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Help with 4r70W going forward in reverse, limp mode-error code

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nvrstuk

nvrstuk

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Just a Bronco driver for over 50 yrs!
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Pressure test results

Park - 65

Rev- 65

N- 65

D- 65 (should be first but is t)

2- 40 instantly, then rose to 60

1- 65
 

Viperwolf1

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electron whisperer
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Aug 23, 2007
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24,316
Pressure test results

Park - 65

Rev- 65

N- 65

D- 65 (should be first but is t)

2- 40 instantly, then rose to 60

1- 65

At which test port? I assume Line. If that's the case only reverse looks low. That could be a mechanical problem with the drum seals or a valve body problem. I think there are other issues though.
 
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nvrstuk

nvrstuk

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Just a Bronco driver for over 50 yrs!
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I'm up and running as of 6 hrs ago...

I only checked at the FWD port that Broncobowsher mentioned earlier in the day.

That sent me into the pan. I noticed that the rooster tail or the notched pc that the roller brg rides on wasn't centered ...then I noticed the obvious. Not sure of the proper name and don't have time to look it up but it's the piston rod that moves in and out of the valve body when the shifter moves. The nut that holds the shaft that runs out the side of the tranny with the MLPS on it wasn't visually loose but it wasn't tight enough to keep the "peg" locked into that piston rod and that's why the pressures were the same and that's why the tranny was only in one gear. If I get time when eating breakfast, I'll look up that part and hopefully this will make sense then.


Lot's to do...

Thanks so much for the help...pretty sure you saved our Moab trip!

THANKS for
 
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nvrstuk

nvrstuk

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Just a Bronco driver for over 50 yrs!
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Almost too close! Working great this week!!
Thanks for the help in figuring out which direction I needed to go to find the tranny issue!!
 

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Boss Hugg

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I noticed that the rooster tail or the notched pc that the roller brg rides on wasn't centered ...then I noticed the obvious. Not sure of the proper name and don't have time to look it up but it's the piston rod that moves in and out of the valve body when the shifter moves. The nut that holds the shaft that runs out the side of the tranny with the MLPS on it wasn't visually loose but it wasn't tight enough to keep the "peg" locked into that piston rod and that's why the pressures were the same and that's why the tranny was only in one gear. If I get time when eating breakfast, I'll look up that part and hopefully this will make sense then.


This issue was my first thought when I read that the controller was reading all gears correctly. Logically, just because the electronics are correct, doesn't mean the mechanicals inside are correct. The nut holding the rooster tail on backed off and let the rooster tail "adjust."

Too bad this all went down on a Saturday. I usually don't spend much time here on the weekends, and I'm not sure how I missed this thread since it came up...

Glad you got her did!
 

RADO

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Sep 26, 2016
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Loc.
Phoenix
Almost too close! Working great this week!!
Thanks for the help in figuring out which direction I needed to go to find the tranny issue!!

Nice, glad you got everything running for the trip. I've been in the same situation before... not with a trans problem, but with a Moab trip deadline ruining my life. I learned my lesson.

Did you successfully make it up escalator?
 
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nvrstuk

nvrstuk

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Just a Bronco driver for over 50 yrs!
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So the life lesson was never start a Bronco project!!?? lol. This started out as a basic 4link seat floors lower by 2" and 2" WB increase...done by april...close to on time till installation of the housing with all brackets installed in April and it was WARPED! Warranted but 6 weeks...that's when the D60 with 2 1/2" lift, narrowing both sides of it, moving strg, ORI's on all 4 corners, new wheel wells, moved HB/mc over on firewall (again), , 6" WB increase, cut gas tank down but kept 22 gal capacity (14 lineal feet of new seams on it) list kept growing and I missed a Rubicon run with my Bronco buddies but barely made Moab!!! Whew!!! Strung a taught line so I didn't have another possible 10 mo body project just to be safe. 1st time for me and my spotter--did good. ;)
 
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