Thread: Disco 3/4 Automatic Transmission FAQ - 6 Speed

Am I correct in assuming that there's a couple of different steel pans for the auto trans? Mine defiantly no longer has a plastic trans pan, but the steel one that's on there has no drain plug? Am I correct in saying that the pan everyone's using has a drain plug in it?

The BMW version of the pan has a drain plug whereas the Ford version does not.

Thanks, that explains why mine has a BMW sticker on it

Regards
Tote

Just for reference, I bought a steel sump conversion kit direct from ZF yesterday, as well as a mechatronic plug seal. $271 for that - which included the BMW X5 steel sump with drain plug. I also got 6L of ZF Lifeguard Fluid 6 from Repco (using NRMA membership discount of 10%) for $189 - or $31.50 a litre.

I have been refused service at 2 auto transmission shops - as they know there are problems with these ZF (as previously mentioned by Graeme) and don't want to be a part of the "fun". I don't want a LR dealership to have their "technicians" perform the work - as I am sure this is way below their obvious skills (at $150/hr!).

Good luck to all with their autos!

So why does land rover fit the plastic sump, that is a bugger to service if BMW and ford fit a steel one?

I've read the thread and have arranged to get it serviced and new sump next month. my disco 3 has done 130K km and bought it last month,

LR don't care about auto servicing, they say that the auto is sealed for life. "Life" means after their warranty period expires, so they have no interest in making servicing easier as they don't want to have to service the auto at all. Also the plastic pan is harder to remove and therefore the end user can be charged more.

BTW, there MAY be a real reason for it, but the above is far more likely.

Originally Posted by Tote

Since my D3 has been getting the shudders I thought I'd post some of my research on a new thread rather than generating heaps of posts on the FAQ. Happy to be corrected on any points that other people know of, maybe we'll all learn something. So to kick it off....

Transmission is a ZF 6HP26 unit. Is currently fitted to BMWs, Ford Falcons and Territories, Audis and Jaguars to name a few

The transmission has been around in one form or another since 2001 when it was introduced on a 7 series

ZF have designated the transmission as "sealed for life" but a more accurate description of this strategy would be "sealed until the warranty period is over"

The Land Rover variant uses a plastic sump which has an inbuilt filter which is a throwaway with the sump at service time. The filter also means that the engine has to be lifted from one mount to fit the new sump. ZF make a steel sump part number 1068 103 820 01 Kit Sump. an alloy sump may also be available ex Ford. These variants do not have the filter inbuilt and can be fitted / removed without lifting the engine.

Fluid for these transmissions is ZF LifguardFluid6 part number S671 090 253 for a 20 litre drum. Dealers charge $78 a litre, other repairers less but it's still expensive.
Other alternatives may be Motospecs Part # 749626, Ford RI-28, Shell ATF M 1375.4, Mercon SP XT-6-QSP Ford have a RRP of $48 a litre for their oil.


The design of the 6hp26 is different in that it does not have bands but rather clutch packs and the transmission is completely electronically controlled. The torque converter clutch is modulated in that it can be engaging and releasing at a rapid rate to allow a transition between fully locked up and disengaged. The torque converter clutch can lock up in all gears

Due to these transmissions having no service schedule they develop a "shudder" that is similar to driving over a ripple strip embedded in the white line at the edge of a road. This is caused by the degredation of the oil and causes wear to the torque converter clutch and potentially damages the rest of the transmission through contamination and overheating.

It would seem that 50,000KM would be a good time to change the transmission fluid to delay the fault above happening.

Sport mode reduces the shudder substantially, possibly because the transmission is more likely to kick down a gear in response to increased load rather than modulating the torque converter to allow some slip.

There are reports from the UK of coolant contamination from the transmission cooler in the radiator becoming porous. It may be worthwhile to consider testing old fluid for glycol as a transmission flush will not help for long.

It's NOT a "Land Rover Problem".... Googling the transmission model number brings up lots of tales of woe from owners of these transmissions that have failed due to lack of oil changes.

When off road in steep country it is preferable to lock the vehicle in a suitable gear to reduce heat load on the transmission rather than leaving it in drive.

A new transmission will cost you in the vicinity of $7000 so regular oil changes make sense.

Thats all I can think of for now, any other thoughts welcome.
RMP, maybe when we have a complete list we could revise and put in the FAQ?

Regards,
Tote

Thanking you, I have just had our D4 auto trans oil done, old oil checked for status, and new sump pan and filter. 94 K Km Ian A

Hi All,

FYI- Rover Works Mitchell in the ACT did my transmission pan serice. Cost me $1250 for the modified steel pan with a drain plug, 8ltrs of fluid, labour and code clearance / resetting, including GST.

I recently picked up a 7/2011 Disco 4 TDV6 2.7 wth the 6 speed with 162000 kms. Whilst high kms at 47K pa, they were mainly highway miles (previous owners did a hwy commuite to and from work of approx 50km each way so thats 25K alone, and the balance of annaul kms would have alot of highway running in and out of town. Not a lot of towing - horse people apparently and a 2 horse float is approx 2.5 tonne, and horse people don't tend to tow long distances or fast in my experience). So, despite the kms, the transmission was fine. I had the preventative maintenance modification done anyway given the kms and as I tow.