2010 LR4 transmission fault

[Jimmy Brooks]

My Land Rover LR4 has been the most Land Rover my family has ever owned. All of that changes one summer in about 2016 when the car had about 90,000 miles on it and it threw a transmission fault on a very hot day. Ever since that day if you drive the car for about an hour straight and it is 90° (a normal California day) the transmission will bump trying to shift up from 3-4 gear. (Note in the morning when the transmission isn’t warmed up you can feel it shifting from 3-4 but all other gears are smooth, this only happens when shifting up from 3-4 but not down) We dropped a transmission rebuild in it for about $6,500 and the issue was still happening. After taking it back in 10 times and the only improvement was that it didn’t happen as much but was still there, we gave up on it and won’t take it on long commutes anymore. I wanted to see if any of you possibly know what the problem could be and over time I’ve also made a few notes on this issue. The problem happens only when it is up shifting from 3-4 and not a lot of gas is applied. In the process of shifting it will rev up, the acceleration will stop as if it goes into neutral then, after a long second it will go into 4th. It is much more common for it to occur once put into sports and only happens when you’ve been driving for awhile. Please let me know what you guys think it is any suggestions will help, Thanks.

 

[ryanjl]

If you dropped a rebuild in it and it's still giving you problems, I'd be curious what the "rebuild" entailed. Did they reuse your old mechatronix unit? Did they reset the values in the computer?

 

[Jimmy Brooks]

If you dropped a rebuild in it and it's still giving you problems, I'd be curious what the "rebuild" entailed. Did they reuse your old mechatronix unit? Did they reset the values in the computer?

now that I have done a little research on what a mechatronic unit it is I believe that you are right that they have not replaced the unit. It would be the only thing that would make sense. Do you possibly know what model/part # of the ZF transmission my 2010 LR4 has in it. It has the 5.0 V8 in it.

 

[ryanjl]

ZF 6HP26. You may need to replace the solenoids, but those generally throw a code if they are bad.

I've posted this video on here before:

Watch that and see if it gives you any ideas.

 

[Jimmy Brooks]

ZF 6HP26. You may need to replace the solenoids, but those generally throw a code if they are bad.

I've posted this video on here before:

Watch that and see if it gives you any ideas.

You are literally a life saver I can’t describe how thankful I am that you happened to respond to my post and I mean that when I say it. I believe they did at one point replace a couple of the solenoids because the car did end up throwing a couple of engines lights when this happened and it bumped super hard and then it stopped throwing engine lights when it faulted/bumped but I believe it’s the rubber piece leaking making the solenoid not able to grab enough fluid to be able to shift. I believe this because of an article I read earlier, I’ll attach a screenshot down blow, and your video has confirmed it. Thank you so much for all your help it means the world to me to know I can finally get my LR4 running back as if it’s new and take it on long road trips and off road adventures.

 

[avslash]

parts and instructions to replace the bridge/seals are available here: http://www.thectsc.com/tree-faq

 

[scott schmerge]

I’m looking at your rpms at 80mph. That’s high to have them running at 4000. Do they increase significantly when it faults? Is that when it’s between gears? Are you sure it’s 3-4? Doing 85-90 mph, I’d assume you’re in 5-6th (1st gear is very short). Is it giving you a code incorrect gear ratio? What are the codes when it faults?

Not convinced it’s your bridge but could be the mechatronic unit itself. They do fail

 

[werdnash2002]

I have the exact same issue and am trying to confirm if I need a new transmission or its just the mechantronic hoses and sleeves. Mine only slips as the op says, when on a 20% incline. Mine is throwing a code for 5th gear incorrect ratio (P0735-07) as well as P2704-07 Transmission friction element E apply time range/performance (Mechanical failure) The video above seems to say if your getting incorrect gear ratio codes its likely the mechatronic sleeves. However the other code from my research is usually an indicator you need a new transmission or a rebuild. The car drives flawlessly expect going up mountains/steep hills in high gear and the ocassional 2-1 clunk (also video says a sign of bad mechantronic sleeves) anyone have any feedback on these codes?

 

[TrinidadLR4]

You have a 6hp28. Based on symptoms, maybe the bridge seal(behind mechatronics unit) has cracked and the unit isn't holding pressure anymore. I am about to replace this part myself, as preventative maintenance.

 

[Pablitovil]

I have the exact same issue and am trying to confirm if I need a new transmission or its just the mechantronic hoses and sleeves. Mine only slips as the op says, when on a 20% incline. Mine is throwing a code for 5th gear incorrect ratio (P0735-07) as well as P2704-07 Transmission friction element E apply time range/performance (Mechanical failure) The video above seems to say if your getting incorrect gear ratio codes its likely the mechatronic sleeves. However the other code from my research is usually an indicator you need a new transmission or a rebuild. The car drives flawlessly expect going up mountains/steep hills in high gear and the ocassional 2-1 clunk (also video says a sign of bad mechantronic sleeves) anyone have any feedback on these codes?

I have the exact same issue and am trying to confirm if I need a new transmission or its just the mechantronic hoses and sleeves. Mine only slips as the op says, when on a 20% incline. Mine is throwing a code for 5th gear incorrect ratio (P0735-07) as well as P2704-07 Transmission friction element E apply time range/performance (Mechanical failure) The video above seems to say if your getting incorrect gear ratio codes its likely the mechatronic sleeves. However the other code from my research is usually an indicator you need a new transmission or a rebuild. The car drives flawlessly expect going up mountains/steep hills in high gear and the ocassional 2-1 clunk (also video says a sign of bad mechantronic sleeves) anyone have any feedback on these codes?