Fzj 80 trans issue (1 Viewer)

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Hello everyone I’m looking for some advice for my 95 Fzj 80 trans issue .

Started today driving with OD engaged . As soon as I hit 50mph it feels like it’s in neutral . Has always shifted fine fluid level is correct . If I pull over then start again it does the same thing at 50mph . If I take it out of OD it will go above 50mph but as soon as I engage OF it has that slip in to neutral effect . Hit the gas no go just revs . Ordered a speed sensor hoping that’s it . Any input or advice would be appreciated.
 
Hello everyone I’m looking for some advice for my 95 Fzj 80 trans issue .

Started today driving with OD engaged . As soon as I hit 50mph it feels like it’s in neutral . Has always shifted fine fluid level is correct . If I pull over then start again it does the same thing at 50mph . If I take it out of OD it will go above 50mph but as soon as I engage OF it has that slip in to neutral effect . Hit the gas no go just revs . Ordered a speed sensor hoping that’s it . Any input or advice would be appreciated.
196k miles. No codes or lights even when it happens . I’m wondering it it could be a solenoid . If I keep my foot on the gas hard enough it won’t have the slip in to neutral feel until I let off . Has me stumped .
 
You'll need the repair manual to go through the troubleshooting matrix (ppg AT-61 through AT-67). It's in the Resources section, but there are two and you don't want unit repair, you want RM479U, ATM repair manual (for use while the transmission is installed).

It's unlikely you have a component fault with no DTC, but it's possible. You do not want to use the shotgun parts cannon to fix an ATM. In a nutshell, the matrix instructions are: 1) check the electrical system and proceed to the component level diagnosis; 2) if no electrical component faults are found, check the ECM. If that fails, 3) open the case.

The numbers in the matrix mean sequential diagnosis areas, for example, if a line has numbers 1, 2, & 3, look at area number 1 first, etc. If a line has only number, that's the problem. The problem is the matrix is somewhat subjective, so if you don't find a problem statement that exactly matches your problem (I looked and I didn't), you'll have to use the closest line(s) and interpolate as best you can. You may have more than one failure mode that are combining to create your failure.

Good news: you don't need overdrive. It exists to save gas.
Bad news: if you have a bad overdrive clutch (one-way or direct) or brake, the only way to fix it is to open the case (that's Chapter 3, off-vehicle repair in the matrix; you'll need the unit repair manual for that).
Really bad news: if you have internal O/D component failure(s), there's likely something else wrong, or about to be soon.

You really need to explore the matrix; you might have a easily repairable or replaceable component that can be fixed without removing the transmission.
 
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Hello everyone I’m looking for some advice for my 95 Fzj 80 trans issue .

Started today driving with OD engaged . As soon as I hit 50mph it feels like it’s in neutral . Has always shifted fine fluid level is correct . If I pull over then start again it does the same thing at 50mph . If I take it out of OD it will go above 50mph but as soon as I engage OF it has that slip in to neutral effect . Hit the gas no go just revs . Ordered a speed sensor hoping that’s it . Any input or advice would be appreciated.
I'm interpreting your description to mean at 50mph and with O/D engaged, the transmission shifts (or appears to) into neutral and although the engine rpm increases, the speed doesn't.

If this is correct, what happens when the speed falls below 50mph? Does the transmission engage, or does it continue to operate as though it's in neutral until you stop? If the transmission doesn't engage as the speed falls below 50mph, with your foot on the gas, what happens when you take your foot off the gas and while it's coasting, put your foot back on the gas?

Have you tried disengaging O/D when the failure occurs? If so, does the transmission engage?
196k miles. No codes or lights even when it happens . I’m wondering it it could be a solenoid . If I keep my foot on the gas hard enough it won’t have the slip in to neutral feel until I let off . Has me stumped .
This sounds like a kickdown cable problem, but I'm guessing here.
 
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I'm interpreting your description to mean at 50mph and with O/D engaged, the transmission shifts (or appears to) into neutral and although the engine rpm increases, the speed doesn't.

If this is correct, what happens when the speed falls below 50mph? Does the transmission engage, or does it continue to operate as though it's in neutral until you stop? If the transmission doesn't engage as the speed falls below 50mph, with your foot on the gas, what happens when you take your foot off the gas and while it's coasting, put your foot back on the gas?

Have you tried disengaging O/D when the failure occurs? If so, does the transmission engage?

This sounds like a kickdown cable problem, but I'm guessing here.
Thanks for the reply Maleus . Cable seems snug but not tight . At any speed if I engage the id it has the slip in to neutral effect . However if I floor it with the OD engaged it stays until I let off the gas . Once I slow down enough probably under 30mph it will Saturday in drive till 50mph if I don’t keep
My foot hard on the pedal . Cruise control works fine . Lockdown cable seems to have the same tension as my other 95 80
That doesn’t have any issues. I saw some vids of solenoids that get plugged up that cause issues with shifting. I have a speed sensor coming today . I’ll start their mess with the cable some more to see if that’s the issue .
 
You'll need the repair manual to go through the troubleshooting matrix (ppg AT-61 through AT-67). It's in the Resources section, but there are two and you don't want unit repair, you want RM479U, ATM repair manual (for use while the transmission is installed).

It's unlikely you have a component fault with no DTC, but it's possible. You do not want to use the shotgun parts cannon to fix an ATM. In a nutshell, the matrix instructions are: 1) check the electrical system and proceed to the component level diagnosis; 2) if no electrical component faults are found, check the ECM. If that fails, 3) open the case.

The numbers in the matrix mean sequential diagnosis areas, for example, if a line has numbers 1, 2, & 3, look at area number 1 first, etc. If a line has only number, that's the problem. The problem is the matrix is somewhat subjective, so if you don't find a problem statement that exactly matches your problem (I looked and I didn't), you'll have to use the closest line(s) and interpolate as best you can. You may have more than one failure mode that are combining to create your failure.

Good news: you don't need overdrive. It exists to save gas.
Bad news: if you have a bad overdrive clutch (one-way or direct) or brake, the only way to fix it is to open the case (that's Chapter 3, off-vehicle repair in the matrix; you'll need the unit repair manual for that).
Really bad news: if you have internal O/D component failure(s), there's likely something else wrong, or about to be soon.

You really need to explore the matrix; you might have an easily repairable or replaceable component that can be fixed without removing the transmission.
Well strange turn of events . I ordered some cheap solenoids off eBay to see if it made a difference . The
Day they show up the problem “went away” . Shifts fine now and hasn’t given me trouble so far . No I didn’t install the new solenoids. I don’t get it I can hit the button to put it in an out of overdrive I’m wondering if something was plugging up one of the solenoids and worked itself out .
I have no idea lol
 
Well strange turn of events . I ordered some cheap solenoids off eBay to see if it made a difference . The
Day they show up the problem “went away” . Shifts fine now and hasn’t given me trouble so far . No I didn’t install the new solenoids. I don’t get it I can hit the button to put it in an out of overdrive I’m wondering if something was plugging up one of the solenoids and worked itself out .
I have no idea lol
Or a bad switch connection?
 

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