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

Originally Posted by Matty_P

Had some issues with the gearbox since i purchased the D3. Its throwing up F on the dashboard and message similar to Transmission fault limited gears available.

Long story short - its booked in with Transmission Centre at Underwood. The owner Scott gave me 30 min of his time, checked for fault codes and found two saying slipping in 5th gear. He cleared the codes no charge gave me a 20 min lesson on the ZF box as well as showed me the differences between the current plastic pan and the metal version with filter. Awesome guy generous with his time considering i havent given him any money.

Interesting discussion about the Life Guard 6 oil ---- he doesnt use much of it, only if its a car under warranty. Cant remember the exact name of the oil he uses - its either "Regal" or "Regent". He does a lot a ZF boxes and said he uses the non LifeGuard oil for 95% of services / rebuilds. He said that LifeGuard 6 at the time had a patent around some of the additives that it used, this patent has since expired and the other oil providers have caught up. Im booked in Friday week for pan change and service, fingers crossed it fixes the problem - he said 50-60% chance it will given the limited amount of errors the box is producing.

Matt P

Over a week without flames for not using LG fluid? What is this forum becoming? Tombie has been quiet. I hope he’s ok?
I don’t use LG but use Motul ATF VI which is their claimed equivalent. I’ve been using it for four years in a trans with 200k km when I acquired and previously original fluid. So far so good. I change it annually dropping 5L and replacing so slowly diluting the original fluid. It’s now 253k km.

Penrite now have a LG6 equivalent trans fluid ‘ATF BMV’.

”ATF BMV may be used in ZF 6, 8 and 9 speed automatic transmissions where Lifeguard 6, 8 & 9 is recommended in vehicles”

ATF BMV (Full Syn) | Penrite Oil

Originally Posted by DiscoJeffster

Over a week without flames for not using LG fluid? What is this forum becoming? Tombie has been quiet. I hope he’s ok?
I don’t use LG but use Motul ATF VI which is their claimed equivalent. I’ve been using it for four years in a trans with 200k km when I acquired and previously original fluid. So far so good. I change it annually dropping 5L and replacing so slowly diluting the original fluid. It’s now 253k km.

Well Dr tranny and a mega flush didnt fix my issue so forked out $4500 and had the box reconditioned including TC and valve body. Been driving for a couple of days no issues, the tacho hunts a little bit in the 1000-1300 range but not too concerned at this stage as i guess the box needs to settle back in and relearn my driving habits.
Fuel economy has improved from a solid 10.4 ltrs/100 to 9.7-10.2ltrs/100.

Looking forward to getting off road now that i have some confidence in the box.

Matt P

Originally Posted by Matty_P

Well Dr tranny and a mega flush didnt fix my issue so forked out $4500 and had the box reconditioned including TC and valve body. Been driving for a couple of days no issues, the tacho hunts a little bit in the 1000-1300 range but not too concerned at this stage as i guess the box needs to settle back in and relearn my driving habits.
Fuel economy has improved from a solid 10.4 ltrs/100 to 9.7-10.2ltrs/100.

Looking forward to getting off road now that i have some confidence in the box.

Matt P

Pretty reasonable value.

Originally Posted by rar110

Pretty reasonable value.

Yep price was reasonable and I will get about $1700 back from the dealer on warranty....pitty i forked out for the mega flush.....that said i had the pan upgraded at the same time.

Gday...

Looking for advice ... probably more like reassurance.

Background:
Discovery 3 2.7TDV6 auto. Has 255,000Km on clock now. I bought in 2010 with 72,000Km.
I tow a 2,600Kg van - have probably done 100,000Km+ with the van on.
Auto fluid/filter flushed and changed at 80,000Km and steel pan fitted.
Fluid/filter changed at 150,000Km and Dr Tranny inserted, fluid/filter and flush and Dr Tranny at 200,000Km, fluid changed and Dr Tranny at 250,000Km.
Dr Tranny only used as 'insurance' as all gear changes have always been smooth and faultless.
Box has been perfect for the last 5,000Km since last fluid change except for today.
Yes, I am probably reacting too quickly.
Today, without the van attached, it makes a clunk changing from 1st to 2nd when taking off very slowly - slight throttle.
If I take off 'briskly' no clunk, but it is not as smooth (sort of slower change up) as the change from 2nd to 3rd and upward.
Changes down automatically through gears without problem - smoothly as always ... until I am about stopped and as I stop, there is a clunk as it changes back to 1st.
Other than that, I am very happy with the box and its changes.
I have never had a shudder or any other indication of anything untoward in the whole time I have enjoyed this great vehicle.
Any ideas from those who know much more than I?
Cheers - John

Mine’s similar age @ 254,000 km. Mine also has a slight clunk when going 2nd to 1st stopping. I’ve never let it bother me. It’s also a touch rougher when cold for 1st to 2nd and 3rd but smooths out when warm

In my view Dr Tranny is a band aid solution - I dont think I would have been using it in a good condition, well serviced gearbox. I am not sure what the long term implications of its use are. I am not a person who believes in additives in normal circumstances but I do accept that Dr Tranny in a gearbox/TC that is starting to play up is a good stop gap until the underlying condition can be dealt with.

As to your issue, sounds more gearbox rather than issues in the torque converter where Dr Tranny has the biggest positive impact - all I can assume some of the wear components in the gearbox are starting to play up and may need replacing but from the description I cannot suggest what it might be.

There have been threads in the past months of people rebuilding some bits themselves so maybe they will come along with some advice.

Good luck with it.

Garry