Transmission Pan Bolt Failure
#61
Do you know if the LR4 TCM is in the black
plastic housing attached to the valve body? It is on the LR3.
Ford moved to an external TCM on their 6R80 transmissions where that black plastic housing is just an electrical connector with a couple of built-in speed sensors like you’re seeing with yours.
Ford had trouble with their speed sensors failing potentially causing an unexpected downshift like when you’re doing 80 on the freeway and all of a sudden your trans thinks you’re doing 20. They recalled some and extended warranties on some. I have 2 in my family fleet and replaced them both myself before they were recalled. Ford calls it a leadframe, not a TCM.
If the LR4 did the same thing, then maybe you have the same Ford problem. It’s just a guess for me based on my Ford experience. I don’t have any LR4 resources to dig deeper.
I do like your plan of attack above. Just throwing this out for additional thought.
plastic housing attached to the valve body? It is on the LR3.
Ford moved to an external TCM on their 6R80 transmissions where that black plastic housing is just an electrical connector with a couple of built-in speed sensors like you’re seeing with yours.
Ford had trouble with their speed sensors failing potentially causing an unexpected downshift like when you’re doing 80 on the freeway and all of a sudden your trans thinks you’re doing 20. They recalled some and extended warranties on some. I have 2 in my family fleet and replaced them both myself before they were recalled. Ford calls it a leadframe, not a TCM.
If the LR4 did the same thing, then maybe you have the same Ford problem. It’s just a guess for me based on my Ford experience. I don’t have any LR4 resources to dig deeper.
I do like your plan of attack above. Just throwing this out for additional thought.
#62
Here is a screenshot I took a few years ago. It'll give you an idea what the readout formats should be. This was with the engine running in Park. 2006 LR3 4.0L V6 But yours being an LR4... could be completely different. I looked under the hood at a 2012 LR4 recently and I noticed it did not have a Transfer Case module behind the battery like a LR3 does, so there are major electrical differences between the 3 and 4's. If you pull the valve body again, make sure to clean all the residual crap off all the parts. You may also consider replacing the foam insulator gasket behind the shift solenoids as crap can build up there and cause issues. You may also want to look at the shift solenoid live values to see if something is acting up there. Battery voltage is also critical. I've noticed sluggish shifting and flaring if the battery voltage is low...
#63
Have you inspected the pins on the TCM? Sometimes they get bent. When I was diagnosing my fault I put a scope on them to verify they were OK (see photo).
If you do have bad pins or find that the speed sensors are bad then you can try to send it to these guys: https://www.softelectronic.com
They specialize in TCM repairs. I was referred to them when I thought I might have a broken TCM pin. A new TCM is about $2500, so shipping to Europe for this repair is comparatively economical.
The only other thought I have is perhaps part of the old bridge seal gasket stayed on the valve body when you installed the new one. This happened to me and I only noticed it when the valve body wasn’t sitting right after torquing all the screws. You mentioned some trouble with the bridge seal earlier. If the valve body isn’t aligned properly then those speed sensors will be out of range for reading.
If you do have bad pins or find that the speed sensors are bad then you can try to send it to these guys: https://www.softelectronic.com
They specialize in TCM repairs. I was referred to them when I thought I might have a broken TCM pin. A new TCM is about $2500, so shipping to Europe for this repair is comparatively economical.
The only other thought I have is perhaps part of the old bridge seal gasket stayed on the valve body when you installed the new one. This happened to me and I only noticed it when the valve body wasn’t sitting right after torquing all the screws. You mentioned some trouble with the bridge seal earlier. If the valve body isn’t aligned properly then those speed sensors will be out of range for reading.
#64
Thanks for all the ideas to try! If end up pulling valve body down again, I'll certainly check all these things out.
****ty photo below from my phone, but I don't think any of the pins look bent.
Another possibility is that the sleeve isn't inserted all the way and thus not a solid connection.. I measured it at right around 3mm but may have been 4.. really tough to get in there with the calipers. It does look like I have a wider gap than the documentation I've seen, but also that white tab slid upwards with no resistance, and it's close enough that maybe it's okay? (see photo below, mine on the left) If it gets opened up again, I'll need to reseat the sleeve anyway to get the valve body down.
I also came across softelectronics in my research. If I can't figure this out myself I'll have to decide whether to take to the local LR indie or ship her off to Europe.
My live reading from the transmission definitely look suspect with multiple N/A's. I'll check those other values that were mentioned above.
****ty photo below from my phone, but I don't think any of the pins look bent.
Another possibility is that the sleeve isn't inserted all the way and thus not a solid connection.. I measured it at right around 3mm but may have been 4.. really tough to get in there with the calipers. It does look like I have a wider gap than the documentation I've seen, but also that white tab slid upwards with no resistance, and it's close enough that maybe it's okay? (see photo below, mine on the left) If it gets opened up again, I'll need to reseat the sleeve anyway to get the valve body down.
I also came across softelectronics in my research. If I can't figure this out myself I'll have to decide whether to take to the local LR indie or ship her off to Europe.
My live reading from the transmission definitely look suspect with multiple N/A's. I'll check those other values that were mentioned above.
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SeattleDriver (02-16-2023)
#65
I think you’re on to something here. I have replaced about 6 of these sleeves. All difficult to perfectly align and free up the white latch to move into the locking position.
The latch is designed to not move until the little nubs on the sleeve press just exactly right and allow the latch to move upward. If yours went in really easy, that’s suspicious in my experience. And yes, it does look like it’s not all the way inserted in your pic.
The latch is designed to not move until the little nubs on the sleeve press just exactly right and allow the latch to move upward. If yours went in really easy, that’s suspicious in my experience. And yes, it does look like it’s not all the way inserted in your pic.
#66
added another half liter so the initial fill may have been low.
was able to compare low range gear change behavior to a friends LR3 and it behaves identically so im less worried now about the clunky shifts in and out of Park while in low range.
sprayed male and female pins of the connector with contact clear, then tried to press the sleeve in some more without dropping the oil pan.
still getting n/a reading from most of the transmission live values..
When i did the oil change, the white tab didn’t slide up with literally zero resistance. It also wasn’t difficult to push it up, so it felt slotted in correctly.
at this point thinking about it more, I don’t see how resetting adaptations would bring all those live values back. Also if I weren’t looking for live values from the transmission, there would be zero indication anything is amiss, because the gap took shows zero faults!
Should I just reset adaptations and leave it alone?
was able to compare low range gear change behavior to a friends LR3 and it behaves identically so im less worried now about the clunky shifts in and out of Park while in low range.
sprayed male and female pins of the connector with contact clear, then tried to press the sleeve in some more without dropping the oil pan.
still getting n/a reading from most of the transmission live values..
When i did the oil change, the white tab didn’t slide up with literally zero resistance. It also wasn’t difficult to push it up, so it felt slotted in correctly.
at this point thinking about it more, I don’t see how resetting adaptations would bring all those live values back. Also if I weren’t looking for live values from the transmission, there would be zero indication anything is amiss, because the gap took shows zero faults!
Should I just reset adaptations and leave it alone?
#68
Not a failure as such but i had shift issues that were getting worse so thought i better check the fluid level, as soon as i remover the cover i noticed i had a leak at the rear of the pan (never on the ground though) , checked the bolts and found one really loose and a few that needed nipping up.
I did the steel pan upgraded maybe 2 years ago and i used a torque wrench and the correct order when doing up the bolts so either i missed one or they worked loose, did a fluid drain and refill and it was 1L short so it lost a bit.
Reset the adaptions and a drive around the block showed improvement but will see how it goes over the week when i get to 100kph on the freeway.
I did the steel pan upgraded maybe 2 years ago and i used a torque wrench and the correct order when doing up the bolts so either i missed one or they worked loose, did a fluid drain and refill and it was 1L short so it lost a bit.
Reset the adaptions and a drive around the block showed improvement but will see how it goes over the week when i get to 100kph on the freeway.
#70
We are at a bit of a disadvantage for advice since our LR3 have a ZF 6HP26. However, I’d say that the N/A live values are not normal and a problem is still present. My best guess from everything shared so far is that at least one pin in your connector is not making full contact with the male end of the TCM. One of your earlier photos showed a female pin sunken .5-1.0 mm deeper than the others, add to that the additional 1.0mm gap in the plug currently present and there is good reason to think an electrical conductivity problem exists, possibly intermittently. I’d schedule some time, just an hour, with a LR shop or ZF transmission mechanic for a diagnostic. Money well spent in my opinion.
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