Glad to hear it - stay healthy Glenn

 

Brother I feel your pain. Its been a rabbit hole i went down and to be honest I'm no better informed than when I started. All I'm certain of is nobody has a conclusive and final answer we can bank on.

Your techs input raised a question for me as to who makes the "official" jaguar fluid?? I'd decided it'd be smart to use the manufacturers fluid for the transmission so ZF Lifeguard was what I thought would be the end result. I'm thrilled to find that my journey to the end of the world isn't over.

I'll watch this thread forever. Its sure to be full of thoughts and theories. Maybe someone has tapped into a new tranny, pulled a sample and had it analyzed? Doubt it but it looks like the only way to know for sure. We may need a community project and all pitch in to find the truth. This is as bad as getting a straight answer from a lawyer or the truth from the government. Wow.

Rich

 

I haven't read the thread as it's rather old now but if you want to be 100% safe with your X150 gearbox just use the appropriate ZF Lifeguard fluid as there is nothing special about the ZF boxes used in the X150. You can use one of the cheaper equivalent fluids and many people do without any problems, but for the extra marginal cost I have always settled for the ZF version.

Richard

 

I waited till about 115k miles before doing my first tranny service. Used LG6. no difference in performance and there really wasn't an issue to begin with. I ordered the kit with the tray and LG6. When I called up Erickson they needed my vin and sent me the kit out. So there ya have it.

R4

 

Technically Shell made the fluid and sold it to Jaguar and ZF. If you drill down the service manual it actually says to use Shell M-1375.4 semi-synthetic transmission fluid.

I've been running Amsoil fuel efficient 100% synthetic transmission fluid for the last 5 years and it was a big difference compared to the OEM fluid. I use to get a slight thump when changing from 3rd to 2nd with enthusiastic throttle with the OEM fluid. However with Amsoil transmission fluid the auto so smooth I don't even know if it ever change gear.

Amsoil fuel efficient trans fluid meet and exceeds the Shell M-1375.4 fluid specifications specially flash point and cold temperature pour point and very sheer stable under extreme conditions.

I wanted a fluid that can handle the punishment and heat of the way I drive without the fluid breaking down and leaving me with an expensive repair bill.

 

Can you please share the part numbers for the kit?

 

Since members are finding this old thread in search of information on correct fluids for the ZF 6HP26 six-speed automatic transmission, here's what we know:

ZF specifies its own Lifeguard 6 fluid, meeting Shell specification M1375.4. The Jaguar fluid was just re-branded Lifeguard 6. Through the research of forum members including Partick the Cat, Box, myself and others, along with a Blackstone Labs analysis by bimmerfest member fun2drive, we know that aside from color, Ford Motorcraft Mercon SP and Shell Spirax S4 ATF MSP are identical to Lifeguard 6. Lifeguard 6 and Spirax S4 are manufactured by Royal Dutch Shell, and Mercon SP is manufactured by Shell U.S.A. Ford licensed the 6HP for use in some of its vehicles, for which it specifies Mercon SP.

Many third-party fluid makers claim that one or more of their fluids meets Shell M1375.4, yet the fluid's published physical characteristics are significantly different from those of Lifeguard 6. For example, Pentosin ATF 1 is claimed to meet Shell M1375.4, yet its kinematic viscosity at 40 degrees Fahrenheit (KV40) is 38.0 mm2/s, compared to 26.8 mm2/s for Lifeguard 6. Another example is Valvoline MaxLife Multi-Vehicle ATF, which is claimed to meet M1375.4 and to be equivalent to Mercon SP, Mercon LV, and ZF Lifeguard 8. Yet ZF clearly deliniates between transmissions that require Lifeguard 6 and Lifeguard 8, with no overlap, and Ford specifically states that Mercon SP must never be used in a vehicle for which Mercon LV is specified, and vice versa. Valvoline must compromise the fluid formulation so it is "good enough" to function in all of these diverse transmissions, but we must wonder if these compromises lead to sub-optimal performance. We simply cannot trust the claims of third-party fluid makers without doing our due diligence.

The KV40 of Amsoil Signature Series Fuel-Efficient Synthetic ATF is 30.8 mm2/s, or 15% more viscous (thicker) than Lifeguard 6. This might change the behavior of the transmission, and especially the torque converter, and the change might be sensed by the driver as positive. But using a thicker fluid could lead to elevated internal pressures and temperatures, premature failure of the torque converter or fluid pump, insufficient fluid flow at low temperatures, and that is just considering the thicker viscosity. We have no idea if the additive package meets the various requirements of the 6HP.

The KV40 of BG Premium Full Synthetic ATF is 34.28 mm2/s, or 28% more viscous than Lifeguard 6. Imagine the added strain that would add to the 6HP torque converter and pump over time....

The transmission is the second-most expensive component in the vehicle. Since transmission fluid-related failures tend to take tens of thousands of miles to manifest, why risk using a fluid not approved by ZF?

Cheers,

Don

 

Again Don. Excellent post with numbers to back it up. You never force your opinion just put out the info. Well done. I for one appreciate it. On my first fluid change i know it was the valvoline because the previous owner gave me the invoice. I replaced with pentosin before finding your info. Then replaced with merconsp then had a 3 year trans issue that had me replacing fluid again about 3 times with merconsp. Last year i finally resolved the issue but ford has discontinued merconsp as a dealership stocked item and the price went up quite a bit. The parts man said once the central supply houses run out it is gone. Tried to tell me merconlv was the direct replacement. I opted for lifegard6 to make sure i got it right as i never expect to change the fluid again under my watch. Trans is like new. Thanks again

 

I focus on the kinematic viscosity at 100°C because it reflects how the fluid performs under high operating temperatures, particularly in terms of oxidation resistance and thermal stability under heat stress. While the KV40 value is important for extremely cold starts, it's less relevant to me since we don't experience snow in winter, and temperatures rarely drop below 5°C in the winter mornings. On the other hand, we often hit 45°C during summer, when most of my driving happens. Sitting in bumper to bumper summer traffic where there is no airflow and the road surface is over 65+degC and radiating heat on critical components.

With mechanical sympathy in mind, I prefer to let everything reach operating temperature before giving it the beans.

 

When ZF introduced the 6HP in 2000 as the first six-speed automatic transmission for passenger cars, it touted the very fine tolerances required to fit six forward gears into a package smaller than the previous 5-speed 5HP. At the same time, ZF introduced a new, very low-viscosity fluid, Lifeguard 6. The technical documentation mentioned the importance of the fluid flowing properly at low temperatures. "Low temperatures" presumably means temperatures lower than 40°C / 104°F, which is obviously not "cold" in human terms. But it is reasonable to think that, globally, most "cold starts" occur at ambient temperatures below 40°C / 104°F, the lower temperature at which transmission fluid viscosity is commonly measured, and a temperature at which Amsoil is significantly thicker than Lifeguard 6.

I have flushed the fluid in a lot of 6HP transmissions (in Jaguars, BMWs, Land Rovers, etc.), and at our typical ambient temperatures of 15°C / 60°F to 30°C / 85°F, it can easily take 30 minutes or more with the engine running for the transmission fluid to reach 40°C / 104°F so the fluid level can be set. Even if we assume that with the vehicle moving the fluid warms up more quickly, this could still mean that the first 10 to 20 minutes of driving with fluid that is too viscous at 40°C / 104°F could be doing harm to the transmission. And under normal driving conditions, the transmission fluid is unlikely to ever reach 100°C / 212°F, so the KV100 may not be a relevant metric for choosing a transmission fluid.

Regarding oxidation and thermal stability, we have no way of knowing whether the anti-oxidant and viscosity-modifying additives, or any other additives in a non-approved fluid, will be as effective in a 6HP as those in Lifeguard 6, Mercon SP or Shell Spirax ATF MSP.

We second-guess the transmission engineers at our peril.

Cheers,

Don

 

x308 zf5hp24

 

The correct fluid at the time was LT71141, which is what I used years ago. Since then, ZF has released Lifeguard 5 as a retrospective equivalent to LT 71141. This is a rather specialised case where I would be happy to use whichever fluid was cheapest / readily available.

Richard

 

Hi Psycom,

This thread refers to the ZF 6HP24 six-speed transmissions. See the post at the link below for known-correct fluids for your five-speed ZF5HP24:

https://www.jaguarforums.com/forum/x...2/#post2776838

Cheers,

Don

 

Thank you so much!!! I'm in the process of building my "lift" that added 9 inches upfront. Stepping up the rear to match. THEN i can begin the process of breaking pan bolts?? 😱 hmm, Perhaps I should start on a list of things to have on hand before i make another move?

Any suggestions for my Christmas stocking stuffers? Bolts? Washers? Insurance? Drinks? Cheeeaders? Live streaming? Let's do it right!!

Seriously though, spare parts on hand can be returned. Beats needing and not finding!!!

Looks like i can send back the Royal Purple and get the Filly Beamstiener blitzen fittzen Again!! This time i won't cancel the order..Had it right the first time! Darn it.

Thank you and anyone else that pitches in on this never ending project.

Rich

 

Hmmmm,

When I had the fluid changed at the main dealer, they no longer used factory fluid, using BG exclusively. They claimed to have done thousands of fluid exchanges with no ill effect. Of course the data sample's meaningless. I never verified viscosity until now you bring it up. It's been about 8 years and about 2-3K miles of nearly all track driving since and I've not observed any issues. Hopefully it stays that way.

EDIT: BG LV 315 Viscosity, cSt @ 40°C (104°F) D445 28.5
Viscosity, cSt @ 100°C (212°F) D445 5.8

ZF LG 6 is 26.8 @ 40 and 5.6 @ 100, so not too much difference?

 

BG Low Viscosity Full Synthetic ATF, PN 315 was introduced in January of 2016, so hopefully that is what your dealership used, and not the higher-viscosity Premium Full Synthetic ATF. We still have no way of knowing whether the additives in the BG products meet the requirements established by the ZF and Shell engineers.

https://www.bgprod.com/blog/new-bg-l...d-performance/

It will be interesting to hear how your transmission holds up with more miles.

My cynical suspicion is that dealerships enter contracts to use the BG products because of the high profit margins and the fact that customers can't price-shop because BG products are not generally available directly to the public. Reviewing the Material Safety Data Sheets for BG products does not suggest there is anything advanced or superior about them.

Cheers,

Don

 

I recall at the time they claimed it met the specs for the Jag/LG6 fluid and I did see the spec sheet which indicated the LG6 equivalency so I reckon that's what they used, hopefully. The biggest benefit to the end user's the lifetime warranty added to the vehicle, which I have had the occasion to use on another vehicle.

 

Interesting, an actual Dealer used BG fluids?
Just this last year, ZF Lifeguard was used in 2 of my mine.