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ZF4HP22 DELAY IN REVERSE?

5K views 28 replies 6 participants last post by  atakan 
#1 ·
Hello!!!
So I had the lovely experience of ripping a brake line off while offroad in tall grass (collaring a lion so choices had to be made). Later in day on a downhill I lost all brakes, managed to drive into an uphill bank to a sort of stop.
Somewhere in the midst of these two events I also broke the kick down cable.
It broke off from the attachment on the valve body.
New cable installed and valve body put back in, new oil and new O rings for filter.
New shifting issue:
1. Harder shifting
2. Delayed shift into reverse
3. When shifted into reverse, car has hesitation to move.
Any ideas? Doomed?

Car is a 4.2 efi with auto, in a defender. Gearbox worked great before this.

Thanks!
 
#6 ·
Sorry time zone differences. The kick down cable has a fitting that goes onto the valve body, with a small cylindrical plastic fitting. The cable broke at this fitting. To install the new cable and take out the broken one we had to lower the valve body.
Sump is totally fine, there was no oil loss.
 
#9 ·
Sounds like it is low on fluid.

OK got it.
The cable has 2 ends and since it broke underneath, you took the valve body down to replace the kick-down cable.

Did you refill the transmission with the engine running and check the level a few minutes after adding each dose of ATF?
It generally takes 20 to 30 minutes to fill the transmission up and bleed all the air out.
You have to add a little, wait, and then check, repeat until you'll sure it's full all with the engine running and the transmission in neutral.
It's not like topping up the engine oil and you check once and are done.
Since I double check everything, after it's full, I take it for a drive and make sure it goes through all the gears and the torque converter locks which seems like 5 shifts.
Then go into reverse for about 20 feet, then check the ATF again.
If it's low then you have to add more and keep checking.
If it's overfilled, you'll need to drain some out and if it has a diesel engine pour the bit you drained into the fuel tank.
 
#10 ·
Sounds like it is low on fluid.

OK got it.
The cable has 2 ends and since it broke underneath, you took the valve body down to replace the kick-down cable.

Did you refill the transmission with the engine running and check the level a few minutes after adding each dose of ATF?
It generally takes 20 to 30 minutes to fill the transmission up and bleed all the air out.
You have to add a little, wait, and then check, repeat until you'll sure it's full all with the engine running and the transmission in neutral.
It's not like topping up the engine oil and you check once and are done.
Since I double check everything, after it's full, I take it for a drive and make sure it goes through all the gears and the torque converter locks which seems like 5 shifts.
Then go into reverse for about 20 feet, then check the ATF again.
If it's low then you have to add more and keep checking.
If it's overfilled, you'll need to drain some out and if it has a diesel engine pour the bit you drained into the fuel tank.
Thanks for your conclusive answer. Loaded it with about 8lt of fluid. Checking levels when running and in Neutral. It would show empty after 7 lt and only showed up on the dip stock at 8lt.
I will try this bleeding procedure.
Another thing to note is when driving forward in D it will suddenly "kick down" with no real change in throttle input. Soon as you build up some rpm it kicks down. I thought I could chalk that up to cable adjustment but maybe it is related or says something about the reverse issues?

Thanks
 
#11 ·
Can't tell from your reply if the transmission is full or not.
Think all the issues are due to low fluid or kick-down cable adjustment.
Assume you installed a new transmission filter and are using old style red ATF
 
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#12 · (Edited)
Yeap. New filter and olf style dextron 2 ref ATF. Tranny is full. Cleaned valve body again and te installed. No joy. It has "normal" forward drive, but if in D it will kick down harshly. If driven in 1 it will kick up to 2 and wont violently kick down like in D. Also reverse delays to engage and reluctant to move. Reverses as if obstructed.

Will drain and refill as per your recommendation
 
#13 ·
Is the main shift cable moving through all the gears?
You could be in neutral thinking you are in reverse if you're going strictly by what the shifter position reads.
 
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#15 ·
It still sounds like you got the spring too tight or not wound @ all. With the engine turned off if you pull the kick-down cable from the linkage side (TOP) does it retract back on it's own? When installing the new kick-down cable inside the transmission did you wind the spring around @ least once before hooking the new cable on? If not then you are not getting the right amount of pressure through the valve body and this would explain the erratic shifting. It's functioning as if the kick-down cable is nonexistent.
 
#18 ·
Hey Guys. So opened sump,dropped valve body. Found spring. There was almost no tension pulling back cable so wound it once for some tension. Sad to report i still have the same issues. Attached is video of the tension on cable on throttle side, whilst disconnected.

 
#27 ·
So I opened up the valve body. Used up 3m workspace just trying to lay everything out tight. Used petrol and wurth intake cleaner. Ran out of daylight and curfew caught up.
I cant get the bigger inner gaskets for the zf but these look okay... think its futile not to replace?
Nothing seems too out of order. Not too much dirt and the check balls still round etc. I did find a cup washer upside down and the reverse check ball was in a different slot but this must happen as I lifted the block off as I dont see any avenues for play. Will re assemble tomorrow with all the hope possible. Is there really a sure fire way to tension the spring inside the box? Some measurements or stg?
Really hope this valve body clean up works...
 

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#28 ·
So no change with valve body clean up. Still delaying reverse and slipping. And whatever position along the kickdown adjustment having the same symptoms. So box down znd end covers opened. Will start a tear dowm with manuals and photos to guide. Initial inspection shows A clutches really black, the park disc gear had one bolt come off and one really loose, there also appears to be some corrosion on tne governor pulley valve thingi.
 

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