Checked with Lincoln dealer & Land Rover since they service 6HP26 transmissions in their vehicles. They both use flush machines that utilize the cooler lines and do a double flush. The price is only $199 including ZF approved fluid.

Is this a proper service and will it completely clean out the transmission of old fluid? Any reason to drop the pan and and fill that way?

Thank you!

 

Good thinking! Looking forward to an answer from a Pro. Of course this does mean that the filter will not be replaced... do we need a mod with an inline filter?

 

From what I can tell with the bit of research I have done it is unlikely at under 100K miles the filter needs to be replaced with the first fluid change. Take a look at what Rover owners are saying about their ZF fluid. I have yet to see anyone from BMW, Audi and others have anything to say about sludge and severely poor quality fluid even with first changes at 100K miles. ZF specified a very high quality fluid. Not that it would hurt to go through the trouble and expense of installing a new pan, the experts seem to think it unnecessary until the second or third fluid change.

Since Ford/Lincoln and Rover seem to think a flush via the cooler line is the best, quickest, least invasive, least costly and most thorough fluid replacement, then why not?

I would still like to hear from some Jaguar techs with their thoughts.

 

There's also the fact that the majority of the fluid is in the torque converter which won't be changed by replacing the pan.

 

All of the DIY threads I have read here and elsewhere have indicated around 7 quarts via the drain method, however the dealer said there is about 12 quarts in the system and they use 24 quarts.

Still would like to know if this removes ALL old fluid and if it is safe. I have continued to check other manufacturer's factory procedures for ZF flushes and they all do it through the cooler line.

 

ZF fluid it approx. 17/gal - check this is lifeguard6 they are using - I doubt it. I have had a drain and a flush performed - there should be info on this forum. I would only use ZF lifeguard 6 fluid - tried redline d4 which is approved - did not work satisfactory - price difference is not great.

 

They are using Mercon SP which according to the Ford/Lincoln service manual for the 6HP26 is the correct replacement fluid. But the service manual also describes the drain and fill procedure exactly the same way others here have done it which is to drop the pan and refill with 5 quarts of SP between 30-50 C until it spills from the fill hole and cycle through the gears and replace with a new pan.

So......

 

Mercon SP is lifeguard 6 fluid just renamed for Ford - It was not any cheaper when I checked prices some time back - it most be cheaper now!

 

This is without a doubt the best and most thorough method of cleansing the box of all old oil

I have this method performed on my X308 every three years.
Considering the mileage I do, I have the sump dropped and filter changed and magnets cleansed every second oil change.

These transmissions hold around 10 litres in total.

With your box at such a low mileage you wouldn't have to worry about a filter change first time around.

On the ZF 6HP26 boxes it pays to stick to the genuine Lifeguard-6 fluid even if it's a litte expemsive.

Be rest assured, the flushing machine approach is the best and most effective method of servicing these boxes properly.

Ther are too many people out there who still think modern boxes can be serviced like they were 20 years ago.....technology has moved on ;o))

 

I admit that I don't know much about ZF6HP26 transmissions, but I am familiar with GM transmissions. A 700R4/4L60 holds around 11 quarts total, distributed like this:

6 quarts in the transmission, including 1 quart in the front valve body and pump that won't be drained by dropping the pan.
2 quarts in the torque converter.
3 quarts in the transmission cooler that also won't be drained by dropping the pan. Some applications hold more than that depending on the size of the cooler.

So out of the 11 quarts total, only 5 will be changed by dropping the pan. I would imagine the ZF trans is similar, which would be why the amount of fluid seems to vary from 6-17 quarts. How does changing less than half the fluid help?

 

This my friend is where missinformation gets a hold and becomes gospel ;o))

The 'drop the pan' method has to be performed at least three times to remove all the old oil which has ben diluted with fresh oil.....innefective, lazy and a waste of expensive fluid.

Get it done correctly the first time....there are no short cuts with these transmissions.....not unless you are a fan of paying expensive rebuild/replacement bills....your call ;o]

 

Well, after being told over the phone by both Lincoln and Ford dealers they could do the 24 quart flush, in person their respective techs declined to attempt the procedure.

However, this morning while getting my new tires balanced at Jaguar, I found out they have just starting doing cooler line transmission flushes, same as other dealers, using ZF branded fluid for only $300, considerably less than what others have posted on other threads.

So the conclusion is save yourself a bunch of money and time and have it done correctly.

Dropping the pan, installing a new pan, etc appears to be a huge waste of money and does little for the transmission.

 

One good reason to drop the pan is that the pans not only develop leaks but so do the Motronics sleeves, which require a pan drop to replace since they have a lock on the inside of the tranny. Since the filter is in them too, there are three good reasons to replace the pans. I would not want to go to all the trouble of replacing all the fluid just to leave a dirty filter for it all to run through. If you see the black fluid after about 60-70K, you will not want your new fluid to contact a dirty filter.

 

What a flush is doing is that it replaces the fluid that is send to the cooler as it is running. Dont think this replaces all the fluid it doesnt. As the pump circulates the fluid it sends from the pan/filter into the internal and some out to the cooler. The part that goes into the internal of the transmission will go down in the pan so you will get a mixs - typ. the shop will shop the mashine when fluid looks clean - maybe after 7qts some will say 12qts put you will still have a mix - maybe at 3 times the fluid capacity flush you will have 95% replaced.

 

This is a good point, using the cooler lines does not negate the need to do a level check. The cooler in and out volume is not regulated or balanced (it doesn't need to be to function normally) so you don't know if the tranny is over or underfilled when you are done. Be careful using this method, be sure to run the level check afterwards. It will replace all th efluid though, but as was stated, the pump sucks fluid out of the pan and pumps it into the various works of the tranny, some of which just drops right back into the pan, so it mixes with the gluck again. Not the clean change that you envision. I am comfortable with the usual drain and refill system, the mix ends up about the same for the given amount of fluid used.

 

Oh boy, another debate

Jag dealer, like other dealers mentioned here, said this is the most thorough flush. Twelve quarts are flushed through the system, then another 12 quarts are flushed through with the motor running and run through all gears.

 

The transmission fluid change machine will supposedly send an equal amount of fluid in as it receives - so check of level should not be necessary - though Jag can read it from the computer if needed.
How is 12 qt being flush through without the transmission pump running hence the engine running - am I misunderstanding something? - 24qt of ZF lifeguard would be more than 300$ -just saying.
Most of the gunk will be in the pan and screen - the flush will not get that out - I combined both methods when I did it - first got pan replaced and then a flush (that does not replace all the fluid either just some more) - If I should choose one over the other my focus would be to get gunk out - just my opinion. BTW when the fluid was replaced at 50k it smelled and looked almost like new which indicates that the ZF fluid is a very good fluid.

 

From what I have read on other forums, it is doubtful a low mileage transmission will be full of gunk. I will side with the ZF experts and change the filter at 130-150K miles.

The Jag dealer buys the fluid in bulk 55 gallon drums. I bet they pay not much more than $100 for the 24qts. It is on them if they don't do it correctly.

 

So I have not driven the car very much for the past couple of months and finally got around to the Jag dealer for a transmission flush. Before the procedure was performed I wanted to confirm they would use Jaguar or ZF fluid...guess what? Turns out they do not, they claim to use something significantly superior to factory fluid, BG and if you read their hype, BG would seem like the holy grail for transmission fluids. However I opted to decline the service unless it would use factory fluid.

Well, crap! I am no chemical engineer, all I can go with is what people say...ZF and may others insist there is no substitute for their fluid and I have no doubt it is formulated correctly for the design of their transmission so I guess it is back to the Ford dealer for a MERCON SP flush for less money....

 

I ran Mobil 1 Synthetic ATF in my 05 XJR for 2 years. Shift quality over the used up OEM fluid improved and no down side I'm aware of.

Cooling line auto flush technique/machine is out for these ZF transmissions as the amount and temp. of fluid required is quite precise, neither of which can be addressed by the auto flush machines.

This topic was addressed 2 years back. I don't think anything has changed. I could be wrong--- Nah!