph for 2nd, 20 for 1st). This is opposed to the normal behaviour where you have to press the throttle some. This gives it the feeling that it's always in the right gear to get going when you slow down for whatever reason. It also feels like you get more engine braking.

Personally I like the new performance. It might interest some who are after a more 'manual transmission' or performance feel. It hasn't really effected economy either.

I was thinking it would be possible to install a switch that enabled you to select the low range pattern without having to do the pin 7 mod - if you wanted to. A kind of 'POWER!' button opposed to the standard 'power' mode (notice the capital letters and exclamation mark)

interesting result. did you ever play with/replace the throttle kick down cable? too loose and shift points are all sucky, kickdown doesn't happen stomping on the pedal... over-tighten and it kicks down when you look at the throttle and 4lo will bark tires shifting into 2nd, ok we know it can't bark, but it does throw your head against the headrest and slip tires in the dirt.

i have put mine in a happy medium place (after replacement) with quite a bit of fiddling (but the adjustment is so easy with 2 14mm wrenches)and since a new cable has no ferrule marker, i couldn't tell you how it compares to a new(old) cable.

i CAN tell you after replacing my 442 and putting in a temp gauge sender before and after the trans cooler, that no TC lockout will push trans temps pretty high on any grade at speed (not to mention fuel efficiency on the highway). i am at 7k' so i'm working hard to move already, but i frequently kickoff OD so i can lock TC in 3rd and bring temps back down. but i am paranoid and overattentive since i DO NOT want to put in another tranny and too much heat is baaad mm'kaayy... (i can keep mine sub 200F most the time) trans temps are VERY volatile up and down under TC slip and load IME.

shrug
 
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Joined
Dec 22, 2010
Messages
329
Why not just tighten up the kickdown cable a few threads as they stretch over time. IMHO, not having the torque converter lock up for highway cruising is NOT a minor drawback.

I just tensioned the kickdown cable on ours and the difference is night and day. it downshifts when it should and is soooo much zippier to drive. Just a few thread turns is all you need...
 
Joined
Dec 27, 2009
Messages
134
A button to change shift patterns to the 4lo ones is pretty cool for twisty trails and times when you want the the motor in its powerband all the time, but not to fix your problem. R & R your kickdown cable and set it properly. You'll find if your rig has the ECT button with a new cable, it will feel like night and day with the power setting on.
 
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To answer some questions.

I'm not concerned about transmission temps.
1. the light never comes on
2. under full load, the TC unlocks anyway
3. before the 70's oil crisis locking torque converters were unheard of
4. the a442 transmission is overkill for the 80 series. The extra load won't be a problem. I change the fluid more in line with the 'severe' conditions in the manual anyway.

It does shift into 4th (overdrive). However it doesn't really do it until low throttle input. Depending on how you are driving in low range, for example on sand, you may never actually get close enough to zero throttle for the trans to shift making it seem like it doesn't go in.

I've fiddled to no end with the throttle cable as described in all the transmission threads i read here on mud. My problem wasn't totally consistant with others. Two things that lead me to believe the ecu was faulty is 1. It doesn't log error codes when clearly it should. eg. I unplugged the solenoid wiring to manually test the trans per the FSM but no error was logged, contrary to what the FSM said would happen.
2. From what i've read, the throttle cable only controls line pressure in the transmission in relation to engine load. Everything to do with shifting is done electronically, and the main input in normal mode is the throttle position sensor. The TPS tested fine, and no code related to it has come up on the engine side of things.

My fix is a bodge job i admit. I would test the ECT ECU and wiring further but it is very inconveniently located up under the steering wheel. Given the after effects, and the cost (not even a whole paperclip ;)) i'm more than happy with how the tranny works in it's current state.

A few after thoughts though: Any mpg increase is not noticeable. It may average out since in some driving conditions I would be using less throttle at a higher rpm, opposed to more throttle at a lower rpm

And secondly, I don't have ABS. It's actually rare on Australian 80 series. Since ABS is disabled normally in low range, this would be a further obstacle to over come.

I'm not suggesting people go out and try it just for s***s and giggles, but I thought I would post up my experiences for anyone out there interested.
 
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Joined
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interesting result. did you ever play with/replace the throttle kick down cable? too loose and shift points are all sucky, kickdown doesn't happen stomping on the pedal... over-tighten and it kicks down when you look at the throttle and 4lo will bark tires shifting into 2nd, ok we know it can't bark, but it does throw your head against the headrest and slip tires in the dirt.

THANKS for this. :cheers:

I've had this issue since I got my cruiser a year ago. I adjusted my kickdown cable - loosened it about 10 revolutions - now my 4-low shifts are normal, AND as a bonus my 4-high (regular) starts are a LOT smoother! Which has bothered me since day 1. It felt like my throttle cable was sticky. But it was just this 2 minute adjustment needed! :beer:
https://forum.ih8mud.com/80-series-tech/451498-transmission-shifting-high-rpm.html
 

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