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

My Disco 3 used to shudder and the rpm was up and down under the load.
I've been told that my tranny needs to be replaced with reconditioned one (min$5,500 to $12,000).
After reading a forum about Dr. Tranny in Disco3.com, I ordered 2 of them on ebay delivered to Sydney total cost of less than $30.
The result? - MAGIC, MIRACLE!
As soon as I added 2 tubes of Dr Tranny through the upper tranny cooling hose, all the shudder is gone!
It's been 3 weeks (2,000km) since I added Dr Tranny and no problem I have ever since.
If you have torque converter problem like shudder/judder, try with Dr Tranny first.

Hi all,

Well had the box flushed and filled at Graeme Coopers in Sydney, shudder GONE.

The tranny fluid that came out was disgusting, and the price was a third of the cost than the Land Rover dealer.

Graeme Ccooper recommend a tranny oil change every 40,000km will be doing that from now on.

Cheers

Dr Tranny looks like interesting stuff.

Dr. Tranny Instant Shudder Fixx

I have had terrible shudder ,were quoted I require new torque converter done a double flush with the OEM oil , still had a shudder.
I flushed again , filled with Fuchs ATF 4400 and added 2 x tubes of Dr Tranny, have NONE, NOTHING , ZERO shudder for the last 28 000km.
I tour in Southern Africa towing a trailer and tow boats on the beach , it is as smooth as new.

Dr Tranny WORKS!!!!!!!!!

I had my transmission serviced today @ 130000, last time at 88000. Same auto shop but this time they put GW syntrans in it. I should have asked first but i didnt because they used lifeguard 6 last time. The are well regarded. i queried them and he said they switched from lifeguard 6 about 9 months ago without issue. ATF was $108! I googled it and seems lots of the falcon guys are saying it is good. I have to say iam nervous. Box is very smooth though this time. I couldn't notice any change at the 88000 service. My box has not has any problems and I tow a 2.5T van. If If it does develop problems I will now wonder about the oil.

Not an issue if your service people are prepared to warrant your gearbox against failure.

For the price you paid for ATF I assume you only got a basic ATF change and not the full on change.

When looking at the GW website, I did not see Lifeguard 6 on the list of oils it could replace.

I certainly hope that the GW ATF proves to be Ok but at this stage it is a bit too early for me to switch.

Please let us know how you go.

Cheers

Garry

If your shop has put ATF in the box you may want to think about getting them to change it back to lg6 quickly. It may not cause issues immediately but they WILL develop and by the time they do it will be too late.

Penrite SIN ATF (now ATF FS) was specified by Penrite for this box, but check their website and they now say it is specifically not for use in ZF 6 and 8 speed boxes. Friction, lubrication, pressure and temperature characteristics of LG6 fluid is designed specially for the 6HPs!

Using ATF can causes issues with the valve operation, clutch operation and torque converter operation.

When I bought my car I did a full ATF oil change and used Penrite ATF FS as generally it is one of the highest spec ATFs on the market.

Luckily for me, my gearbox started acting up almost immediately and I only drove 150km on it. The issues included:

-increased noise and vibration (not shudder)
-shudder got WORSE
-grinding noise at 70 and 100km/h
-torque converter 'squawk' on gear changes (sounds like a squeaking noise)

Needless to say I went to the nearest Ford dealer and bought 8ltr of LG6 (at $60 per litre )

That fixed those issues apart from the shudder, which is now mostly gone after a megaflush and a tube of doc tranny

This is in no way an attack at Penrite, I believe their product is good, it's just not for this gearbox. I believe most LR specialists will tell you the exact same thing. I have spoken to a couple about it myself.

At the end of the day, keep your eyes and ears open for any change of operation in the box!

I spoke to Gulf Western today and they confirmed syntrans is suitable for ZF6. Apparently is states so on the label. He said it has been used without any problem in ZF6 for 2 years now. He said they would be worried about legal liability if it wasn't right. He said ZF will not certify anyone's ATF for their product but ZF have confirmed the oil contains the right additives. I can't find anything negative on the ford forums and it appears a number of tranny shops are now using it. After 300km the box is certainly behaving normally and the shifts are much smoother since the service. I am kicking myself for not specifying LG6 but iam feeling more confident. Keep ya all posted.