Confusing Transmission Issue
#1
11-11-2019, 08:56 PM
Confusing Transmission Issue
Hey everyone,
I recently purchased an 05 LR3 4.4 with 296k miles on it (I know the mileage is super high, but for my purposes it is perfect).
The transmission has a weird bump when starting from a quick stop and throws a tq converter solenoid code.
What is unusual to me is that when driving at freeway speeds, it does not shift past 4th gear unless in manual mode. When driving on the freeway in “D” it will alert me to a trans fault, but will still manually shift through all of the gears.
i am familiar with the Zf6hp26 transmission, as I have a 2012 RR and recently sold an 06 RR, but when the transmission went on my 06, the transmission faults would lock me into 3rd or 4th until a restart.
I’ve searched several posts and read a variety of possible causes. I’m fine with replacing the transmission, but it seems like more of a sensor issue to me based off of the fact the the transmission will still shift and is not slipping.
it almost seems like the transmission is being told that I’m still accelerating.
anyone have a similar issue? How did you ultimately fix it?
thanks for your input!
I recently purchased an 05 LR3 4.4 with 296k miles on it (I know the mileage is super high, but for my purposes it is perfect).
The transmission has a weird bump when starting from a quick stop and throws a tq converter solenoid code.
What is unusual to me is that when driving at freeway speeds, it does not shift past 4th gear unless in manual mode. When driving on the freeway in “D” it will alert me to a trans fault, but will still manually shift through all of the gears.
i am familiar with the Zf6hp26 transmission, as I have a 2012 RR and recently sold an 06 RR, but when the transmission went on my 06, the transmission faults would lock me into 3rd or 4th until a restart.
I’ve searched several posts and read a variety of possible causes. I’m fine with replacing the transmission, but it seems like more of a sensor issue to me based off of the fact the the transmission will still shift and is not slipping.
it almost seems like the transmission is being told that I’m still accelerating.
anyone have a similar issue? How did you ultimately fix it?
thanks for your input!
#2
11-11-2019, 10:35 PM
From what I have gathered, IF it shifts in all gears, it is frequently the solenoids and less common torque converter. They can be had for a few hundred on line when you do the bmw metal trans pan and filter conversion. I'm still not sure what fluid to use though. I had almost the same problem with a Jag -- same trans. on that one, it was just a matter of replacing the fluid and filter - it was low. I used Mobil 1 synthetic and no problems in past 10k miles.
My daughters LR3 has some odd trans issues I am trying to sort now
My daughters LR3 has some odd trans issues I am trying to sort now
#3
11-11-2019, 10:53 PM
Thanks for the input! I actually have a full set of spare solenoids from my L322, I’m just hesitant to swap them because of the age of the transmission. The solenoids will be my last ditch effort before throwing a new transmission at it.
I just Checked live values via obd2 for my TPS vs APS and got some interesting results as well that I’m going to look into.
I just Checked live values via obd2 for my TPS vs APS and got some interesting results as well that I’m going to look into.
From what I have gathered, IF it shifts in all gears, it is frequently the solenoids and less common torque converter. They can be had for a few hundred on line when you do the bmw metal trans pan and filter conversion. I'm still not sure what fluid to use though. I had almost the same problem with a Jag -- same trans. on that one, it was just a matter of replacing the fluid and filter - it was low. I used Mobil 1 synthetic and no problems in past 10k miles.
My daughters LR3 has some odd trans issues I am trying to sort now
My daughters LR3 has some odd trans issues I am trying to sort now
#4
11-11-2019, 11:35 PM
For any of the 6 speed Jag powered petrol Rovers either Lifeguard 6 or Ford Mercon SP can be used. The SP is chemically identical to the LG6 fluid outside of colour, it is used in the Ford/Lincoln products with your transmission. I've personally been using it in all of the 6HP trucks I buy.
LG6 is an average of $20 a quart vs I paid $6 a quart for SP at my local Ford/Lincoln dealership.
It'd be a good idea to replace the tube seals and the bridge seal in between the mechatronic unit and the rest of the transmission.
LG6 is an average of $20 a quart vs I paid $6 a quart for SP at my local Ford/Lincoln dealership.
It'd be a good idea to replace the tube seals and the bridge seal in between the mechatronic unit and the rest of the transmission.
#5
11-12-2019, 12:39 AM
pentosin also makes a lifeguard fluid that’s currently on sale for about 14 at my local auto parts store. I used Mercon SP on my 06 RR when I replaced the solenoids in it.
Still hesitant to replace anything on my transmission due to the high mileage though.
Still hesitant to replace anything on my transmission due to the high mileage though.
For any of the 6 speed Jag powered petrol Rovers either Lifeguard 6 or Ford Mercon SP can be used. The SP is chemically identical to the LG6 fluid outside of colour, it is used in the Ford/Lincoln products with your transmission. I've personally been using it in all of the 6HP trucks I buy.
LG6 is an average of $20 a quart vs I paid $6 a quart for SP at my local Ford/Lincoln dealership.
It'd be a good idea to replace the tube seals and the bridge seal in between the mechatronic unit and the rest of the transmission.
LG6 is an average of $20 a quart vs I paid $6 a quart for SP at my local Ford/Lincoln dealership.
It'd be a good idea to replace the tube seals and the bridge seal in between the mechatronic unit and the rest of the transmission.
#6
11-12-2019, 05:55 AM
Winching
There are two types of "solenoid" codes, so you have to be careful. A "solenoid circuit" code is pretty self explanatory. Since the TCM is inside the transmission, there are no wires to worry about. The solenoid plugs directly into the TCM, so its one or the other and 99.9% of the time, its NOT the TCM, so solenoids fix it.
The other type of fault is a "solenoid performance" and that you have to watch out for. It means the solenoid was commanded but nothing happened. It still could be a solenoid fault, but it also could be a jammed/sticking/worn valve in the valvebody itself. Very rare is it a clutch issue because those set Gear Ratio codes. For a "performance" code, I would do a complete valvebody (Mechatronics) instead of just solenoids.
As for the not upshifting, usually we see this with mismatched tire sizes (i.e. 3 tires will be a 255/45/19 and one will be a 255/40/19) and that puts the trans in "cornering mode" and inhibits high gear upshifts. However, since you physically have a fault stored, I would start there first. Gears are limited based on what code is stored.
The other type of fault is a "solenoid performance" and that you have to watch out for. It means the solenoid was commanded but nothing happened. It still could be a solenoid fault, but it also could be a jammed/sticking/worn valve in the valvebody itself. Very rare is it a clutch issue because those set Gear Ratio codes. For a "performance" code, I would do a complete valvebody (Mechatronics) instead of just solenoids.
As for the not upshifting, usually we see this with mismatched tire sizes (i.e. 3 tires will be a 255/45/19 and one will be a 255/40/19) and that puts the trans in "cornering mode" and inhibits high gear upshifts. However, since you physically have a fault stored, I would start there first. Gears are limited based on what code is stored.
#7
11-12-2019, 08:55 AM
The code is P0741 - Torque converter clutch solenoid - circuit performance or stuck off.
i JUST ordered new solenoids last night. Perhaps I need to cancel that order and look for the whole mechatronic unit.
i JUST ordered new solenoids last night. Perhaps I need to cancel that order and look for the whole mechatronic unit.
There are two types of "solenoid" codes, so you have to be careful. A "solenoid circuit" code is pretty self explanatory. Since the TCM is inside the transmission, there are no wires to worry about. The solenoid plugs directly into the TCM, so its one or the other and 99.9% of the time, its NOT the TCM, so solenoids fix it.
The other type of fault is a "solenoid performance" and that you have to watch out for. It means the solenoid was commanded but nothing happened. It still could be a solenoid fault, but it also could be a jammed/sticking/worn valve in the valvebody itself. Very rare is it a clutch issue because those set Gear Ratio codes. For a "performance" code, I would do a complete valvebody (Mechatronics) instead of just solenoids.
As for the not upshifting, usually we see this with mismatched tire sizes (i.e. 3 tires will be a 255/45/19 and one will be a 255/40/19) and that puts the trans in "cornering mode" and inhibits high gear upshifts. However, since you physically have a fault stored, I would start there first. Gears are limited based on what code is stored.
The other type of fault is a "solenoid performance" and that you have to watch out for. It means the solenoid was commanded but nothing happened. It still could be a solenoid fault, but it also could be a jammed/sticking/worn valve in the valvebody itself. Very rare is it a clutch issue because those set Gear Ratio codes. For a "performance" code, I would do a complete valvebody (Mechatronics) instead of just solenoids.
As for the not upshifting, usually we see this with mismatched tire sizes (i.e. 3 tires will be a 255/45/19 and one will be a 255/40/19) and that puts the trans in "cornering mode" and inhibits high gear upshifts. However, since you physically have a fault stored, I would start there first. Gears are limited based on what code is stored.
#8
11-13-2019, 06:41 PM
Winching
Hard to say with that code if its a solenoid or not, but in my experience, TCC codes are usually the converter, not the solenoid.
If you want to know if its a Solenoid without buying a new one, you can drop the Mechatronics and swap the solenoids. TCC is controlled by EDS #6, its a yellow solenoid on the end next to a black solenoid. Swap it with another yellow Solenoid and see if the same fault occurs, or if it turns into a Gear Monitoring code.
If you want to know if its a Solenoid without buying a new one, you can drop the Mechatronics and swap the solenoids. TCC is controlled by EDS #6, its a yellow solenoid on the end next to a black solenoid. Swap it with another yellow Solenoid and see if the same fault occurs, or if it turns into a Gear Monitoring code.
#9
11-13-2019, 06:54 PM
I have some spares sitting around that I will toss in there. My only huge concern is changing the fluid at that mileage... any specific friction modifiers you would recommend adding to reduce the possible problems with new fluid?
Hard to say with that code if its a solenoid or not, but in my experience, TCC codes are usually the converter, not the solenoid.
If you want to know if its a Solenoid without buying a new one, you can drop the Mechatronics and swap the solenoids. TCC is controlled by EDS #6, its a yellow solenoid on the end next to a black solenoid. Swap it with another yellow Solenoid and see if the same fault occurs, or if it turns into a Gear Monitoring code.
If you want to know if its a Solenoid without buying a new one, you can drop the Mechatronics and swap the solenoids. TCC is controlled by EDS #6, its a yellow solenoid on the end next to a black solenoid. Swap it with another yellow Solenoid and see if the same fault occurs, or if it turns into a Gear Monitoring code.
#10
11-16-2019, 10:45 PM
UPDATE:
I just finished installing a new transmission filter/pan (lucky8), new transmission fluid (liqui-moly), new valve body seals, adapter seal block, mechatronic plug seal, and solenoids (100k mile solenoids I had laying around. Cleaned with MAF cleaner and new o-rings. Resistance tested to ensure they were in spec).
Took it out for a drive and the bump when starting/stopping is gone. There was a slightly harsh 2/3 shift, but after resetting the adaptations and driving around very carefully I am happy to report that the issue is resolved!
I just finished installing a new transmission filter/pan (lucky8), new transmission fluid (liqui-moly), new valve body seals, adapter seal block, mechatronic plug seal, and solenoids (100k mile solenoids I had laying around. Cleaned with MAF cleaner and new o-rings. Resistance tested to ensure they were in spec).
Took it out for a drive and the bump when starting/stopping is gone. There was a slightly harsh 2/3 shift, but after resetting the adaptations and driving around very carefully I am happy to report that the issue is resolved!
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