In researching the trans servicing I have found my very well respected ind. shop uses Mercon in all his Jag work. He also feels the drain plug will most likely crack or leak if trying to do fluid only with pan on. My XJ8 w/ 85K has a slow/ late downshift into 1st at a stop & a shudder in 5th to 6th at slight acceleration, yet quiet & shifts fine otherwise. Any thoughts?

 

Belsy -- I say this with all due respect: "Your very well respected indie shop may rate just a touch less respect".

With your mileage you should do a pan off filter and fluid exchange as recommended, even if the reasoning is largely flawed .

As for the fluid, I would go with the Mobile1 ATF or the Jag recommended stuff because we have a track record with those fluids from trusted sources here on the Forum. I don't recall any Mercon testimonials/recommendations from any source for the 350 series cars.

Were I you, I would insist on the Mobil 1 ATF.

We have a well respected Jag shop near my town who told me that he did not do transmission refills using the temp. measurement method as it was unnecessarily complicated. Since then he has not been near my car. Proceed with caution. Whereabouts in Fl are you?

 

Tarheel,

I am in Debary / Sanford area & you may know the shop I refer to in Longwood.
I was under my car yesterday and could not find the re-fill plug?? I was thinking about the fluid only change to see how bad fluid looked and moniter any improvement.


Belsy

 

Belsy,

The shop I like in our area is AllJag. They are near to you, they know their stuff and they will install the Mobil 1 ATF together with the correct filter. They prefer to use an OEM Jag filter but they will use an after mkt one supplied by you if you desire.

Another reason I like these guys is that they have made the investment in all necessary software to service the 350 series Jags. Also, they will do a fluid only flush/exchange and they know how to top it off using the temp measurement method.

P.S. the drain plug is on the right side on the xmission case.

 

I know AllJag & they were not comfortable doing a flush & exchange as they felt the drain plug would either crack or leak. They also mentioned Mercon, so who knows maybe they have changed position on this area??

Either way I will use them as they are good guys and care for the Jaguar line!!

 

Well I don't know what to think. I guess I'm a pretty opinionated guy who tells folks exactly what I want and asks what it's going to coast. I brought them 12 qts of Mobil 1 ATF, told them to flush out the xmission twice and top it off the 3rd time at the correct temp. They said "yes sir" and had me on the road in 2 hours for $80. I did not change the filter as I was only at 50K miles. Don't hold me to that price, it was a year ago.

There was no BS about Mercon and broken fill plugs. What nonsense!

Now on the other hand,if you have no strong opinions on the subject one way or another don't be afraid to go with AllJags program. For sure you need a new filter at 80K + miles. I do rely on them in areas where I have no knowledge. I've had 6 Jags in 40 years and up until recent years done my own work. I'm still able to learn a thing or 2 - but not much.

BTW- if they have changed hands in the last year get back to us PDQ.

 

ZF 6HP26's should get Lifeguard 6 fluid to be sure of a long life. ZF says that there are no other fluids that meet this spec. It seems to me that if one is changing fluid to save the transmission a rebuild, one would put the right fluid in it or just forget it. The ZF fluid is $17 and that is pretty pricey, but since other high end synthetic fluids run $8-10 per qt, and it only takes 6 quarts, the difference of about $50 seems so insignificant as to be odd. If one waits for 60K or so, they would have already changed a conventional tranny at least once, so they are saving some money on fluid anyway. This scrapping for cheap alternate fluids should be over now that CTSC has everything at reasonable prices. I understood it back when Jag was gouging it customers for the stuff, but the time has passed. The value of a forum is to make others aware of new developments and this is it.

 

I agree with that, unless someone has determined that Mobil1 is the same formulation as Lifeguard. In another thread someone said that the dealership only used Shell.

Anyhow, ZF says it takes 10.5 quarts, not 6.

 

Well now we all have something to agree to disagree about.

Seems the ZF is so fragile and depends on hi maintenance & material to arrive where so many others go into the 150k mile area for 1/4 the cost! Yet we stay loyal to these brands and swear by their performance while they seem to appear in many more vehicles?

If other fluids are being tested and driven why not wait out some follow up stories & results? Performance is the best reference vs. brand recognition.

As far as our friends in C.Fl. they are still the same owners and I will remind them of the basic flush & change, but I thought it took several hours to drain so how did you get done in 2 hours??

Again thanks to all for the replies and I will post my details & results.

 

Just received a response from ZF. Read it here:

https://www.jaguarforums.com/forum/j...46/#post358569

 

I have no proof, but all the signs point to marketing and competition for trouble free cars as the reason for the lifetime fill. Engineering lost out.... so the poor guys that get these cars second hand after a few years have to deal with the reality that these trannys have friction clutches that dirty up the fluid just like any other and it needs changing at about 60K of you want it to be reliable. I don't like it but it's just reality staring us in the face. My XKR has 46K on it and I will change it now too, just due to the type of driving it gets as opposed to the sedan.

 

The Mercon for the 6sp is a rebranded ZF lifeguard6 fluid just as the Jag fluid is – so that is the only way I would go if I should go another route –but I don’t think Mercon 6sp is less than what you now can get lifeguard6 for(17$)? What I have asked the shop to do is drop the pan, replace pan/filter and fill up to spec, and do a trans flush afterwards. That is the only way to get all old fluid replaced without wasting excess fluid. I did the above procedure at 52k but with redline D4 fluid which the indy shop I used at that time as well as another site on the net and Redline themselves recommended as excellent replacement. I did compare the spec. for the fluids at that time, which is why I know about Mercon, but Mercon was still expensive – remember 27$ (did at that time not have access to lifeguard6 for 17$) and the spec for the D4 was very close (closer than Mobil) – and D4 it was. I was not satisfied with the D4 fluid at all – the trans shifted up earlier than usual and had a late shift into 1st at stops – was reluctant/slow to shift down when accelerator was pushed even floored sometimes (otherwise the trans worked well). My fluid was replaced at 59k with the above procedures but this time with Lifeguard 6 – the trans was/is like new –shifts/downshift are again just perfect – like it was prior to the change at 52k! For the record when my lifeguard was replaced at 52k it was in very good condition still smelled like new fluid and the fluid was completely clear –very good fluid.
I am not saying that Mobil (the Redline worked just not as good as lifeguard) does not work but for 17$ for the lifeguard I would not use anything else than that.

 

For those using Mobil 1, ExxonMobil states that their fluid does not meet the requirements of ZF transmissions.

 

The refill amount is a moving target. The dry tranny holds 10.5 quarts, but the torque converter holds a little more than 2 qts and does not drain out as well as some of the valve body parts and other components. If the pan is replaced and allowed to drain for some time, I understand the refill can take about 7.5 qts. If the pan is not replaced, the refill is more like 5 qts. I have noted than when removing the filter, quite a bit of fluid is released out of the filter suction opening. I prefer to change as much as possible, so I change the filters each time and let it sit for a couple hours with the pan open.

 

Belsy,

I know you got lost in the shuffle of the big ATF debate but don't neglect to let us know what you decide and how it turns out.

I have an idea that a filter and new ATF fluid will solve your problem.