1993 FZJ80 Transmission slips in forward gears

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the "mudding" and pressure washing could certainly be the culprits for an electrical issue. i would definetly unplug each transmission related component, clean it up, in spect, apply some dieletric grease and put them back together. make sure you check the speed sensor as well. most people neglect to do so.

however, the physical symptoms you're experiencing seem to be fairly consistant and can just about be duplicated given the proper circumstnaces. and the issue only happens under those conditions. is that correct?

if so, then you're mostlikely dealing with a mechanical malfunction, not an electrical problem.

given the milage on the transmission, that's not really out of the picture. i think it may be a wise idea for you to take this cruiser to a good transmission shop. tell them about all the "research" you've done and let them try to diagnose it. a lot of independant shops will do it for nothing or next to nothing. the diagnostic test should include scanning the computer for any codes ( both instnat and memory ) as well as a driveability test. don't go to aamco, they'll just end up milking you for all you're worth.

i spent 12 years of my professional life in the transmission industrie...............

georg @ valley hybrids
 
orangefj45 said:
the "mudding" and pressure washing could certainly be the culprits for an electrical issue. i would definetly unplug each transmission related component, clean it up, in spect, apply some dieletric grease and put them back together. make sure you check the speed sensor as well. most people neglect to do so.

however, the physical symptoms you're experiencing seem to be fairly consistant and can just about be duplicated given the proper circumstnaces. and the issue only happens under those conditions. is that correct?

if so, then you're mostlikely dealing with a mechanical malfunction, not an electrical problem.

given the milage on the transmission, that's not really out of the picture. i think it may be a wise idea for you to take this cruiser to a good transmission shop. tell them about all the "research" you've done and let them try to diagnose it. a lot of independant shops will do it for nothing or next to nothing. the diagnostic test should include scanning the computer for any codes ( both instnat and memory ) as well as a driveability test. don't go to aamco, they'll just end up milking you for all you're worth.

i spent 12 years of my professional life in the transmission industrie...............

georg @ valley hybrids
Click to expand...

Thank you for your input, Georg. I have done everything from inspecting the solenoids to inspection of the plugs. Through all of this I have not found anything suspect, so I think it is time to get a "new" transmission or get this one completely rebuilt.

I have received a rebuild quotation of $2800.00 from a reputable shop that is familiar with this particular transmission and who also came highly recommended by a local Cruiser mechanic.

However, I have also found that I can get a rebuilt transmission for $1800.00 with a one year warranty; the price goes higher with the extension of that warranty. I may go this route, or buy one with low miles from 'Mud.

Either way, I am done with it. I already spent all I had buying this truck, and now this.

Thanks again for all your input.
 
https://forum.ih8mud.com/80-series-tech/348943-transmission-shifting-issue.html <------LINK



Now I read thru all the posts, the bulbs you for the dash lights are cheap, Less than the price of a latte.

I have my old solonoids, I never tested them because when I pulled the codes I trusted the codes.

Spent the 330.00 for two new solonoids and am pleased with the results. One thing I wonder/worry about is.

That fine derbi on the magnets, it would seem that said debri could easily get lodged in the solonoid body causeing the solonoids to fail.

I have been driving my rig with the new solonoids for awhile and- its shifts much firmer. I no longer drive around in the "power" mode.

I was told when I got the rig that some people drive around in the "power" mode all the time because it gives you firmer shifts.

I found that the new solonoids give you firmer shifts- Period. (Power mode is even firmer)

-good luck-

Another thing- how dose you parking brake work? I am wondering if there is any corralation between the solonoids and a bad parking brake.
 
spdwaver1 said:
... When facing uphill in neutral, I would allow the vehicle to roll backward very slowly, then put it into drive. It causes the problem to happen every time, without fail. I could feel the transmission engage, but very slow forward motion at about 1800 RPM.
Click to expand...

This sounds normal, at least for my rig (A343F trans). The torque converter stall is ~2000rpm, doesn't start to pull till ~1800rpm.

Has it set any additional codes?

spdwaver1 said:
...
Either way, I am done with it. ...
Click to expand...

It's imposable to get a "feel" for the problem over the net and explaining it with text isn't much better. I would contact Georg, talk to him and if possible take a road trip and have him drive it?
 
Jason YY said:
https://forum.ih8mud.com/80-series-tech/348943-transmission-shifting-issue.html <------LINK



Now I read thru all the posts, the bulbs you for the dash lights are cheap, Less than the price of a latte.

I have my old solonoids, I never tested them because when I pulled the codes I trusted the codes.

Spent the 330.00 for two new solonoids and am pleased with the results. One thing I wonder/worry about is.

That fine derbi on the magnets, it would seem that said debri could easily get lodged in the solonoid body causeing the solonoids to fail.

I have been driving my rig with the new solonoids for awhile and- its shifts much firmer. I no longer drive around in the "power" mode.

I was told when I got the rig that some people drive around in the "power" mode all the time because it gives you firmer shifts.

I found that the new solonoids give you firmer shifts- Period. (Power mode is even firmer)

-good luck-

Another thing- how dose you parking brake work? I am wondering if there is any corralation between the solonoids and a bad parking brake.
Click to expand...

I am now (last night) getting code 62 and 63 as well. Maybe my solenoids are just fading out of service? Inspection and testing seemed to prove otherwise. Does not seems likely, but possible nevertheless.

I will take my chances and change out the solenoids since this is the overwhelming consensus, and since CDan has spoken.


My parking brake does not work well at all.
 
spdwaver1 said:
I am now (last night) getting code 62 and 63 as well. Maybe my solenoids are just fading out of service? Inspection and testing seemed to prove otherwise. Does not seems likely, but possible nevertheless.

I will take my chances and change out the solenoids since this is the overwhelming consensus, and since CDan has spoken.


My parking brake does not work well at all.
Click to expand...

In a what I concider odd experience-
After I pulled the codes- I started getting a flashing O/D light. That was after I pulled the "dome" fuse to reset the system.

Anyway looking at the solonoid it would seem that perhaps an issue with them could be, a bad O ring where the slips into the tranny? Perhaps fluid under preasure bypassing the solonoid?


FYI- in my case I just went with what C-dan said (and the FSM)

There didn't seem to be much info on Mudd (specifically RE the Solonoids)
 
Jason YY said:
In a what I concider odd experience-
After I pulled the codes- I started getting a flashing O/D light. That was after I pulled the "dome" fuse to reset the system.

Anyway looking at the solonoid it would seem that perhaps an issue with them could be, a bad O ring where the slips into the tranny? Perhaps fluid under preasure bypassing the solonoid?


FYI- in my case I just went with what C-dan said (and the FSM)

There didn't seem to be much info on Mudd (specifically RE the Solonoids)
Click to expand...

I got the flashing OD light last night as I was driving up the freeway: "OD OFF" (2 second pause) "OD OFF" (2 second pause).

I suppose CDan will be getting a phone call really soon (if that Jeep sells).

Thanks for posting your results, this has helped tremendously. :cheers:
 
I have ordered 2ea. 85420-60050 shift solenoid from Cruiserdan, so I will update the thread once I install and test them.
 
I just received my solenoids in the mail (thanks Dan!) I will be installing these tonight and will report my findings later, after I get quite a few test miles on it.
 
Took it out for a few miles after I changed the solenoids, climbed a few hills in the process and noticed an immediate change: I did not need to mash down the accelerator and did not need the ECT activated.

Not one instance of slipping, but it is too early to tell if that fixed it; but I do believe that it did.
 
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raydouble said:
Awesome Sean :cheers:

Hopefully it will solve your issue for good.
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Dave 2000 said:
I am so anti automatic it's untrue however, here I am thinking about it as the manuals are a bit rare in the UK market. Good to see you stuck it out and I hope you have it sorted.

regards

Dave
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Thank you for the kind words. There really is a notable difference in feel and performance; I did not realize it at the time, but it had not been performing up to standard.

We'll see how it does after about a week.
 
Well, to sum it all up, the solenoids were indeed the problem. I have not had one single incident where the transmission seemed (or actually was) starting out in second or third gear from a stop.

Thanks to everyone who provided their input; without which I could have spent significantly more in repairs or replacement.

Again, Cruiserdan called it. :cheers:
 
As an afterthought, I wonder what sort of damage, if any, could result from starting out in third gear over time. For example: if you could force the transmission to start out in second or third at any time, would there would be clutch wear as a result?
 
Tools R Us said:
Good deal!:cheers:
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It is a good deal, every way you look at it. At first glance, one could say that these solenoids are too expensive for what they are; but not so expensive when you consider the alternative to fixing it yourself.

calstyl2 said:
Never Doubt the Cdan(unless its a 40/45/55) He knows those 80s.
Click to expand...

I agree.
 
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