ZF 8HP refill - showing full before replacing amount drained

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cannondale900

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I just completed the pan/filter, fluid, and mech sleeve replacement (my old mech sleeve was not leaking) at 71k miles. I drained ~5.5qts from the transmission after loosening the mech unit but not fully dropping. Only 4 qts made it back in before indicating full. I used the following procedures:
1) Lift in my garage is level as per 4ft carpenters level (so car was "level")
2) Filled cold to point of leaking out fill opening then capped
3) Run engine to 2k rpm for 30 secs
4) Shift manually through R/N/D/S1/S2 and get temp to range 105F-122F
5) Top off until fluid leaking out fill opening then capped
6) Reset adaptations with IID Tool

I took the car for a test drive and the previously worsening jolts when putting in to R/N/D are gone which is nice. Drove car through range of speeds and gear both in D and S modes. On right hand turns while accelerating the car will not shift to next gear and I assume it is because pump is cavitating due to being 2 qts low and fluid shifting to left side of trans (it looked like pump pickup was on right side.)

Any thoughts/tricks to find room for 2qts more capacity?

Thanks!
 

cannondale900

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So uh yeah.......engine needs to be running while filling. I've only serviced manuals to this point. Good thing was that I knew something wasn't quite right so I took it easy on the test drive.

Lesson learned folks.....now on to the 6hp in my 2010 535 wagon?
 

DaytonaRS7

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i recently did this on my 2011 LR4 with ZF 6HP, and yes, engine must be running when you top off the fluid.

1. drain, change pan/filter if necessary
2. on level ground, fill until fluid drip out of fill hole.
3. loosely install fill plug
4. start car, shift though gears (PRND) run engine until pan measures 40-50 degrees celcius. use a infrared thermometer.
5. remove fill plug, add fluid until it drips out of fill hole. this is actually the only critical time the only time the car must be on level ground.
6. reinstall and tighten fill plug.


A few tips i learned

DIY fluid transfer pump:
Use a pump sprayer bottle to fill fluid. cut off the "wand" just after the handle, leave about 2" of the hard "wand". Slide a 5' long clear plastic hose (i think it was 5/16" or 3/8" ID) over the remaining 2" of hard plastic "wand", tighten a hose clamp around it. fill bottle with fluid, pump, use handle to start/stop fluid flow.
https://www.homedepot.com/p/Chapin-...VAm6GCh3TfgvwEAQYASABEgLBF_D_BwE&gclsrc=aw.ds

If you don't have a lift and are struggling with the getting under the car to top of the fluid, this is what I did:
1. drive car on ramps.
2. remove fill plug, insert clear hose. route the hose it so it is not touching the exhaust. there was a rubber exhaust mount that i was able to use and brace the hose against so it would stay in place and not melt.
3. The clear plastic hose should be long enough so that you can sit at the side of the car and add fluid
4. with car on ramps, add fluid until it comes out of fill hole
5. slide under remove hose and very loosely install fill plug.
4. start car, back car off ramps.
5. Shift though gears (step 4 above).
6. move drivers (left) ramp away from car. leave passenger (right) ramp in place.
7. measure pan temp, when it reaches 38 degree celcius, pull car up onto passenger ramp only.
8. wearing mechanics gloves (to prevent burns) with car still running, slide under and remove fill plug, insert clear pump hose. brace as you did in step 2. move pump bottle to side of car, with enough loose hose so car can back off the ramp.
9. back off ramp, with hose still inserted in fill hole.
10. fill transmission until fluid come out the fill hole. DO NOT SHUT CAR OFF FROM THIS STEP FORWARD UNTIL FILL PLUG IS IN PLACE.
11. pull forward onto passenger(right) side ramp again. this will shift fluid away from fill hole so you can "cleanly" reinstall fill plug, while keeping the fluid from dripping out.
12. slide under car, remove fill hose, install and tighten fill plug.
13. shut car off.

This was by far the cleanest and easiest way i was able to fill the transmission. the only fluid spilled was the drips out of the transmission, and the small amount that dripped out of the hose when removed from the fill hole. cheap hand pump fluid transfer pumps are terribly messy and tiring to use. combine that with the fact that you need to fill while on level ground, anyone without a lift will struggle with this.
 
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mbw

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I am about to redo my pan gasket. I like the idea that @DaytonaRS7 mentioned with the pump sprayer so I went to make one. I got a 1 gallon one for under $10 and instead of cutting off the end, just pushed some hose over the end with the little spray cap taken off and then put a right angle push fitting into it. I think this will work.

Last time I used my mittyvac, but its a bit awkward to get the hose bent into there and keep it from touching the cat. Plus i had to reach a long way to pump it or release preasure, etc. This was cheap and ill have precise control of the fluid.

IMG_1151-X3.jpg
 

ambrown31

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I would also highly recommend buying an inexpensive scan tool that can tell you trans fluid temperature. I found measuring the pan to give a lot of variation and I could never get a reading that was even close to the fluid temperature my scan tool showed.

It also took much longer than a minute or two to get up to temp from cold. I am thinking it took about 15 minutes or more of idling going through all of the gears before it was at fill temperature. This was on an LR3.
 

NeilP

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The temp of fluid is a volume measuring procedure . As long as the engine is running and had the gearshift worked through as described , I've found that anything fairly blood-temp is close enough . There's still air in the system , and there's not going to be a problem like a water boiler with no pressure vent . Whether or not one replaces the transmission pan and it's filter depends ( imho ) upon whether the oil sample taken is decent or dreadful . I've seen quite black oil and gunge stuck all over the plastic pan that you really do want removed . If it's OK , then oil-only saves a lot of expense and trouble . I had the diffs , transfer case and transmission fluids in my LR3 ZF6 replaced at 75,000 miles . The pan base/filter was done too , as it was an all-in job which I wanted . Holds much better now . I can feel more friction pulling up inclines , and the fuel economy has improved . The changes are smoother too , but not like new or like a ZF8 though . Hot climates and towing take their toll , so work to your own conditions . Thanks for typing the procedure up guys for those wanting to know :)
 

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