Discovery Transmission issues

[smark]

Hi all. My son has a 2001 Discovery II that has a shifting issue. Clearly not working properly. When I looked into it I discovered a lot of fluid that had leaked from what I think is the transfer case. I am not familiar with Land Rovers so done of the terminology is confusing. It has an automatic but I assume the transfer case uses a different oil. The fluid that had leaked is red which is typical ( I guess) for automatic transmissions. I don't really see anything leaking from the transmission.
Does the transmission share oil with the transfer case? If so that would explain the transmission problems due to low fluid.

 

[joey]

Transfer case uses gear oil I used 90/140 when I did mine last.

 

[joey]

Changing the transmission fluid on any car or truck is a vital part of preventative maintence.

Read your owners manual but it is generally recommended that you change the transmission fluid every 30,000 miles and the filter every 60,000 miles.

By doing this cheap preventative maintence you can help insure a long and healthy life for your transmission.

Land Rovers use Dexron III, try and buy a name brand like (Valvoline High Mileage ATF) 6 quarts on hand for this, 8 quarts for when you change the filter too.

You will need a 8mm allen wrench for the fill/check plug and a 5mm allen wrench for the drain plug.

The drain plug is on the bottom of the transmission oil sump and the fill/check plug is on the front of the transmission sump.

Remove the fill/check plug and then place your drain pan under the transmission sump and remove the drain plug.

Once all of the fluid has drained out clean the area around the drain plug and make sure that you clean the drain plug threads and that the washer is still in place.

Then using a hand pump such as this that you can buy at any store for around $10 US refill the transmission.

Pump the new transmission fluid into the fill/check hole until it starts to come out of the hole, replace the plug.

Start the truck and leave it running (make sure not to come into contact with the extremely hot catalytic converters). Then shift though all of the transmission gears and hold each one for 2-3 seconds, starting in park and continue until you reach 1st, then go back to park.

Reinstall the fill/check plug and make sure that the transmission is full, fluid should come out at a nice steady rate, if so you are full.

Pour your dirty transmission fluid into a container and take it to be recycled, any quick lube oil change place will take it as well as autoparts stores.

Budget one hour for this job.

 

[txfromwi]

Not sure about the 2001, as a general statement, the transfer case function can be both internal to or external to the transmission itself.
I can tell you that in my 2013-2016 LR4's the transfer case is separate and is external to the transmission proper.

First find the leak.
Remove all protective plates/shrouds and wipe everything down.
I use alcohol wipes or Clorox wipes.
Get it super clean then drive a bit, then- after it cools - look everywhere for leaks - keeping in mind that the transmission fluid in particular migrates along seals and ridges and can drip from locations far removed from the actual leak.

I am no transmission expert, but I have learned that rough shifting is most likely caused by the mechatronic seals failing, it's not too bad a job - IF you can get it apart - again your 2001 may be different than my vehicles.

If you have a transfer case leak, at the very least - top it up - on the 2013 the fill instructions for the TRANSFER CASE are to fill to the bottom of the fill plug. Of course best to drain and refill...
Instructions for the transmission are more involved - and, again, at least for the 2013-2016, involve filling the transmission when the fluid is at a specific temperature.

If you want some background info from my project on the 2013 transmission pan swap / flush and if you can stay awake....
See this:

 

[joey]

The 99.5 - 04 Discovery II has a separate transmission and transfer case.

 

[smark]

Thanks for all the info on transmission service. Hoping that fluid change will solve the issue.
I watched a couple of videos. Only remaining question is regarding fill/drain plugs. Are either of these plugs left hand thread? They seem tight and I don't want to strip the threads trying to get them out?

 

[Rover Range]

All threads are right hand.

 

[txfromwi]

Those are plastic pans and are designed as single use components.
It been a while so from memory, I believe that the pan for the 8 speed (2014-2016) has the filter as a built in and non replaceable component.
For the 6 speed, the filter is absolutely built into the pan.

As far as removing that plastic drain plug in the plastic pan I was not able to achieve that on the 8 speed, it's a plastic plug and my brand new fitting just slipped around and around because the plastic deformed to easily. So I need to drill a hole and drain it that way.
On the 6 speed, I was able to remove the plastic drain plug with no issues.

On both the torque is given on the plug itself.