Mercon SP in my 6HP26 '03 XKR
#21
08-24-2015, 02:54 PM
Hi Torrid,
As I questioned at the start of this thread, why should we be led to think that ZF built Jaguar a 6HP26 tranny made so differently from the Ford variant that it requires a magical fluid costing 3 to 5 times more? It just doesn't make sense to me. And to be honest, I feel insulted by it all. So far so good - I'm ecstatic with the results.
Keep in mind though, that the basis for my experiment is primarily: Will a properly "serviced" transmission cure most of my problems? The secondary focus was: Can MERCON be used in a properly serviced transmission without any negatives? Obviously, it's hard to split the two when done simultaneously, but I believe the answer to both is YES!
I agree: I absolutely hated that second gear "slam" especially when turning at an intersection. It was down right embarrassing.
As I questioned at the start of this thread, why should we be led to think that ZF built Jaguar a 6HP26 tranny made so differently from the Ford variant that it requires a magical fluid costing 3 to 5 times more? It just doesn't make sense to me. And to be honest, I feel insulted by it all. So far so good - I'm ecstatic with the results.
Keep in mind though, that the basis for my experiment is primarily: Will a properly "serviced" transmission cure most of my problems? The secondary focus was: Can MERCON be used in a properly serviced transmission without any negatives? Obviously, it's hard to split the two when done simultaneously, but I believe the answer to both is YES!
I agree: I absolutely hated that second gear "slam" especially when turning at an intersection. It was down right embarrassing.
#22
08-24-2015, 03:02 PM
It's all but gone ran in sport mode, but I know they probably didn't intend on sport to be always selected. A number of members have changed the fluid with the Lifeguard fluid and still had some symptoms so I know no fluid will be a fix for a failing transmission. I do need to change the fluid now being beyond 80k miles and it probably wouldn't hurt to make sure it has the latest programming and have adaptations reset at the dealer, though that procedure costs more than the Mercon!
#23
08-24-2015, 03:25 PM
Veteran Member
#24
08-24-2015, 03:33 PM
I'm reluctant to go the software update route. If the transmission shifted smoothly in the past and no other parameters have changed, updating the software could introduce new variables.
Your tranny slams into gear (it's not slipping - that's for sure), so we know the belts, clutches and torque converter are certainly able to do the job, ... "if" told to do the job properly. What about the servo-valves though? We have electronic transmissions; the TCU is still sending down what it believes to be accurate and appropriate signals. What if worn servo-valves are responding to those signals errantly?
Does anyone have any history, knowledge, anecdotes or Urban Legends on this? Can the servo-valves fail slowly; causing worsening problems over time, or do they just fail completely?
Oh just great: I've hijacked my own thread - lol.
Your tranny slams into gear (it's not slipping - that's for sure), so we know the belts, clutches and torque converter are certainly able to do the job, ... "if" told to do the job properly. What about the servo-valves though? We have electronic transmissions; the TCU is still sending down what it believes to be accurate and appropriate signals. What if worn servo-valves are responding to those signals errantly?
Does anyone have any history, knowledge, anecdotes or Urban Legends on this? Can the servo-valves fail slowly; causing worsening problems over time, or do they just fail completely?
Oh just great: I've hijacked my own thread - lol.
Last edited by scardini1; 08-25-2015 at 07:49 AM.
#26
08-24-2015, 08:42 PM
Veteran Member
Well, to be technically correct they are solenoids, not servos. By varying the drive current you can modulate how much flow goes through them.
Most solenoid valves are non linear, sometimes VERY non linear on the full scale range. One common control strategy is to try to use them in a linear range, which is usually in the middle of their open/closed cycle.
Valves can wear out, sometimes it's an electrical fault but more often it's a failure of the rubber seals in and around them, letting fluid leak past when it shouldn't. If worn seals and the resulting leakage shifts the response outside the linear range, you can get all kind of weird behavior.
One likely change of the later software updates is that it expands the range that the control system can accommodate. That would explain the software update "fix".
The other method is the Sonax kit way, which is to replace seals or in more extreme cases ream the valve body to a more consistent size and replace the metal parts and seals. Basically what a rebuild does is reduce or eliminate the leakage from worn parts or seals to get the system back into the control range the software expects.
Most solenoid valves are non linear, sometimes VERY non linear on the full scale range. One common control strategy is to try to use them in a linear range, which is usually in the middle of their open/closed cycle.
Valves can wear out, sometimes it's an electrical fault but more often it's a failure of the rubber seals in and around them, letting fluid leak past when it shouldn't. If worn seals and the resulting leakage shifts the response outside the linear range, you can get all kind of weird behavior.
One likely change of the later software updates is that it expands the range that the control system can accommodate. That would explain the software update "fix".
The other method is the Sonax kit way, which is to replace seals or in more extreme cases ream the valve body to a more consistent size and replace the metal parts and seals. Basically what a rebuild does is reduce or eliminate the leakage from worn parts or seals to get the system back into the control range the software expects.
The following users liked this post:
scardini1 (09-09-2015)
#27
09-09-2015, 12:14 PM
2 Month / 3,000 Mile Update
I just returned from a 2,000 mile cross country (172K miles on tranny now) and this is an update on the continued performance evaluation of the Mercon SP.
I am still extremely pleased with how the car is driving. Shifts through most gears are just about seamless. Of the original anomalies listed (which were just about “all” of the 6HP26’s idiosyncrasies), the only remnants are a tiny nudge when upshifting to fifth gear and a nearly imperceptible amount of surging during the morning drive in sixth gear on level ground. When I say “imperceptible” I mean that if I didn’t have a FF exhaust I wouldn’t hear it, and if I wasn’t looking for it, I wouldn’t feel or notice it at all; the surging is really THAT slight. Surging had previously been worst during winter – I’m awaiting colder temperatures to really see how much of an improvement there’s been.
I think the transmission’s “Learning Period” may have ended. Improvements to the tranny’s performance seem to have stabilized, or if they are continuing, they’re so subtle that I cannot discern differences from day to day any more.
Overall, the improvements to the transmission’s performance have beennothing short of amazing. Once againthough, I must reiterate that I cannot tell whether this is due to merely making surethe proper fluid level was established, or that the Mercon really is thatsuperior to the Redline D6 (or D4). Themain purpose of this thread is to validate the suitability of $7 per quart MerconSP versus $40 p/qt Jaguar fluid or $20 p/qt Lifeguard 6. So far, I can find absolutely no fault withthe Mercon. I will update again after I’velogged a few thousand more miles on it.
I am still extremely pleased with how the car is driving. Shifts through most gears are just about seamless. Of the original anomalies listed (which were just about “all” of the 6HP26’s idiosyncrasies), the only remnants are a tiny nudge when upshifting to fifth gear and a nearly imperceptible amount of surging during the morning drive in sixth gear on level ground. When I say “imperceptible” I mean that if I didn’t have a FF exhaust I wouldn’t hear it, and if I wasn’t looking for it, I wouldn’t feel or notice it at all; the surging is really THAT slight. Surging had previously been worst during winter – I’m awaiting colder temperatures to really see how much of an improvement there’s been.
I think the transmission’s “Learning Period” may have ended. Improvements to the tranny’s performance seem to have stabilized, or if they are continuing, they’re so subtle that I cannot discern differences from day to day any more.
Overall, the improvements to the transmission’s performance have beennothing short of amazing. Once againthough, I must reiterate that I cannot tell whether this is due to merely making surethe proper fluid level was established, or that the Mercon really is thatsuperior to the Redline D6 (or D4). Themain purpose of this thread is to validate the suitability of $7 per quart MerconSP versus $40 p/qt Jaguar fluid or $20 p/qt Lifeguard 6. So far, I can find absolutely no fault withthe Mercon. I will update again after I’velogged a few thousand more miles on it.
Last edited by scardini1; 09-09-2015 at 02:29 PM.
#29
09-09-2015, 02:20 PM
Veteran Member
As the months roll by, I think those of us who chose Mercon SP for our ZF 6HP26 units continue to strengthen the case that it is a perfectly acceptable alternative ATF. Much more reasonable in cost compared to Lifeguard 6 and our performance results are proving to be spot-on. I don't hesitate to recommend it to any owner that is out of warranty now....
#30
09-14-2015, 11:10 AM
Member
Mercon SP fluid in the ZF 5HP24??
For those of us with the older cars, would this work for the ZF 5HP24 too? Anyone tried it? ZF seems to recommend the ZF LifeguardFluid 5 for the 5HP24 and ZF LifeguardFluid 6 for the 6HP26. I can't find anywhere on the web that tells me what the difference is. Any ideas??
#32
10-01-2015, 01:55 PM
Hey guys,
I am about to tackle this project...I had and Land Rover shop did the filter and oil change for me, never did I know they use Redline...uggh! .... therefore, all the issues you mention in the original post still exists in mine.
So I think I need to grow a pair and change the fluids myself this time....before I do that, can you guys make sure I do this correctly?
1. I buy these:
Motorcraft Mercon SP Automatic Transmission Fluid ATF 12 Quarts Free Shipping | eBay
2. Drain the fluids
3. Fill it up as much as I can (till it drips)...leave the fill plug open.
4. turn on the engine ... run thru the gears
5. top off the fluid until it drips
6. use my thermo gun point it at the pan and wait until it reaches 40degree....if by that point I see drips ....I'll close the fill plug right away ...meaning I've reach the correct amount.
7. if by 40 degree I see nothing drips I top off thru the fill plug until it drips and turn off the engine....let it cool down a bit and turn it back on until I reach #6.
Does this sounds good ?please correct me if there's better way or any mistakes.
I am about to tackle this project...I had and Land Rover shop did the filter and oil change for me, never did I know they use Redline...uggh! .... therefore, all the issues you mention in the original post still exists in mine.
So I think I need to grow a pair and change the fluids myself this time....before I do that, can you guys make sure I do this correctly?
1. I buy these:
Motorcraft Mercon SP Automatic Transmission Fluid ATF 12 Quarts Free Shipping | eBay
2. Drain the fluids
3. Fill it up as much as I can (till it drips)...leave the fill plug open.
4. turn on the engine ... run thru the gears
5. top off the fluid until it drips
6. use my thermo gun point it at the pan and wait until it reaches 40degree....if by that point I see drips ....I'll close the fill plug right away ...meaning I've reach the correct amount.
7. if by 40 degree I see nothing drips I top off thru the fill plug until it drips and turn off the engine....let it cool down a bit and turn it back on until I reach #6.
Does this sounds good ?please correct me if there's better way or any mistakes.
#33
10-01-2015, 08:05 PM
Hi Z,
Before you do anything else, make sure you can get the refill plug loose (thank you Rev. Sam!). It can be VERY, VERY tight, and if after you drain the trans you "then" find out you can't free the plug, it may be time to call the tow truck.
Make sure the trans is cool "everywhere" before you start. I took readings all over the case and sump, and didn't start servicing it until temps were all down around 30 degrees C. Once the engine is started, the temperature goes up surprisingly quick and if the case is still warm, it will heat the fluid even more quickly and you'll miss your temperature window. It took HOURS for the trans to cool down sufficiently from a normal operating temperature (which is probably why the mechanics TWICE screwed-up my servicing).
BTW: 40 degrees is lower end of the target temperature range. If the fluid isn't running out by the time your sump temp hits 40, just quickly top it off and plug it before the sump hits around 48 degrees. 50 degrees is the actual maximum fluid temperature (internal), but I took a couple of degrees off that because we're measuring the outside of the sump instead.
Figure out how you're going to get the fluid up and into the transmission beforehand. I know that sounds like superfluous advice, but the truth is that getting the fluid into the trans is a bit cumbersome and can be quite messy.
Otherwise, your procedures are good. After the initial refill-start-top off- and gear cycling, I was able to add fluid and cycle through the gears twice more before the external sump temperature hit 40 degrees C and the fluid was running out of the refill port.
I know others have done the procedure with the exhaust pipes in place, and I also realize that the difficulties the exhaust pipes caused me were complicated by the fact that I have 2 1/2" pipes, but I cannot emphasize enough how much easier this procedure was with the exhaust pipe disconnected from the cat and lowered just out of the way. Have what ever gasket/seal you might need for the re-connect in hand, just in case the original one gets damaged.
The eBay deal for the fluid is good value, but seven quarts is more than enough for the job; leaving a quart or more in reserve for contingencies. And remember, because this procedure is the only way to get fluid into the transmission, having a quart (or six) on your workshop shelf really serves no purpose. If you'd rather not shell out all 90 bucks, consider that the per quart price a the Ford dealer is pretty close to the eBay deal's unit price.
I'm sorry you've had to endure the same anomalies as I did. That your shop used Redline fluid is very valuable information. I didn't specifically want to indite the Redline fluid for my problems. However, if switching to the Mercon gives you as dramatic an improvement as I've experienced, then the evidence begins to mount, at least for the use of Mercon, if not for the avoidance of Redline. You MUST report back on your driving experience afterwards!
Good luck! Don't hesitate to contact me and others directly for a little more help.
Before you do anything else, make sure you can get the refill plug loose (thank you Rev. Sam!). It can be VERY, VERY tight, and if after you drain the trans you "then" find out you can't free the plug, it may be time to call the tow truck.
Make sure the trans is cool "everywhere" before you start. I took readings all over the case and sump, and didn't start servicing it until temps were all down around 30 degrees C. Once the engine is started, the temperature goes up surprisingly quick and if the case is still warm, it will heat the fluid even more quickly and you'll miss your temperature window. It took HOURS for the trans to cool down sufficiently from a normal operating temperature (which is probably why the mechanics TWICE screwed-up my servicing).
BTW: 40 degrees is lower end of the target temperature range. If the fluid isn't running out by the time your sump temp hits 40, just quickly top it off and plug it before the sump hits around 48 degrees. 50 degrees is the actual maximum fluid temperature (internal), but I took a couple of degrees off that because we're measuring the outside of the sump instead.
Figure out how you're going to get the fluid up and into the transmission beforehand. I know that sounds like superfluous advice, but the truth is that getting the fluid into the trans is a bit cumbersome and can be quite messy.
Otherwise, your procedures are good. After the initial refill-start-top off- and gear cycling, I was able to add fluid and cycle through the gears twice more before the external sump temperature hit 40 degrees C and the fluid was running out of the refill port.
I know others have done the procedure with the exhaust pipes in place, and I also realize that the difficulties the exhaust pipes caused me were complicated by the fact that I have 2 1/2" pipes, but I cannot emphasize enough how much easier this procedure was with the exhaust pipe disconnected from the cat and lowered just out of the way. Have what ever gasket/seal you might need for the re-connect in hand, just in case the original one gets damaged.
The eBay deal for the fluid is good value, but seven quarts is more than enough for the job; leaving a quart or more in reserve for contingencies. And remember, because this procedure is the only way to get fluid into the transmission, having a quart (or six) on your workshop shelf really serves no purpose. If you'd rather not shell out all 90 bucks, consider that the per quart price a the Ford dealer is pretty close to the eBay deal's unit price.
I'm sorry you've had to endure the same anomalies as I did. That your shop used Redline fluid is very valuable information. I didn't specifically want to indite the Redline fluid for my problems. However, if switching to the Mercon gives you as dramatic an improvement as I've experienced, then the evidence begins to mount, at least for the use of Mercon, if not for the avoidance of Redline. You MUST report back on your driving experience afterwards!
Good luck! Don't hesitate to contact me and others directly for a little more help.
#34
10-01-2015, 09:59 PM
I'm really questioning messing with mine. I found out my car had a K&N filter when I went to put a new one in. I dropped in the new filter, cleaned the MAF since I had a K&N oil issue in a previous car cause a MAF code and my shift problems have completely went away. I know the fluid still needs to tended to, but with a bum hand due to tendon surgery I'm going to hold off for now.
#35
10-02-2015, 12:59 AM
Veteran Member
Here's my tips on changing the trans fluid.
https://www.jaguarforums.com/forum/x...y-tips-149505/
Also you can but the Mercon SP at any Ford dealership.
https://www.jaguarforums.com/forum/x...y-tips-149505/
Also you can but the Mercon SP at any Ford dealership.
#36
10-02-2015, 02:10 AM
Veteran Member
#37
10-02-2015, 07:02 AM
Veteran Member
Torrid,
When your hand heals up, change your ATF if you're still running the factory fill. At ten years old now, your ATF's friction modifiers are long-since shot. Fresh fluid in these ZF units is really the key in keeping them from crapping out on us....
When your hand heals up, change your ATF if you're still running the factory fill. At ten years old now, your ATF's friction modifiers are long-since shot. Fresh fluid in these ZF units is really the key in keeping them from crapping out on us....
Last edited by Jon89; 10-02-2015 at 07:05 AM.
#38
10-02-2015, 10:55 AM
Hi Z,
Before you do anything else, make sure you can get the refill plug loose (thank you Rev. Sam!). It can be VERY, VERY tight, and if after you drain the trans you "then" find out you can't free the plug, it may be time to call the tow truck.
Make sure the trans is cool "everywhere" before you start. I took readings all over the case and sump, and didn't start servicing it until temps were all down around 30 degrees C. Once the engine is started, the temperature goes up surprisingly quick and if the case is still warm, it will heat the fluid even more quickly and you'll miss your temperature window. It took HOURS for the trans to cool down sufficiently from a normal operating temperature (which is probably why the mechanics TWICE screwed-up my servicing).
BTW: 40 degrees is lower end of the target temperature range. If the fluid isn't running out by the time your sump temp hits 40, just quickly top it off and plug it before the sump hits around 48 degrees. 50 degrees is the actual maximum fluid temperature (internal), but I took a couple of degrees off that because we're measuring the outside of the sump instead.
Figure out how you're going to get the fluid up and into the transmission beforehand. I know that sounds like superfluous advice, but the truth is that getting the fluid into the trans is a bit cumbersome and can be quite messy.
Otherwise, your procedures are good. After the initial refill-start-top off- and gear cycling, I was able to add fluid and cycle through the gears twice more before the external sump temperature hit 40 degrees C and the fluid was running out of the refill port.
I know others have done the procedure with the exhaust pipes in place, and I also realize that the difficulties the exhaust pipes caused me were complicated by the fact that I have 2 1/2" pipes, but I cannot emphasize enough how much easier this procedure was with the exhaust pipe disconnected from the cat and lowered just out of the way. Have what ever gasket/seal you might need for the re-connect in hand, just in case the original one gets damaged.
The eBay deal for the fluid is good value, but seven quarts is more than enough for the job; leaving a quart or more in reserve for contingencies. And remember, because this procedure is the only way to get fluid into the transmission, having a quart (or six) on your workshop shelf really serves no purpose. If you'd rather not shell out all 90 bucks, consider that the per quart price a the Ford dealer is pretty close to the eBay deal's unit price.
I'm sorry you've had to endure the same anomalies as I did. That your shop used Redline fluid is very valuable information. I didn't specifically want to indite the Redline fluid for my problems. However, if switching to the Mercon gives you as dramatic an improvement as I've experienced, then the evidence begins to mount, at least for the use of Mercon, if not for the avoidance of Redline. You MUST report back on your driving experience afterwards!
Good luck! Don't hesitate to contact me and others directly for a little more help.
Before you do anything else, make sure you can get the refill plug loose (thank you Rev. Sam!). It can be VERY, VERY tight, and if after you drain the trans you "then" find out you can't free the plug, it may be time to call the tow truck.
Make sure the trans is cool "everywhere" before you start. I took readings all over the case and sump, and didn't start servicing it until temps were all down around 30 degrees C. Once the engine is started, the temperature goes up surprisingly quick and if the case is still warm, it will heat the fluid even more quickly and you'll miss your temperature window. It took HOURS for the trans to cool down sufficiently from a normal operating temperature (which is probably why the mechanics TWICE screwed-up my servicing).
BTW: 40 degrees is lower end of the target temperature range. If the fluid isn't running out by the time your sump temp hits 40, just quickly top it off and plug it before the sump hits around 48 degrees. 50 degrees is the actual maximum fluid temperature (internal), but I took a couple of degrees off that because we're measuring the outside of the sump instead.
Figure out how you're going to get the fluid up and into the transmission beforehand. I know that sounds like superfluous advice, but the truth is that getting the fluid into the trans is a bit cumbersome and can be quite messy.
Otherwise, your procedures are good. After the initial refill-start-top off- and gear cycling, I was able to add fluid and cycle through the gears twice more before the external sump temperature hit 40 degrees C and the fluid was running out of the refill port.
I know others have done the procedure with the exhaust pipes in place, and I also realize that the difficulties the exhaust pipes caused me were complicated by the fact that I have 2 1/2" pipes, but I cannot emphasize enough how much easier this procedure was with the exhaust pipe disconnected from the cat and lowered just out of the way. Have what ever gasket/seal you might need for the re-connect in hand, just in case the original one gets damaged.
The eBay deal for the fluid is good value, but seven quarts is more than enough for the job; leaving a quart or more in reserve for contingencies. And remember, because this procedure is the only way to get fluid into the transmission, having a quart (or six) on your workshop shelf really serves no purpose. If you'd rather not shell out all 90 bucks, consider that the per quart price a the Ford dealer is pretty close to the eBay deal's unit price.
I'm sorry you've had to endure the same anomalies as I did. That your shop used Redline fluid is very valuable information. I didn't specifically want to indite the Redline fluid for my problems. However, if switching to the Mercon gives you as dramatic an improvement as I've experienced, then the evidence begins to mount, at least for the use of Mercon, if not for the avoidance of Redline. You MUST report back on your driving experience afterwards!
Good luck! Don't hesitate to contact me and others directly for a little more help.
#39
10-02-2015, 11:06 AM
Here's my tips on changing the trans fluid.
https://www.jaguarforums.com/forum/x...y-tips-149505/
Also you can but the Mercon SP at any Ford dealership.
https://www.jaguarforums.com/forum/x...y-tips-149505/
Also you can but the Mercon SP at any Ford dealership.
The following users liked this post:
Jandreu (10-02-2015)
#40
10-16-2015, 09:23 AM
5,000 mile update on switching to Mercon SP:
Well, … not much to say, and that’s a really good thing. It’s been 5,000 miles and 3 months since switching to Mercon from Redline. The transmission is still shifting very well and much better than previously. There is still a little nudge when up-shifting to 5th (which I suspect is a unique characteristic of just my transmission), and as expected, the minor surging that many of us experience in the morning is a little more noticeable with cooler weather setting in.
I am still VERY happy with the switch to Mercon and plan on doing another fluid replacement in the future to increase the percentage of Mercon in the system. I suspect that with just a routine drain & refill we only replace about 60% to 70% of all the fluid, so another refill will approach a complete flush.
I am still VERY happy with the switch to Mercon and plan on doing another fluid replacement in the future to increase the percentage of Mercon in the system. I suspect that with just a routine drain & refill we only replace about 60% to 70% of all the fluid, so another refill will approach a complete flush.