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We've all done something on our cars that we wish we hadn't!
Fluids known to be correct in your ZF 5HP24 transmission are:
ZF LifeGuard 5
ESSO LT 71141
Mobil 1 LT 71141
Febi Automatikgetriebeöl Nr. 29738
VW/Audi G 052 162 A2
Pentosin ATF 1
Ravenol ATF 4/5 HP
Of these, the ones I have found most easily and affordably in the U.S. are the Febi and the Pentosin. I order the Febi from ebay (partscontainer is a favorite seller), or I get the Pentosin from one of the local auto parts stores (they usually have to order it in but can typically get it within a day or two).
When you have the fluid and are ready to inject it into your transmission, important steps include:
1. You must have a method of measuring the transmission fluid temperature; the best is to use the transmission's temperature sensor and read its signal with a scan tool via Live Data; an alternate method is an infrared thermometer aimed at the fluid draining from the transmission, not at the pan (the pan temperature can vary greatly from that of the fluid);
2. The vehicle must be level;
3. The engine must be running;
4. Hold the brake and shift through each gear position, holding each one at least 3 seconds;
5. Do not open the transmission fill plug until the fluid temperature reaches 30ºC; if you are using an infrared thermometer, open the fill plug when its temp is a little lower than that;
6. Begin adding fluid until it just overflows;
7. When the fluid temperature reaches 40ºC and fluid is just trickling out of the fill hole, reinsert the fill plug and tighten;
8. If the fluid temperature reaches 50ºC, the fluid level will be too low, so reinstall the fill plug, allow the transmission to cool (it may take overnight to cool sufficiently), and start over;
IMPORTANT: Do not trust Valvoline, Castrol and other third-party fluidmakers who claim their fluid is "suitable" or "recommended" for your transmission. Exhaustive research by our forum members has established that these fluids do not conform to the chemical qualities of the known-correct fluids listed above.
Cheers,
Don
hello don. Do you know what the change is from this trans and multiple fluids to the 6hp26 using the shell only specs. Just curious what zf did and why
hello don. Do you know what the change is from this trans and multiple fluids to the 6hp26 using the shell only specs. Just curious what zf did and why
Hi Scott,
Apologies in advance to reddevil for getting a little off of his topic...
With the introduction of the 6HP26, ZF managed to fit six forward gears into a smaller package than the previous 5HP24 five-speed. The introductory technical documentation described the very fine tolerances required to produce this first 6-speed automatic transmission for passenger cars, and ZF introduced the new low-viscosity semi-synthetic fluid specifically for the 6HP, Lifeguard 6 / Shell M1375.4. This fluid is not backward-compatible for the 5HP or 4HP transmissions. The 6HP transmissions were initially marketed as "Sealed for Life," with no fluid or filter changes requred for the life of the vehicle. ZF subsequently revised their recommendation to "every 80,000 to 120,000 km, or every 8 years at the latest."
The kinematic viscosity at 40ºC of Lifeguard 5 / ESSO LT 71141 fluid is 37 mm2/s, which is a little thinner than the Dexron III used in the earlier 4-speed ZF transmissions (38-44 mm2/s). But the KV40 of Lifeguard 6 / Shell M1375.4 is just 26.8 mm2/s, significantly thinner than the previous fluids, presumably so it could better flow at all temperatures through the smaller passages in the more tightly-packaged 6HP.
The only other fluids we know to be equivalent to Lifeguard 6 are Ford Motorcraft Mercon SP and Shell Spirax S4 ATF MSP. LG6 and Spirax are manufactured by Royal Dutch Shell, and Mercon SP is manufactured by Shell U.S.A. (Ford licensed the 6HP from ZF for use in some of its vehicles).
As with Lifeguard 5, no Valvoline or Castrol fluids are known to be equivalent to Lifeguard 6, despite those companies' claims, which can be easily disproved.
Some forum members have indicated that Royal Purple Max full synthetic
is compatible. My Dad used Royal Purple all his life and swore by it.
Hi Randy,
If you will study the Material Safety Data Sheets for Royal Purple Max ATF and Lifeguard 5, you will see that while their kinematic viscosities are similar, their published ingredients are completely different. The Royal Purple appears to be (and is described by Royal Purple as) an equivalent to Dexron III and its many clones. Therefore, it might be fine in a ZF 4HP24. But there is no evidence to suggest that it would be correct in a ZF 5- or 6-speed transmission. It is significantly too viscous for the 6-speed transmissions.
Given that transmission fluid-related damage tends to occur over tens of thousands of miles, why would we risk using a fluid whose properties are different from those specified by ZF?
If you will study the Material Safety Data Sheets for Royal Purple Max ATF and Lifeguard 5, you will see that while their kinematic viscosities are similar, their published ingredients are completely different. The Royal Purple appears to be (and is described by Royal Purple as) an equivalent to Dexron III and its many clones. Therefore, it might be fine in a ZF 4HP24. But there is no evidence to suggest that it would be correct in a ZF 5- or 6-speed transmission. It is significantly too viscous for the 6-speed transmissions.
Given that transmission fluid-related damage tends to occur over tens of thousands of miles, why would we risk using a fluid whose properties are different from those specified by ZF?
If you will study the Material Safety Data Sheets for Royal Purple Max ATF and Lifeguard 5, you will see that while their kinematic viscosities are similar, their published ingredients are completely different. The Royal Purple appears to be (and is described by Royal Purple as) an equivalent to Dexron III and its many clones. Therefore, it might be fine in a ZF 4HP24. But there is no evidence to suggest that it would be correct in a ZF 5- or 6-speed transmission. It is significantly too viscous for the 6-speed transmissions.
Given that transmission fluid-related damage tends to occur over tens of thousands of miles, why would we risk using a fluid whose properties are different from those specified by ZF?
Thanks for that great information. I was tempted by the better price, but
something felt wrong. Surely others would have researched this and
discovered the disparity. I appreciate the catch.
You can make your life easier and just fill via cooler line (upper at the radiator)
Fill a bit more fluid then you have drained, wait till 30, open filler, let overflow and close
Saves you a lot of wiggling in tight space between hot exhaust pipes, which is a worst part of whole process.
Given it usually drains 4.5 i would put 5 l there
I just bought a 1998 XK8 with a failed ZF 5HP24 for cheap.
I have 3 XJ8 parts cars so I pulled a 1998 sedan trans and replaced the forward drum, 'just-because'.
The failed gearbox was rebuilt by some shop in Houston and lasted 18,000 miles.(this is the reason the car was for sale cheap)
Before removing the gearbox I thought I would check the fluid level.
The fluid was RED. (not a good sign)
There is no compatible 5HP24 fluid colored RED.
The lines and cooler in the radiator need flushing out.
I have the good-used gearbox ready to be installed in a few days.
I have a 3 bay shop with two lifts on my rural property. I quit the dealer in 2006 and been working out of here since then.
Still do jobs for old customers.
I dropped the powertrain complete because someone stripped the cataverter nuts on the manifold and I needed access to chisel them off to get to the bellhousing bolts.
New exhaust studs/nuts and back in business.
